ATI TEAS 7 Science Flashcards: A&P, Biology, Chemistry & Scientific Reasoning
Practice 446 original ATI TEAS 7 Science recall and mini-scenario cards across A&P, biology, chemistry, and scientific reasoning.
Apie šį rinkinį
Build the core Science knowledge and reasoning used for ATI TEAS 7 with 446 independently authored flashcards.
What this deck practices
- Structure or concept → function: body systems, cells, molecules, atoms, solutions, and experimental parts.
- Function, outcome, or evidence → concept: selective reverse recall when recognizing the name matters in practice.
- Cause or condition → effect: physiology, chemical changes, reaction conditions, inheritance, and experimental predictions.
- Process and order: circulation, ventilation, digestion, urine formation, gene expression, cell division, and scientific investigations.
- Application: short calculations, comparisons, data interpretations, and original mini-scenarios.
The deck does not mechanically reverse every fact. It excludes multiple-choice distractors, exhaustive anatomy lists, obscure chemical nomenclature, advanced pathophysiology, pharmacology, and nursing-school procedures because those mappings do not improve entry-level TEAS Science recall.
The sequence introduces prerequisites before dependent ideas: anatomical language before body systems, cells before genetics, atoms before reactions, and measurement before experimental design. Related forward and reverse variants are separated so one card does not immediately reveal another.
Coverage follows the four Science areas and relative emphasis in ATI's public ATI TEAS 7 content outline: Human Anatomy and Physiology, Biology, Chemistry, and Scientific Reasoning. The public outline defines scope only. Questions, answers, explanations, examples, and ordering were independently authored from common scientific knowledge checked against open educational and official public sources.
No exam question, mark scheme, paid ATI flashcard, test-bank item, or curriculum text was copied. This is an independent, unofficial educational deck by Flashcards Open Source App. ATI and TEAS are marks of Assessment Technologies Institute, L.L.C.; this deck is not affiliated with, endorsed by, or produced by ATI. See ATI's official exam details for current requirements.
Šio rinkinio kortelės
1 kortelė
Klausimas
What posture defines the standard anatomical position?
Atsakymas
Standing upright, facing forward, with arms at the sides and palms forward. The feet point forward, giving anatomy a consistent reference position.
2 kortelė
Klausimas
In anatomical language, what does superior mean?
Atsakymas
Toward the head or above another structure. Inferior means toward the feet or below.
3 kortelė
Klausimas
Which anatomical plane divides the body into left and right portions?
Atsakymas
The sagittal plane. A midsagittal plane divides the body into equal left and right halves.
4 kortelė
Klausimas
Why does the body use feedback mechanisms?
Atsakymas
To regulate internal conditions. Feedback compares a condition with a set range and triggers responses that adjust it.
5 kortelė
Klausimas
What is the order of structural organization from simplest to most complex?
Atsakymas
Chemical, cellular, tissue, organ, organ system, organism. Each level builds on interactions at the preceding level.
6 kortelė
Klausimas
What does anterior mean in human anatomy?
Atsakymas
Toward the front of the body. Posterior means toward the back.
7 kortelė
Klausimas
Which plane divides the body into upper and lower portions?
Atsakymas
The transverse plane. It is also called the horizontal plane.
8 kortelė
Klausimas
What is homeostasis?
Atsakymas
The maintenance of a relatively stable internal environment. It is dynamic rather than perfectly unchanging.
9 kortelė
Klausimas
Which major body cavity contains the brain and spinal cord?
Atsakymas
The dorsal body cavity. Its cranial cavity holds the brain, and its vertebral cavity holds the spinal cord.
10 kortelė
Klausimas
What does medial mean in anatomical language?
Atsakymas
Toward the body's midline. Lateral means farther from the midline.
11 kortelė
Klausimas
A rise in body temperature triggers sweating. What control pattern is this?
Atsakymas
Negative feedback. The response opposes the original temperature change and moves the body toward its normal range.
12 kortelė
Klausimas
Which anatomical plane divides the body into front and back portions?
Atsakymas
The frontal, or coronal, plane. It separates anterior from posterior portions.
13 kortelė
Klausimas
Which major body cavity contains the thoracic and abdominopelvic cavities?
Atsakymas
The ventral body cavity. The diaphragm separates its thoracic and abdominopelvic portions.
14 kortelė
Klausimas
What does proximal mean when describing a limb?
Atsakymas
Closer to the limb's point of attachment. Distal means farther from that point.
15 kortelė
Klausimas
How does positive feedback differ from negative feedback?
Atsakymas
Positive feedback amplifies the initial change. Negative feedback opposes a change; positive feedback continues until a stopping event occurs.
16 kortelė
Klausimas
Which tissue type covers surfaces and lines body cavities?
Atsakymas
Epithelial tissue. It also forms many glands and often serves protective, absorptive, or secretory roles.
17 kortelė
Klausimas
Which tissue type mainly supports, binds, and protects other tissues?
Atsakymas
Connective tissue. Its cells are typically separated by an extracellular matrix.
18 kortelė
Klausimas
What shared property lets muscle tissue produce movement?
Atsakymas
Contractility. Muscle cells shorten or develop tension in response to stimulation.
19 kortelė
Klausimas
Which tissue type rapidly communicates by electrical signals?
Atsakymas
Nervous tissue. Neurons transmit signals, while supporting cells help maintain their environment.
20 kortelė
Klausimas
Why are tightly packed epithelial cells well suited for barriers?
Atsakymas
They leave little space between cells. This continuous arrangement limits passage across a surface.
21 kortelė
Klausimas
What distinguishes connective tissue from epithelial tissue?
Atsakymas
Connective tissue usually has abundant extracellular matrix. Epithelial cells are more tightly packed.
22 kortelė
Klausimas
What are the four basic human tissue types?
Atsakymas
Epithelial, connective, muscle, and nervous tissue. Organs contain two or more tissue types working together.
23 kortelė
Klausimas
What makes a structure an organ rather than a tissue?
Atsakymas
An organ combines multiple tissue types for a specific function. A tissue is a group of similar cells and matrix performing related work.
24 kortelė
Klausimas
What are the skeletal system's main functions?
Atsakymas
Support, protection, movement, mineral storage, blood-cell production, and fat storage. Bones also provide levers for muscles.
25 kortelė
Klausimas
What belongs to the axial skeleton?
Atsakymas
The skull, vertebral column, and thoracic cage. These structures form the body's central axis.
26 kortelė
Klausimas
How do compact and spongy bone differ?
Atsakymas
Compact bone is dense; spongy bone has a lattice of trabeculae. Both are organized living bone tissue.
27 kortelė
Klausimas
What is a joint?
Atsakymas
A place where two or more bones meet. Joint structure determines how much movement is possible.
28 kortelė
Klausimas
Which bone cell builds new bone matrix?
Atsakymas
An osteoblast. Osteoclasts break down bone, while osteocytes maintain mature bone tissue.
29 kortelė
Klausimas
What belongs to the appendicular skeleton?
Atsakymas
The limbs plus the shoulder and pelvic girdles. It attaches the limbs to the axial skeleton.
30 kortelė
Klausimas
What is the main role of red bone marrow?
Atsakymas
Blood-cell production. This process is called hematopoiesis.
31 kortelė
Klausimas
Which joint class allows the greatest range of motion?
Atsakymas
A synovial joint. A fluid-filled joint cavity reduces friction between articulating surfaces.
32 kortelė
Klausimas
Which bone cell breaks down bone matrix?
Atsakymas
An osteoclast. Bone resorption helps remodeling and mineral balance.
33 kortelė
Klausimas
What does a ligament connect?
Atsakymas
Bone to bone. A tendon connects muscle to bone.
34 kortelė
Klausimas
What is the shaft of a long bone called?
Atsakymas
The diaphysis. The enlarged ends are the epiphyses.
35 kortelė
Klausimas
Why is bone important to blood-calcium balance?
Atsakymas
Bone stores calcium and can release or absorb it during remodeling. Hormones regulate this exchange.
36 kortelė
Klausimas
What is stored mainly in yellow bone marrow?
Atsakymas
Fat. It serves as an energy reserve.
37 kortelė
Klausimas
What does articular cartilage do at a synovial joint?
Atsakymas
It reduces friction and absorbs shock. It covers the ends of articulating bones.
38 kortelė
Klausimas
Why must a broken bone receive a blood supply during healing?
Atsakymas
Repairing cells need oxygen and nutrients. Restored blood vessels support fracture healing.
39 kortelė
Klausimas
What is bone remodeling?
Atsakymas
Continuous removal and replacement of bone tissue. It repairs microdamage and helps bones adapt to stress.
40 kortelė
Klausimas
Which muscle tissue is usually under voluntary control?
Atsakymas
Skeletal muscle. Most skeletal muscles move the skeleton, while some, such as facial muscles, insert into skin or other soft tissue.
41 kortelė
Klausimas
What is a sarcomere?
Atsakymas
The basic contractile unit of striated muscle. It lies between two Z discs.
42 kortelė
Klausimas
What does a tendon connect?
Atsakymas
Muscle to bone. It transmits muscle force to the skeleton.
43 kortelė
Klausimas
Which proteins slide past one another during muscle contraction?
Atsakymas
Actin and myosin. Their interaction shortens sarcomeres without shortening the filaments themselves.
44 kortelė
Klausimas
Where is smooth muscle commonly found?
Atsakymas
In the walls of hollow organs and blood vessels. Its contractions are generally involuntary.
45 kortelė
Klausimas
What ion exposes binding sites needed for skeletal muscle contraction?
Atsakymas
Calcium. Its release inside the muscle fiber allows actin and myosin interaction.
46 kortelė
Klausimas
How do antagonistic muscle pairs move a joint?
Atsakymas
One muscle contracts while the opposing muscle relaxes. Reversing their roles moves the joint in the opposite direction.
47 kortelė
Klausimas
Why does muscle contraction require ATP?
Atsakymas
ATP powers cross-bridge cycling and ion pumps. It is also needed for myosin to detach from actin.
48 kortelė
Klausimas
Which muscle tissue makes up the heart wall?
Atsakymas
Cardiac muscle. It is striated, involuntary, and connected for coordinated pumping.
49 kortelė
Klausimas
During a typical muscle contraction, which attachment moves more: origin or insertion?
Atsakymas
The insertion. The origin is generally the more fixed attachment.
50 kortelė
Klausimas
Which type of neuron sends the signal that initiates skeletal-muscle contraction?
Atsakymas
A somatic motor neuron. It releases acetylcholine at the neuromuscular junction, triggering an action potential in the muscle fiber.
51 kortelė
Klausimas
What is muscle tone?
Atsakymas
Continuous low-level muscle tension. It helps maintain posture and readiness without producing a large movement.
52 kortelė
Klausimas
How does skeletal muscle help regulate body temperature?
Atsakymas
Contraction releases heat. Shivering increases rapid contractions when the body is cold.
53 kortelė
Klausimas
What are the three muscle tissue types?
Atsakymas
Skeletal, cardiac, and smooth muscle. They differ in location, structure, and control.
54 kortelė
Klausimas
What is a neuron's main function?
Atsakymas
To receive, process, and transmit information. Neurons use electrical signals and chemical messengers.
55 kortelė
Klausimas
What structures make up the central nervous system?
Atsakymas
The brain and spinal cord. They integrate information and coordinate responses.
56 kortelė
Klausimas
Which part of a neuron usually receives incoming signals?
Atsakymas
The dendrites. The cell body integrates much of that input.
57 kortelė
Klausimas
What does the peripheral nervous system include?
Atsakymas
Nerves and ganglia outside the brain and spinal cord. It links the central nervous system with the rest of the body.
58 kortelė
Klausimas
Which neuron structure carries an impulse away from the cell body?
Atsakymas
The axon. Its terminals communicate with another cell.
59 kortelė
Klausimas
Which nervous-system division controls skeletal muscles voluntarily?
Atsakymas
The somatic nervous system. It also carries sensory information from skin, muscles, and joints.
60 kortelė
Klausimas
What is a synapse?
Atsakymas
A junction where one neuron communicates with another cell. Chemical synapses use neurotransmitters across a small gap.
61 kortelė
Klausimas
Which nervous-system division regulates organs and glands without conscious control?
Atsakymas
The autonomic nervous system. It includes sympathetic and parasympathetic divisions.
62 kortelė
Klausimas
How does myelin affect nerve signaling?
Atsakymas
It speeds impulse conduction along an axon. Myelin insulates segments of the axon.
63 kortelė
Klausimas
Which autonomic division prepares the body for acute activity?
Atsakymas
The sympathetic division. It generally increases alertness and supports a fight-or-flight response.
64 kortelė
Klausimas
What is a reflex?
Atsakymas
A rapid, predictable response to a stimulus. A reflex pathway can act before conscious awareness.
65 kortelė
Klausimas
Which autonomic division supports rest, digestion, and energy conservation?
Atsakymas
The parasympathetic division. It generally promotes routine maintenance functions.
66 kortelė
Klausimas
Which brain region is most associated with conscious thought and voluntary movement?
Atsakymas
The cerebrum. Its cortex also processes much sensory information.
67 kortelė
Klausimas
Which brain region fine-tunes balance and coordinated movement?
Atsakymas
The cerebellum. It compares intended movement with sensory feedback.
68 kortelė
Klausimas
Which brain region controls vital automatic functions such as breathing and heart rate?
Atsakymas
The brainstem. It also connects higher brain regions with the spinal cord.
69 kortelė
Klausimas
How do sensory and motor neurons differ?
Atsakymas
Sensory neurons carry information toward the CNS; motor neurons carry commands away. Interneurons connect and process signals within the CNS.
70 kortelė
Klausimas
What does a sensory receptor do?
Atsakymas
It converts a stimulus into a neural signal. Different receptors respond best to particular forms of energy or chemicals.
71 kortelė
Klausimas
What is a hormone?
Atsakymas
A chemical messenger released into body fluids to affect target cells. A target responds only if it has the appropriate receptor.
72 kortelė
Klausimas
Why is the pituitary gland often called a master gland?
Atsakymas
Several pituitary hormones regulate other endocrine glands. The hypothalamus controls much of pituitary activity.
73 kortelė
Klausimas
Why can one hormone affect some cells but not others?
Atsakymas
Only target cells have the matching receptor. Receptor binding starts the cell's response.
74 kortelė
Klausimas
Which gland produces hormones that broadly increase metabolic activity?
Atsakymas
The thyroid gland. Thyroid hormones influence energy use and development.
75 kortelė
Klausimas
What is insulin's main effect on blood glucose?
Atsakymas
It lowers blood glucose. Insulin promotes glucose uptake and storage after a meal.
76 kortelė
Klausimas
Which glands release a hormone that raises blood calcium?
Atsakymas
The parathyroid glands. Parathyroid hormone acts on bone, kidneys, and vitamin D pathways.
77 kortelė
Klausimas
Which adrenal region releases epinephrine during acute stress?
Atsakymas
The adrenal medulla. Its hormones reinforce sympathetic nervous-system effects.
78 kortelė
Klausimas
Which organ has both endocrine and digestive functions?
Atsakymas
The pancreas. Its islets release hormones, while other cells release digestive enzymes.
79 kortelė
Klausimas
What is glucagon's main effect on blood glucose?
Atsakymas
It raises blood glucose. It promotes release of stored glucose during fasting.
80 kortelė
Klausimas
Rising thyroid hormone reduces its own upstream stimulation. What pattern is this?
Atsakymas
Negative feedback. The final hormone limits further release along the control pathway.
81 kortelė
Klausimas
Which adrenal region produces steroid hormones such as cortisol and aldosterone?
Atsakymas
The adrenal cortex. It surrounds the adrenal medulla.
82 kortelė
Klausimas
Which gland releases melatonin and helps regulate daily sleep timing?
Atsakymas
The pineal gland. Light information influences its secretion pattern.
83 kortelė
Klausimas
Which hormone directly increases collecting-duct water permeability?
Atsakymas
Antidiuretic hormone, or ADH. It makes collecting ducts more permeable to water, increasing water reabsorption and usually producing less, more concentrated urine.
84 kortelė
Klausimas
Which hormone strengthens uterine contractions during labor?
Atsakymas
Oxytocin. This is a classic positive-feedback pathway that ends after delivery.
85 kortelė
Klausimas
How does endocrine signaling generally differ from nervous signaling?
Atsakymas
It is usually slower to start and longer lasting. Hormones travel through body fluids, while neurons signal specific targets rapidly.
86 kortelė
Klausimas
What is plasma?
Atsakymas
The liquid portion of blood. It carries cells, nutrients, hormones, proteins, wastes, and dissolved gases.
87 kortelė
Klausimas
Which side of the heart pumps blood to the lungs?
Atsakymas
The right side. The right ventricle sends deoxygenated blood through the pulmonary trunk and arteries.
88 kortelė
Klausimas
What is the main function of red blood cells?
Atsakymas
Transporting oxygen. Their hemoglobin also carries a smaller share of carbon dioxide.
89 kortelė
Klausimas
What defines an artery?
Atsakymas
It carries blood away from the heart. Oxygen content does not define it; pulmonary arteries carry deoxygenated blood.
90 kortelė
Klausimas
What is the main function of white blood cells?
Atsakymas
Body defense. Different white blood cells recognize, attack, or coordinate responses to threats.
91 kortelė
Klausimas
Which side of the heart pumps blood into systemic circulation?
Atsakymas
The left side. The left ventricle sends oxygenated blood into the aorta.
92 kortelė
Klausimas
What is the main purpose of heart valves?
Atsakymas
To keep blood moving in one direction. Pressure differences open and close them.
93 kortelė
Klausimas
What defines a vein?
Atsakymas
It carries blood toward the heart. Many veins contain valves that limit backflow.
94 kortelė
Klausimas
What is the main role of platelets?
Atsakymas
Helping stop bleeding. They form a platelet plug and support clotting reactions at a damaged vessel.
95 kortelė
Klausimas
Why are capillaries well suited for exchange?
Atsakymas
Their walls are only one cell layer thick. Their small diameter and large total surface area support diffusion and filtration.
96 kortelė
Klausimas
After blood enters the right atrium, what chamber receives it next?
Atsakymas
The right ventricle. Blood passes through the tricuspid valve before entering that chamber.
97 kortelė
Klausimas
What happens during ventricular systole?
Atsakymas
The ventricles contract and eject blood. The right ventricle pumps to the lungs, and the left pumps to the body.
98 kortelė
Klausimas
What is pulmonary circulation?
Atsakymas
Blood flow between the heart and lungs. It allows gas exchange and returns oxygenated blood to the left atrium.
99 kortelė
Klausimas
What normally sets the heart's rhythm?
Atsakymas
The sinoatrial, or SA, node. Its spontaneous electrical activity initiates each heartbeat.
100 kortelė
Klausimas
What molecule in red blood cells binds oxygen?
Atsakymas
Hemoglobin. Its iron-containing heme groups bind oxygen reversibly.
101 kortelė
Klausimas
What happens during ventricular diastole?
Atsakymas
The ventricles relax and fill. Atrioventricular valves are open during most ventricular filling.
102 kortelė
Klausimas
What is systemic circulation?
Atsakymas
Blood flow between the heart and the body's tissues. It delivers oxygen and nutrients and returns wastes.
103 kortelė
Klausimas
What does arterial blood pressure measure?
Atsakymas
The force of blood against artery walls. It is commonly reported as systolic over diastolic pressure.
104 kortelė
Klausimas
What do coronary arteries supply?
Atsakymas
The heart muscle itself. Blocked coronary blood flow can deprive myocardium of oxygen.
105 kortelė
Klausimas
Which major vessels return systemic blood to the right atrium?
Atsakymas
The superior and inferior venae cavae. The superior vessel drains the upper body; the inferior drains the lower body.
106 kortelė
Klausimas
What is the respiratory system's primary gas-exchange function?
Atsakymas
Bringing oxygen into the body and removing carbon dioxide. Ventilation moves air, while diffusion exchanges gases.
107 kortelė
Klausimas
What is the airflow sequence from the pharynx to the gas-exchange surfaces?
Atsakymas
Pharynx, larynx, trachea, bronchi, bronchioles, alveoli. Each branch conducts air deeper into the lungs.
108 kortelė
Klausimas
Where does most gas exchange occur in the lungs?
Atsakymas
Across the alveolar-capillary membrane. Thin walls and a large surface area shorten diffusion distance.
109 kortelė
Klausimas
What does the diaphragm do during quiet inhalation?
Atsakymas
It contracts and moves downward. Thoracic volume rises, lung pressure falls, and air flows inward.
110 kortelė
Klausimas
Why does oxygen move from alveoli into pulmonary capillaries?
Atsakymas
Its partial pressure is higher in alveolar air than in incoming blood. Oxygen diffuses down that gradient.
111 kortelė
Klausimas
What drives quiet exhalation?
Atsakymas
Elastic recoil after inspiratory muscles relax. Thoracic volume falls and pressure pushes air outward.
112 kortelė
Klausimas
What is the pleura?
Atsakymas
A double membrane surrounding each lung. A thin fluid layer reduces friction during breathing.
113 kortelė
Klausimas
How is most oxygen transported in blood?
Atsakymas
Bound to hemoglobin in red blood cells. Only a small amount dissolves directly in plasma.
114 kortelė
Klausimas
Why does carbon dioxide move from pulmonary blood into alveoli?
Atsakymas
Its partial pressure is higher in incoming blood than in alveolar air. It diffuses down that gradient for exhalation.
115 kortelė
Klausimas
What helps keep swallowed material out of the airway?
Atsakymas
The epiglottis and coordinated swallowing reflexes. The laryngeal opening is protected as food passes.
116 kortelė
Klausimas
How does the conducting airway remove trapped particles?
Atsakymas
Mucus traps them, and cilia move the mucus toward the throat. This is the mucociliary escalator.
117 kortelė
Klausimas
In what form is most carbon dioxide transported in blood?
Atsakymas
As bicarbonate ions. Red blood cells help convert carbon dioxide and water into bicarbonate.
118 kortelė
Klausimas
Which blood change is a strong normal stimulus to increase breathing?
Atsakymas
A rise in carbon dioxide and the associated fall in pH. Brainstem centers adjust ventilation in response.
119 kortelė
Klausimas
Why must alveoli receive both air and blood?
Atsakymas
Gas exchange needs ventilation and perfusion. Air without blood flow, or blood without airflow, cannot exchange gases effectively.
120 kortelė
Klausimas
Why does ventilation increase during exercise?
Atsakymas
Active tissues use more oxygen and produce more carbon dioxide. Faster, deeper breathing helps meet that demand.
121 kortelė
Klausimas
What are the digestive system's core functions?
Atsakymas
Ingestion, digestion, absorption, and elimination. Movement and secretion support those processes.
122 kortelė
Klausimas
What is the alimentary-canal sequence after the mouth?
Atsakymas
Pharynx, esophagus, stomach, small intestine, large intestine, rectum, anus. Food passes through this continuous tube.
123 kortelė
Klausimas
What is mechanical digestion?
Atsakymas
Physical breakdown and mixing of food without changing its molecules. Chewing and stomach churning are examples.
124 kortelė
Klausimas
What are two major functions of the stomach?
Atsakymas
It stores and mixes food and begins substantial protein digestion. Acid denatures proteins, converts pepsinogen to pepsin, and provides the low pH pepsin needs.
125 kortelė
Klausimas
Where does most nutrient absorption occur?
Atsakymas
The small intestine. Folds, villi, and microvilli create a large absorptive surface.
126 kortelė
Klausimas
Which nutrient does salivary amylase begin digesting in the mouth?
Atsakymas
Carbohydrates, especially starch. Salivary amylase breaks starch into smaller carbohydrates.
127 kortelė
Klausimas
What is chemical digestion?
Atsakymas
Enzymatic breakdown of large food molecules into absorbable units. Chemical bonds are changed during the process.
128 kortelė
Klausimas
What is peristalsis?
Atsakymas
Wave-like smooth-muscle contractions that move material forward. It occurs throughout much of the digestive tract.
129 kortelė
Klausimas
What is a main function of the large intestine?
Atsakymas
Absorbing water and electrolytes and forming feces. Resident microbes also process some undigested material.
130 kortelė
Klausimas
What digestive product does the liver make?
Atsakymas
Bile. Bile salts help disperse dietary fat into smaller droplets.
131 kortelė
Klausimas
What does a digestive sphincter do?
Atsakymas
It regulates movement between regions of the digestive tract. Circular muscle contracts to close a passage.
132 kortelė
Klausimas
What does the pancreas release into the small intestine?
Atsakymas
Digestive enzymes and bicarbonate-rich fluid. Bicarbonate helps neutralize acidic material from the stomach.
133 kortelė
Klausimas
How do intestinal villi improve absorption?
Atsakymas
They increase surface area. Each villus contains blood capillaries and a lymphatic lacteal for transported nutrients.
134 kortelė
Klausimas
What is the gallbladder's role?
Atsakymas
It stores and concentrates bile. It releases bile into the small intestine when fatty food arrives.
135 kortelė
Klausimas
Which macronutrient's absorbed products usually enter intestinal lacteals before reaching the blood?
Atsakymas
Most dietary lipids. Their absorbed products travel through lymph before entering the bloodstream.
136 kortelė
Klausimas
Which accessory organs help digestion without food passing through them?
Atsakymas
The teeth, tongue, salivary glands, liver, gallbladder, and pancreas. Teeth and the tongue act mechanically; the other accessory organs add or store digestive secretions.
137 kortelė
Klausimas
What organs make up the urinary system?
Atsakymas
The kidneys, ureters, urinary bladder, and urethra. Kidneys make urine; the remaining organs transport, store, and release it.
138 kortelė
Klausimas
What is a nephron?
Atsakymas
The kidney's functional unit. It filters blood and adjusts the filtrate to form urine.
139 kortelė
Klausimas
Where does blood filtration begin in a nephron?
Atsakymas
At the renal corpuscle. Pressure pushes water and small solutes from glomerular capillaries into the capsule.
140 kortelė
Klausimas
What moves urine from a kidney to the bladder?
Atsakymas
A ureter. Smooth-muscle contractions propel urine along the tube.
141 kortelė
Klausimas
What is the urinary bladder's main role?
Atsakymas
Temporary urine storage. Stretch receptors help trigger the urge to urinate as it fills.
142 kortelė
Klausimas
Which structure carries urine from the bladder out of the body?
Atsakymas
The urethra. It is distinct from the ureters that enter the bladder.
143 kortelė
Klausimas
What is tubular reabsorption?
Atsakymas
Movement of useful substances from nephron fluid back into blood. Water, glucose, and ions are common examples.
144 kortelė
Klausimas
What is the glomerulus?
Atsakymas
A capillary tuft that filters blood in the renal corpuscle. Cells and most large proteins normally remain in circulation.
145 kortelė
Klausimas
How does more ADH change urine?
Atsakymas
It makes urine more concentrated and lowers its volume. More water is reabsorbed from the collecting ducts.
146 kortelė
Klausimas
What path does filtrate follow after entering the glomerular capsule?
Atsakymas
Proximal convoluted tubule → nephron loop → distal convoluted tubule → collecting duct. The collecting duct receives forming urine from multiple nephrons.
147 kortelė
Klausimas
What is tubular secretion?
Atsakymas
Movement of selected substances from blood into nephron fluid. It helps eliminate wastes and regulate ions and pH.
148 kortelė
Klausimas
Besides removing waste, what does the urinary system regulate?
Atsakymas
Water, electrolytes, acid-base balance, and blood volume. Kidney hormones also affect blood pressure and red-cell production.
149 kortelė
Klausimas
Why does dehydration usually reduce urine volume?
Atsakymas
The body conserves water by increasing renal reabsorption. ADH is an important signal in this response.
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Klausimas
Why do the kidneys receive a large blood flow?
Atsakymas
They must continuously filter plasma and regulate its composition. High flow supports waste removal and homeostasis.
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Klausimas
What is lymph?
Atsakymas
Interstitial fluid that has entered lymphatic vessels. It eventually returns to the bloodstream.
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Klausimas
What is innate immunity?
Atsakymas
Rapid, nonspecific defense present before a particular exposure. Barriers, inflammation, and several immune cells contribute.
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Klausimas
What is a major function of lymph nodes?
Atsakymas
Filtering lymph and providing sites for immune-cell activation. Swelling can reflect an active immune response.
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What does the spleen filter?
Atsakymas
Blood. It removes aged blood cells and supports immune responses to blood-borne antigens.
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Klausimas
What is a key function of B lymphocytes?
Atsakymas
Producing antibody-secreting cells and memory cells. Antibodies bind specific antigens.
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Klausimas
What distinguishes adaptive immunity?
Atsakymas
It targets specific antigens and develops memory. Later exposure can trigger a faster, stronger response.
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Klausimas
Which lymphatic organ is important for T-cell maturation?
Atsakymas
The thymus. It is most active early in life.
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Klausimas
What is the body's first physical barrier against many pathogens?
Atsakymas
Intact skin and mucous membranes. Their secretions and normal microbes add protection.
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What is a key function of T lymphocytes?
Atsakymas
Coordinating immune responses or killing infected cells. Different T-cell types perform different roles.
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Klausimas
What does an antibody bind?
Atsakymas
A specific antigen. Binding can neutralize a target or mark it for other immune defenses.
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Klausimas
What is the purpose of inflammation after tissue injury?
Atsakymas
To contain damage, recruit defenses, and begin repair. Redness, heat, swelling, and pain can accompany it.
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Klausimas
Why is a second adaptive response often faster than the first?
Atsakymas
Memory lymphocytes remain after the first exposure. They respond quickly when the same antigen appears again.
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Klausimas
What does a phagocyte do?
Atsakymas
It engulfs particles, microbes, or debris. Neutrophils and macrophages are important examples.
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Klausimas
How does vaccination support adaptive immunity?
Atsakymas
It safely exposes the immune system to antigen information. This promotes memory without requiring the full disease.
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Klausimas
Why is lymphatic fluid return important?
Atsakymas
It prevents excess interstitial fluid from accumulating. Lymphatic vessels return fluid and leaked proteins to blood.
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Klausimas
What structures belong to the integumentary system?
Atsakymas
Skin, hair, nails, sweat glands, and sebaceous glands. Together they form the body's outer covering.
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Klausimas
What is the epidermis?
Atsakymas
The outer epithelial layer of skin. It is avascular and contains protective keratinized cells.
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Klausimas
How does sweating cool the body?
Atsakymas
Evaporation removes heat from the skin. Skin blood-flow changes also help regulate heat loss.
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Klausimas
What is a major role of melanin in skin?
Atsakymas
Absorbing some ultraviolet radiation. It also contributes to skin and hair color.
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Klausimas
How does skin contribute to sensation?
Atsakymas
Sensory receptors detect touch, pressure, pain, and temperature. Nerves carry that information to the CNS.
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What is the dermis?
Atsakymas
The connective-tissue layer beneath the epidermis. It contains vessels, nerves, glands, and hair follicles.
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Klausimas
How does skin support vitamin D production?
Atsakymas
Ultraviolet light starts conversion of a skin molecule into a vitamin D precursor. The liver and kidneys complete activation.
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Klausimas
Why does a deep skin wound bleed but a shallow epidermal scrape may not?
Atsakymas
Blood vessels are in the dermis, not the epidermis. A wound must reach vascular tissue to damage them.
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Klausimas
What is a gamete?
Atsakymas
A haploid reproductive cell. Human sperm and oocytes each carry 23 chromosomes.
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Klausimas
What are the testes' two main reproductive functions?
Atsakymas
Producing sperm and secreting testosterone. Sperm develop in seminiferous tubules.
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Klausimas
What tube carries sperm from the epididymis toward the ejaculatory duct?
Atsakymas
The ductus, or vas, deferens. Smooth muscle propels sperm during ejaculation.
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Klausimas
What is ovulation?
Atsakymas
Release of a secondary oocyte from an ovary. A surge in luteinizing hormone helps trigger it.
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Klausimas
Where does fertilization usually occur?
Atsakymas
In a uterine tube. The early embryo then travels toward the uterus.
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Klausimas
What are the ovaries' two main reproductive functions?
Atsakymas
Producing oocytes and secreting sex hormones. Estrogen and progesterone help regulate the reproductive cycle.
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Klausimas
What is the uterus' main reproductive role?
Atsakymas
Supporting implantation and development of an embryo and fetus. Its muscular wall also contracts during birth.
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Klausimas
What causes menstruation when pregnancy does not occur?
Atsakymas
Falling ovarian hormones allow the uterine lining to shed. A new cycle then begins.
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Klausimas
How does a sperm cell's structure support its function?
Atsakymas
Its flagellum provides movement, and its head carries DNA plus enzymes used during fertilization. Mitochondria supply energy in the midpiece.
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Klausimas
What is the placenta's exchange role?
Atsakymas
It allows gases, nutrients, and wastes to move between maternal and fetal circulations. Their blood normally does not mix directly.
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Klausimas
Why is meiosis necessary for sexual reproduction?
Atsakymas
It halves chromosome number in gametes. Fertilization then restores the diploid number.
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Klausimas
How do sex hormones regulate reproductive control pathways?
Atsakymas
They usually feed back on the hypothalamus and pituitary. This adjusts release of hormones that act on the gonads.
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Klausimas
What does cell theory state?
Atsakymas
Living things are made of cells, cells are the basic units of life, and cells come from existing cells. These ideas link organism structure with cell division.
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Klausimas
What is the defining structural feature of a prokaryotic cell?
Atsakymas
It lacks a membrane-bound nucleus. Its DNA occupies a nucleoid region.
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Klausimas
What is the cell membrane's main role?
Atsakymas
Regulating movement between the cell and its environment. Its phospholipid bilayer is selectively permeable.
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Klausimas
What is the nucleus' main role?
Atsakymas
Storing most of a eukaryotic cell's DNA. Nuclear pores regulate exchange with the cytoplasm.
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Klausimas
Where are proteins assembled?
Atsakymas
At ribosomes. Ribosomes may float in cytosol or attach to rough endoplasmic reticulum.
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Klausimas
What distinguishes a eukaryotic cell from a prokaryotic cell?
Atsakymas
A eukaryotic cell has a membrane-bound nucleus and other membrane-bound organelles. Animals, plants, fungi, and protists are eukaryotes.
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Klausimas
What is a mitochondrion's main function?
Atsakymas
Producing most cellular ATP through aerobic respiration. Its inner membrane provides a large reaction surface.
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Klausimas
What does rough endoplasmic reticulum mainly produce?
Atsakymas
Proteins for secretion, membranes, or organelles. Ribosomes on its surface make the proteins.
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Klausimas
Which organelle carries out photosynthesis in plants and algae?
Atsakymas
The chloroplast. It converts light energy into chemical energy stored in organic molecules.
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Klausimas
What does the Golgi apparatus do?
Atsakymas
It modifies, sorts, and packages cell products. Vesicles carry those products to their destinations.
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Klausimas
What is a lysosome's role?
Atsakymas
Digesting worn cell parts and engulfed material. Its enzymes work best in an acidic interior.
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Klausimas
What are major functions of smooth endoplasmic reticulum?
Atsakymas
Lipid synthesis, detoxification, and calcium storage. Its membrane lacks attached ribosomes.
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Klausimas
What does the cytoskeleton provide?
Atsakymas
Cell shape, internal organization, movement, and transport tracks. It is built from protein filaments.
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Klausimas
What is diffusion?
Atsakymas
Net movement from higher to lower concentration. It is passive and continues until dynamic equilibrium is reached.
200 kortelė
Klausimas
What happens to an animal cell in a strongly hypotonic solution?
Atsakymas
Water enters and the cell swells. Without a cell wall, it may burst.
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Klausimas
What happens during interphase?
Atsakymas
The cell grows, performs normal functions, and copies its DNA. Interphase precedes mitotic division.
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Klausimas
What is the result of mitosis followed by cytokinesis?
Atsakymas
Two genetically similar daughter cells. Chromosome number is normally preserved.
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Klausimas
What is osmosis?
Atsakymas
Diffusion of water across a selectively permeable membrane. Water moves toward the side with more nonpenetrating solute.
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Klausimas
What happens to an animal cell in a hypertonic solution?
Atsakymas
Water leaves and the cell shrinks. The external solution has a higher effective solute concentration.
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Klausimas
Why are cells generally small?
Atsakymas
A high surface-area-to-volume ratio supports efficient exchange. Volume grows faster than surface area as a cell enlarges.
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Klausimas
What is cytokinesis?
Atsakymas
Division of the cytoplasm. It separates one cell into two after nuclear division.
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Klausimas
How does active transport differ from passive transport?
Atsakymas
It uses energy to move substances against a gradient. Passive transport moves down a gradient without direct energy input.
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Klausimas
What happens to an animal cell in an isotonic solution?
Atsakymas
There is no net water movement. Water still crosses in both directions at equal rates.
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Klausimas
Which structures are typical of plant cells but not animal cells?
Atsakymas
A cellulose cell wall, chloroplasts, and a large central vacuole. Both cell types have membranes, nuclei, and mitochondria.
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Klausimas
How do cells contribute to a multicellular organism's organization?
Atsakymas
Specialized cells form tissues, tissues form organs, and organs form systems. Division of labor supports complex functions.
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Klausimas
What is DNA's primary biological role?
Atsakymas
Storing hereditary information. Its nucleotide sequence contains instructions used to build functional RNA and proteins.
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Klausimas
What are the three parts of a DNA nucleotide?
Atsakymas
A deoxyribose sugar, a phosphate group, and a nitrogenous base. Nucleotides link to form each strand.
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Klausimas
Which bases pair in double-stranded DNA?
Atsakymas
Adenine with thymine, and cytosine with guanine. Hydrogen bonds hold complementary strands together.
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Klausimas
How does RNA differ from DNA?
Atsakymas
RNA usually has ribose, uses uracil instead of thymine, and is usually single-stranded. Several RNA types help express genes.
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Klausimas
What is a gene?
Atsakymas
A DNA sequence that contributes to a functional product. The product may be a protein or a functional RNA.
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Klausimas
What is a chromosome?
Atsakymas
A long DNA molecule packaged with proteins. It contains many genes and other sequences.
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Klausimas
What is DNA replication?
Atsakymas
Copying DNA before cell division. Each new DNA molecule contains one old strand and one newly made strand.
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Klausimas
What is the usual flow of information from a protein-coding gene?
Atsakymas
DNA to RNA to protein. Transcription makes RNA; translation builds the polypeptide.
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Klausimas
What happens during transcription?
Atsakymas
RNA is synthesized from a DNA template. For a protein-coding gene, that RNA functions as or is processed into messenger RNA.
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Klausimas
What does messenger RNA carry?
Atsakymas
A copy of coding information from DNA to a ribosome. Its codons specify the amino-acid sequence.
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Klausimas
What is a codon?
Atsakymas
A three-nucleotide sequence in mRNA. Most codons specify an amino acid; some signal start or stop.
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Klausimas
What is the usual role of the AUG codon?
Atsakymas
It starts translation and specifies methionine. The ribosome uses it to establish the reading frame.
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Klausimas
What happens during translation?
Atsakymas
A ribosome reads mRNA and joins amino acids into a polypeptide. Transfer RNAs match codons with amino acids.
446 kortelės
ATI TEAS 7 Science Flashcards: A&P, Biology, Chemistry & Scientific Reasoning
Mokytis iš šio rinkinio nemokamaiAtsidarys Nibomo ir galėsite pradėti mokytis.
224 kortelė
Klausimas
What is transfer RNA's role in protein synthesis?
Atsakymas
It carries an amino acid and matches its anticodon to an mRNA codon. This places the correct amino acid in sequence.
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Klausimas
What is an anticodon?
Atsakymas
A three-base sequence on tRNA complementary to an mRNA codon. Pairing helps decode the message.
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Klausimas
What is a mutation?
Atsakymas
A change in a DNA sequence. Its effect may be harmful, neutral, or beneficial depending on location and context.
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Klausimas
Why can a one-base insertion in a coding sequence have a large effect?
Atsakymas
It can shift the reading frame. Every downstream codon may change until a stop signal appears.
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Klausimas
Why can changing one amino acid alter a protein's function?
Atsakymas
Amino-acid sequence helps determine folding and shape. Shape controls many protein interactions.
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Klausimas
What is ribosomal RNA's role in protein synthesis?
Atsakymas
It forms the structural and catalytic core of ribosomes. Ribosomal RNA helps align translation components and catalyzes peptide-bond formation.
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Klausimas
Why can different cell types contain the same DNA but perform different jobs?
Atsakymas
They express different sets of genes. Different proteins give cells different structures and functions.
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Klausimas
Which mutation can be passed to offspring?
Atsakymas
A mutation present in a gamete-forming lineage. A mutation limited to ordinary body cells is not inherited through reproduction.
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Klausimas
What is an allele?
Atsakymas
An alternative version of a gene. Diploid individuals usually carry two alleles for each autosomal gene.
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Klausimas
What is genotype?
Atsakymas
An organism's allele combination for a gene or set of genes. Genotype contributes to phenotype.
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Klausimas
What does homozygous mean?
Atsakymas
Having two identical alleles for a gene. Examples include AA and aa.
235 kortelė
Klausimas
What makes an allele dominant in a simple Mendelian trait?
Atsakymas
One copy is enough for its phenotype to appear in a heterozygote. Dominant does not mean common or beneficial.
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Klausimas
What does Mendel's law of segregation describe?
Atsakymas
The two alleles for a gene separate during gamete formation. Each gamete receives one allele.
237 kortelė
Klausimas
What is phenotype?
Atsakymas
An observable trait or characteristic. It can reflect genotype, environment, and their interaction.
238 kortelė
Klausimas
What does heterozygous mean?
Atsakymas
Having two different alleles for a gene. An example is Aa.
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Klausimas
When does a recessive phenotype usually appear in a simple autosomal trait?
Atsakymas
When both alleles are recessive. A heterozygote carries the allele without showing that phenotype.
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Klausimas
When does independent assortment apply most clearly?
Atsakymas
When genes are on different chromosomes or far apart on the same chromosome. Their allele pairs enter gametes independently.
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Klausimas
What does a Punnett square predict?
Atsakymas
Expected offspring genotype probabilities from specified parental gametes. It does not guarantee outcomes in a small family.
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Klausimas
For Aa × Aa, what is the chance of an aa offspring?
Atsakymas
One fourth, or 25%. The genotype ratio is expected to be 1 AA : 2 Aa : 1 aa.
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Klausimas
For Aa × Aa with complete dominance, what phenotypic ratio is expected?
Atsakymas
Three dominant-phenotype offspring to one recessive-phenotype offspring. This is a probability across many offspring.
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Klausimas
How can a test cross reveal the genotype behind a dominant phenotype?
Atsakymas
Cross the individual with a homozygous recessive partner. Recessive offspring show that the unknown parent carried a recessive allele.
245 kortelė
Klausimas
What happens in incomplete dominance?
Atsakymas
A heterozygote has an intermediate phenotype. Neither allele fully masks the other.
246 kortelė
Klausimas
How is the probability of two independent genetic events both occurring found?
Atsakymas
Multiply their individual probabilities. This is the product rule.
247 kortelė
Klausimas
What does a pedigree show?
Atsakymas
How a trait appears across generations of a family. Its pattern can suggest a mode of inheritance.
248 kortelė
Klausimas
Why can two parents have offspring ratios that differ from a Punnett-square expectation?
Atsakymas
Each fertilization is a chance event. Expected ratios become more apparent with larger numbers of offspring.
249 kortelė
Klausimas
What happens in codominance?
Atsakymas
Both alleles are distinctly expressed in a heterozygote. The AB blood type is a common example.
250 kortelė
Klausimas
What are major roles of carbohydrates?
Atsakymas
Providing quick energy, storing energy, and forming some structures. Monosaccharides are their basic building blocks.
251 kortelė
Klausimas
What is a monomer?
Atsakymas
A small building block that can join with others to form a larger molecule. Glucose, amino acids, and nucleotides are examples in different classes.
252 kortelė
Klausimas
What happens in a dehydration-synthesis reaction?
Atsakymas
Monomers join while water is removed. The reaction builds a larger biological molecule.
253 kortelė
Klausimas
What does an enzyme do?
Atsakymas
It lowers activation energy and speeds a reaction without being consumed. Its shape helps it bind specific substrates.
254 kortelė
Klausimas
What are major roles of lipids?
Atsakymas
Long-term energy storage, membranes, insulation, and signaling. Lipids are mostly nonpolar and do not mix well with water.
255 kortelė
Klausimas
What does it mean for a protein to denature?
Atsakymas
Its normal shape is disrupted. Heat, extreme pH, or chemicals can reduce its function.
256 kortelė
Klausimas
What happens during hydrolysis?
Atsakymas
Water is used to split a larger molecule into smaller units. Digestion often uses hydrolysis reactions.
257 kortelė
Klausimas
Why do phospholipids form bilayers in water?
Atsakymas
Their hydrophilic heads interact with water while hydrophobic tails turn inward. This arrangement forms cell-membrane structure.
258 kortelė
Klausimas
What are proteins built from?
Atsakymas
Amino acids linked by peptide bonds. Their folded shapes support enzymes, transport, signaling, structure, and movement.
259 kortelė
Klausimas
How do starch and glycogen compare?
Atsakymas
Both store glucose; plants use starch and animals use glycogen. Their branching patterns differ.
260 kortelė
Klausimas
How do saturated and unsaturated fatty acids differ?
Atsakymas
Saturated fatty acids lack carbon-carbon double bonds; unsaturated ones have one or more. Double bonds often introduce bends.
261 kortelė
Klausimas
What immediate energy-carrying molecule powers many cell processes?
Atsakymas
ATP. Energy released from nutrients can be transferred into ATP's phosphate bonds.
262 kortelė
Klausimas
What are nucleic acids built from?
Atsakymas
Nucleotides. DNA stores hereditary information, while RNA performs several roles in gene expression.
263 kortelė
Klausimas
Which elements are common in all four major biological macromolecule classes?
Atsakymas
Carbon, hydrogen, and oxygen. Nitrogen and phosphorus occur prominently in some classes.
264 kortelė
Klausimas
Why is three-dimensional shape important for macromolecules?
Atsakymas
Shape determines many interactions and functions. A changed shape can prevent a molecule from binding its target.
265 kortelė
Klausimas
What are triglycerides built from?
Atsakymas
One glycerol molecule and three fatty acids. They join through ester bonds to form a common energy-storage lipid.
266 kortelė
Klausimas
What is a pathogen?
Atsakymas
An agent capable of causing disease. Not every microorganism is pathogenic.
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Klausimas
What type of cell is a bacterium?
Atsakymas
A prokaryotic cell. Bacteria usually reproduce by binary fission.
268 kortelė
Klausimas
What cell type do fungi have?
Atsakymas
Eukaryotic cells. Some fungi are unicellular yeasts, while others form multicellular filaments.
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Klausimas
What does disease transmission describe?
Atsakymas
How an infectious agent moves to a susceptible host. Routes include contact, droplets, airborne spread, food, water, and vectors.
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Klausimas
What is a biological vector?
Atsakymas
An organism that becomes infected with a pathogen and transmits it between hosts. The pathogen survives or reproduces inside the vector, unlike transport by a mechanical carrier.
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Klausimas
Why are viruses dependent on host cells?
Atsakymas
They lack the complete machinery for reproduction and metabolism. They use host components to make new virus particles.
272 kortelė
Klausimas
What is a protist?
Atsakymas
A diverse eukaryote that is not classified as an animal, plant, or fungus. Some protists cause disease, while many do not.
273 kortelė
Klausimas
Why do antibiotics not treat viral infections?
Atsakymas
They target bacterial structures or processes that viruses lack. Antiviral drugs use different targets.
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Klausimas
How can normal microbiota protect a host?
Atsakymas
They occupy space and use resources that pathogens might otherwise exploit. Some also support digestion or immune development.
275 kortelė
Klausimas
How does sterilization differ from disinfection?
Atsakymas
Sterilization destroys or removes all microbial life, including resistant forms; disinfection reduces pathogens on objects. The required method depends on use.
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Klausimas
How do infection and disease differ?
Atsakymas
Infection means an agent is established in a host; disease means normal function is impaired and signs or symptoms occur. Infection may be asymptomatic.
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Klausimas
How can breaking a transmission route reduce infectious disease?
Atsakymas
It interrupts the chain connecting a source with a susceptible host. Hand hygiene, clean water, ventilation, and vector control target different links.
278 kortelė
Klausimas
What is an atom?
Atsakymas
The smallest unit of an element that retains that element's chemical identity. Atoms contain a nucleus surrounded by electrons.
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Klausimas
What charge and location does an electron have?
Atsakymas
Negative charge in the electron cloud around the nucleus. Electrons drive most chemical bonding.
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Klausimas
Why are valence electrons important?
Atsakymas
They participate most directly in bonding and reactions. Their arrangement helps predict chemical behavior.
281 kortelė
Klausimas
What do elements in the same periodic-table group often share?
Atsakymas
Similar valence-electron patterns and chemical properties. A group is a vertical column.
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Klausimas
What is an ion?
Atsakymas
An atom or group of atoms with a net electric charge. Its total numbers of protons and electrons are unequal.
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Klausimas
What charge and location does a proton have?
Atsakymas
Positive charge in the nucleus. The number of protons determines the element.
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Klausimas
What does an element's atomic number equal?
Atsakymas
Its number of protons. A neutral atom has the same number of electrons.
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Klausimas
How does a neutral atom form a cation?
Atsakymas
By losing one or more electrons. It has more protons than electrons and a positive charge.
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Klausimas
An atom has 8 protons. How many electrons does it have if it is neutral?
Atsakymas
Eight electrons. Neutral atoms have equal positive and negative charges.
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Klausimas
What charge and location does a neutron have?
Atsakymas
No electric charge, in the nucleus. Neutron number can vary among isotopes of an element.
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Klausimas
What does mass number equal?
Atsakymas
Protons plus neutrons in one atom. It is a whole number for a specific isotope.
289 kortelė
Klausimas
How does a neutral atom form an anion?
Atsakymas
By gaining one or more electrons. It has more electrons than protons and a negative charge.
290 kortelė
Klausimas
What does a period represent on the periodic table?
Atsakymas
A horizontal row. Moving across a period changes proton number one element at a time.
291 kortelė
Klausimas
What are isotopes?
Atsakymas
Atoms of the same element with different numbers of neutrons. They have the same atomic number but different mass numbers.
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Klausimas
What is matter?
Atsakymas
Anything that has mass and occupies space. Solids, liquids, gases, and plasma are forms of matter.
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Klausimas
What distinguishes a solid from a liquid or gas?
Atsakymas
A solid has a definite shape and volume. Its particles vibrate around relatively fixed positions.
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Klausimas
What is a physical change?
Atsakymas
A change in form or state without changing chemical identity. Melting and cutting are examples.
295 kortelė
Klausimas
What is a physical property?
Atsakymas
A characteristic observed without changing a substance's identity. Density, color, and melting point are examples.
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Klausimas
How does an element differ from a compound?
Atsakymas
An element contains one kind of atom; a compound contains elements chemically combined in fixed proportions. Chemical methods can separate a compound into simpler substances.
297 kortelė
Klausimas
What distinguishes a liquid?
Atsakymas
It has a definite volume but takes the shape of its container. Its particles remain close while moving past one another.
298 kortelė
Klausimas
What is a chemical change?
Atsakymas
A process that forms one or more substances with new chemical identities. Bond rearrangement occurs.
299 kortelė
Klausimas
What is a chemical property?
Atsakymas
A substance's ability to undergo a particular chemical change. Flammability and reactivity with acid are examples.
300 kortelė
Klausimas
Which phase changes connect solids and liquids?
Atsakymas
Melting changes a solid to a liquid; freezing changes a liquid to a solid. These are opposite physical changes.
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Klausimas
How does a pure substance differ from a mixture?
Atsakymas
A pure substance has a fixed composition and is an element or compound; a mixture has variable composition and physically combined components. Mixture components retain their identities.
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Klausimas
What distinguishes a gas?
Atsakymas
It has neither a definite shape nor a definite volume. It expands to fill its container.
303 kortelė
Klausimas
What is the formula for density?
Atsakymas
Density = mass ÷ volume. Density is an intensive property.
304 kortelė
Klausimas
Which phase changes connect liquids and gases?
Atsakymas
Vaporization changes a liquid to a gas; condensation changes a gas to a liquid. Evaporation is vaporization at a liquid's surface.
305 kortelė
Klausimas
What is a mixture?
Atsakymas
Two or more substances physically combined in variable proportions. Its components retain their chemical identities.
306 kortelė
Klausimas
How do intensive and extensive properties differ?
Atsakymas
Intensive properties do not depend on sample amount; extensive properties do. Density and temperature are intensive, while mass and volume are extensive.
307 kortelė
Klausimas
A 20 g sample occupies 5 mL. What is its density?
Atsakymas
4 g/mL. Divide 20 g by 5 mL.
308 kortelė
Klausimas
Which phase changes connect solids and gases directly?
Atsakymas
Sublimation changes a solid to a gas; deposition changes a gas to a solid. Neither transition passes through the liquid state.
309 kortelė
Klausimas
How do homogeneous and heterogeneous mixtures differ?
Atsakymas
A homogeneous mixture is uniform throughout; a heterogeneous mixture is not. A solution is homogeneous.
310 kortelė
Klausimas
Where are reactants and products written in a chemical equation?
Atsakymas
Reactants are on the left; products are on the right. The arrow shows the direction represented.
311 kortelė
Klausimas
Why must a chemical equation be balanced?
Atsakymas
Atoms are conserved in ordinary chemical reactions. Each element must have the same atom count on both sides.
312 kortelė
Klausimas
What does a coefficient in a chemical equation change?
Atsakymas
The number of whole particles or moles represented. It multiplies every atom in the following formula.
313 kortelė
Klausimas
Why should subscripts not be changed when balancing an equation?
Atsakymas
Changing a subscript changes the substance's identity. Balancing changes coefficients only.
314 kortelė
Klausimas
What coefficients balance H₂ + O₂ → H₂O?
Atsakymas
2, 1, 2: 2H₂ + O₂ → 2H₂O. Both sides then contain four hydrogen atoms and two oxygen atoms.
315 kortelė
Klausimas
What pattern defines a synthesis reaction?
Atsakymas
Two or more reactants form a more complex product. A general pattern is A + B → AB.
316 kortelė
Klausimas
What are typical products when a hydrocarbon burns completely in oxygen?
Atsakymas
Carbon dioxide and water. Incomplete combustion can produce carbon monoxide or carbon.
317 kortelė
Klausimas
What is the net ionic equation for a typical strong acid–strong base neutralization?
Atsakymas
H⁺(aq) + OH⁻(aq) → H₂O(l). The remaining ions are spectators and do not appear in the net ionic equation.
318 kortelė
Klausimas
What is a precipitate?
Atsakymas
An insoluble solid that forms from substances in solution. Its appearance can signal a chemical reaction.
319 kortelė
Klausimas
What pattern defines a decomposition reaction?
Atsakymas
One compound breaks into simpler products. A general pattern is AB → A + B.
320 kortelė
Klausimas
What is an exothermic reaction?
Atsakymas
A reaction that releases heat to the surroundings. The surroundings often warm.
321 kortelė
Klausimas
What occurs in an oxidation-reduction reaction?
Atsakymas
Electrons transfer or atoms change oxidation state. Oxidation is electron loss; reduction is electron gain.
322 kortelė
Klausimas
What is activation energy?
Atsakymas
The minimum energy barrier reactants must overcome to react. Catalysts lower this barrier.
323 kortelė
Klausimas
Which observations can provide evidence of a chemical reaction?
Atsakymas
Gas formation, a precipitate, sustained color change, light, or temperature change. No single sign proves a reaction without context.
324 kortelė
Klausimas
What is an endothermic reaction?
Atsakymas
A reaction that absorbs heat from the surroundings. The surroundings may cool.
325 kortelė
Klausimas
Why does raising temperature usually speed a reaction?
Atsakymas
Particles collide more often and with greater energy. More collisions overcome activation energy.
326 kortelė
Klausimas
Why can higher reactant concentration increase reaction rate?
Atsakymas
More reactant particles occupy a given volume. This raises collision frequency.
327 kortelė
Klausimas
Why does powdered solid often react faster than one large piece?
Atsakymas
Powder exposes more surface area. More particles are available for collisions.
328 kortelė
Klausimas
How does a catalyst speed a reaction?
Atsakymas
It provides a pathway with lower activation energy. The catalyst is regenerated rather than consumed overall.
329 kortelė
Klausimas
How can increasing pressure affect a reaction between gases?
Atsakymas
It can increase rate by bringing gas particles closer together. Collision frequency rises when volume falls.
330 kortelė
Klausimas
What does a reaction inhibitor do?
Atsakymas
It slows a reaction. It may block a pathway, interfere with a catalyst, or remove reactive intermediates.
331 kortelė
Klausimas
Why can very high temperature slow an enzyme-catalyzed reaction?
Atsakymas
The enzyme can denature and lose its active shape. Moderate warming helps only within the enzyme's stable range.
332 kortelė
Klausimas
What is dynamic equilibrium?
Atsakymas
Forward and reverse reactions continue at equal rates. Concentrations remain constant even though particles still react.
333 kortelė
Klausimas
Does a catalyst change the final equilibrium amounts?
Atsakymas
No. It speeds forward and reverse reactions, so equilibrium is reached sooner without changing its position.
334 kortelė
Klausimas
At equilibrium, what usually happens when the concentration of a dissolved or gaseous reactant increases?
Atsakymas
The system shifts toward consuming some added reactant. It forms more product until a new equilibrium is reached.
335 kortelė
Klausimas
What is a solution?
Atsakymas
A homogeneous mixture. Its components are uniformly distributed at the molecular or ionic level.
336 kortelė
Klausimas
How do solute and solvent differ?
Atsakymas
The solute is dissolved; the solvent is the dissolving medium. The solvent is often present in greater amount.
337 kortelė
Klausimas
What does aqueous mean in chemistry?
Atsakymas
Dissolved in water. The symbol
(aq)marks an aqueous species in an equation.338 kortelė
Klausimas
What does concentration describe?
Atsakymas
The amount of solute in a given amount of solution or solvent. Different units express it in different ways.
339 kortelė
Klausimas
What is molarity?
Atsakymas
Moles of solute per liter of solution. Its unit is mol/L, written M.
340 kortelė
Klausimas
What is the molarity of 0.50 mol solute in 2.0 L of solution?
Atsakymas
0.25 M. Divide 0.50 mol by 2.0 L.
341 kortelė
Klausimas
What stays constant when water is added to dilute a solution without reaction?
Atsakymas
The moles of solute. Volume increases and concentration decreases.
342 kortelė
Klausimas
Which equation relates concentration and volume before and after a dilution?
Atsakymas
M₁V₁ = M₂V₂. It follows from conserving the amount of solute.
343 kortelė
Klausimas
What is solubility?
Atsakymas
The maximum concentration of a solute that can be achieved in a solution at equilibrium under specified conditions. Temperature and the substances involved matter.
344 kortelė
Klausimas
What is a saturated solution?
Atsakymas
A solution holding the maximum dissolved solute at those conditions. Extra solute remains undissolved at equilibrium.
345 kortelė
Klausimas
What is an electrolyte?
Atsakymas
A substance that produces mobile ions in solution and conducts electricity. Soluble ionic compounds are common examples.
346 kortelė
Klausimas
What does 'like dissolves like' predict?
Atsakymas
Substances with similar polarity tend to mix well. Polar solvents favor polar or ionic solutes; nonpolar solvents favor nonpolar solutes.
347 kortelė
Klausimas
Does heating always increase solubility?
Atsakymas
No. Many solids become more soluble in water, but gases usually become less soluble as temperature rises.
348 kortelė
Klausimas
What is an unsaturated solution?
Atsakymas
A solution that can dissolve more solute at the stated conditions. It is below the solubility limit.
349 kortelė
Klausimas
What does a Brønsted-Lowry acid donate?
Atsakymas
A proton, H⁺. In water, acid behavior increases hydronium-ion concentration.
350 kortelė
Klausimas
What does pH describe?
Atsakymas
The hydronium-ion concentration on a logarithmic scale. Lower pH means higher hydronium concentration.
351 kortelė
Klausimas
At 25 °C, what pH range is acidic?
Atsakymas
Below 7. A neutral aqueous solution is pH 7 at this temperature.
352 kortelė
Klausimas
How does hydronium concentration change when pH drops by 1 unit?
Atsakymas
It increases tenfold. The pH scale is logarithmic.
353 kortelė
Klausimas
What does a Brønsted-Lowry base accept?
Atsakymas
A proton, H⁺. Many bases in water also increase hydroxide-ion concentration.
354 kortelė
Klausimas
At 25 °C, what is the relationship between pH and pOH?
Atsakymas
pH + pOH = 14. pOH is the negative base-10 logarithm of hydroxide-ion concentration; this relation applies to aqueous solutions at 25 °C.
355 kortelė
Klausimas
At 25 °C, what pH range is basic?
Atsakymas
Above 7. Basic solutions have less hydronium and more hydroxide than neutral water.
356 kortelė
Klausimas
What are typical products of a strong acid reacting with a strong base?
Atsakymas
Water and an ionic salt. Hydrogen ions and hydroxide ions combine to form water.
357 kortelė
Klausimas
What does strong mean for an acid or base?
Atsakymas
It produces its characteristic ions essentially completely in water. Strong acids ionize; soluble ionic strong bases dissociate. Strength is separate from concentration.
358 kortelė
Klausimas
What does a buffer do?
Atsakymas
It resists large pH changes when small amounts of acid or base are added. A weak conjugate acid-base pair neutralizes much of the added H₃O⁺ or OH⁻.
359 kortelė
Klausimas
How does an acid-base indicator work?
Atsakymas
Its color depends on pH. The change occurs over a characteristic pH range.
360 kortelė
Klausimas
A solution has pH 9 at 25 °C. What is its pOH?
Atsakymas
5. Subtract the pH from 14.
361 kortelė
Klausimas
How does a concentrated weak acid differ from a dilute strong acid?
Atsakymas
Concentration tells how much acid is present; strength tells how completely it ionizes. A concentrated weak acid contains more partially ionizing acid, while a dilute strong acid contains less acid that ionizes essentially completely. Either can have the lower pH.
362 kortelė
Klausimas
What is the SI base unit of length?
Atsakymas
The meter (m). Centimeters and millimeters are decimal subdivisions of a meter.
363 kortelė
Klausimas
Which tool directly measures mass in a laboratory?
Atsakymas
A balance. A spring scale measures force, often reported as weight.
364 kortelė
Klausimas
What is the SI base unit of mass?
Atsakymas
The kilogram (kg). Laboratory mass is also commonly reported in grams.
365 kortelė
Klausimas
A student needs to measure about 35 mL of liquid and can choose a beaker or graduated cylinder. Which should they use?
Atsakymas
A graduated cylinder. Read the scale at eye level.
366 kortelė
Klausimas
What is the SI base unit of time?
Atsakymas
The second (s). Minutes and hours are accepted for many everyday uses.
367 kortelė
Klausimas
Where should the volume of a clear water-based liquid be read in a graduated cylinder?
Atsakymas
At the bottom of the meniscus. Keep your eye level with the liquid surface.
368 kortelė
Klausimas
What is the SI base unit of thermodynamic temperature?
Atsakymas
The kelvin (K). Degrees Celsius are widely used for laboratory and body temperatures.
369 kortelė
Klausimas
Which tool measures temperature?
Atsakymas
A thermometer. Its range and resolution should match the task.
370 kortelė
Klausimas
What factor does the metric prefix kilo- represent?
Atsakymas
One thousand, or 10³. One kilometer equals 1,000 meters.
371 kortelė
Klausimas
A ruler's smallest marking is 1 mm. To what place should a careful analog reading usually be estimated?
Atsakymas
One place beyond the smallest marking, when the scale allows it. The final digit is uncertain.
372 kortelė
Klausimas
What is measurement accuracy?
Atsakymas
Closeness to an accepted or true value. A systematic error can make precise measurements inaccurate.
373 kortelė
Klausimas
How do mass and weight differ?
Atsakymas
Mass is the amount of matter; weight is gravitational force on that mass. Mass stays constant when gravity changes, but weight does not.
374 kortelė
Klausimas
What factor does the metric prefix milli- represent?
Atsakymas
One thousandth, or 10⁻³. One milliliter is 0.001 liter.
375 kortelė
Klausimas
How can the volume of an irregular solid be measured with water?
Atsakymas
Use water displacement. Subtract the initial water volume from the final volume after submerging the object.
376 kortelė
Klausimas
What is measurement precision?
Atsakymas
Closeness of repeated measurements to one another. Precise results can still be consistently wrong.
377 kortelė
Klausimas
What is an instrument's resolution?
Atsakymas
The smallest change it can meaningfully display or distinguish. Higher resolution does not automatically guarantee accuracy.
378 kortelė
Klausimas
How many centimeters are in 2.5 meters?
Atsakymas
2.5 × 10² cm (250 cm). Multiply meters by the exact conversion factor 100 cm/m.
379 kortelė
Klausimas
Why must a numerical measurement include a unit?
Atsakymas
The unit identifies the quantity's scale. A bare number is ambiguous and cannot be compared reliably.
380 kortelė
Klausimas
What is a scientific observation?
Atsakymas
Information recorded with senses or instruments. It should be distinguished from an explanation of what was observed.
381 kortelė
Klausimas
What makes a hypothesis scientifically useful?
Atsakymas
It is testable and falsifiable. Evidence must be able to count against it.
382 kortelė
Klausimas
What is a scientific theory?
Atsakymas
A broad, well-supported explanation of natural phenomena. It is not a casual guess and can be revised with new evidence.
383 kortelė
Klausimas
Which claim is falsifiable: 'No possible observation could count against this treatment's effectiveness' or 'This treatment lowers mean temperature within one hour'?
Atsakymas
The claim that the treatment lowers mean temperature within one hour. An observation could count against it, so evidence can test it.
384 kortelė
Klausimas
What is an inference?
Atsakymas
A logical interpretation based on observations and prior knowledge. It goes beyond the raw measurement.
385 kortelė
Klausimas
How does a prediction relate to a hypothesis?
Atsakymas
It states an expected result if the hypothesis is correct. Experiments compare observed results with that expectation.
386 kortelė
Klausimas
How does a scientific law differ from a scientific theory?
Atsakymas
A law describes a consistent pattern; a theory explains how or why patterns occur. One does not mature into the other.
387 kortelė
Klausimas
What does reliability mean for a measurement or procedure?
Atsakymas
It produces consistent results under the same conditions. Repetition helps assess reliability.
388 kortelė
Klausimas
What does a correlation show?
Atsakymas
Two variables change together in a patterned way. Correlation alone does not establish that one causes the other.
389 kortelė
Klausimas
What is bias in scientific work?
Atsakymas
A systematic influence that pushes observations, selection, or interpretation in one direction. Good design tries to prevent or measure it.
390 kortelė
Klausimas
What is the purpose of scientific peer review?
Atsakymas
Independent experts evaluate methods, reasoning, and reporting before publication. It improves scrutiny but does not guarantee truth.
391 kortelė
Klausimas
What does validity ask about a study or measurement?
Atsakymas
Whether it measures or tests what it claims to measure or test. Consistency alone does not ensure validity.
392 kortelė
Klausimas
What evidence most strengthens a causal claim?
Atsakymas
A well-controlled experiment that manipulates the suspected cause. Random assignment reduces confounding, while independent replication tests whether the result holds with new data.
393 kortelė
Klausimas
What is a primary scientific source?
Atsakymas
A report of original methods, data, and results. A review article synthesizes many primary studies.
394 kortelė
Klausimas
How should an unexpected outlier be handled?
Atsakymas
Investigate and report it rather than deleting it automatically. Exclusion needs a documented scientific reason.
395 kortelė
Klausimas
What is a confounding variable?
Atsakymas
An outside factor related to both the suspected cause and the outcome. It can create a misleading association.
396 kortelė
Klausimas
Why should a sample represent the population of interest?
Atsakymas
Results generalize poorly when important groups are missing or overrepresented. Sampling method matters as much as size.
397 kortelė
Klausimas
What is a scientific model?
Atsakymas
A simplified representation used to explain or predict a system. A model is useful within its assumptions and limits.
398 kortelė
Klausimas
Why should measurements report uncertainty or reasonable precision?
Atsakymas
Every measurement has limits. Reporting more digits than the method supports creates false precision.
399 kortelė
Klausimas
If results match a prediction once, what is the safest conclusion?
Atsakymas
The results support the hypothesis under those conditions. One result does not prove the hypothesis in every setting.
400 kortelė
Klausimas
What is a direct relationship between two variables?
Atsakymas
As one increases, the other tends to increase; as one decreases, the other tends to decrease. The relationship need not be perfectly linear.
401 kortelė
Klausimas
Which variable is usually placed on the x-axis of an experimental graph?
Atsakymas
The independent variable. It is the factor selected or changed by the investigator.
402 kortelė
Klausimas
What does the slope of a straight-line graph represent?
Atsakymas
Change in y divided by change in x. It is the response rate per unit change in the other variable.
403 kortelė
Klausimas
A line rises 12 units in y while x rises 3 units. What is its slope?
Atsakymas
4 units of y per unit of x. Divide 12 by 3.
404 kortelė
Klausimas
What is an inverse relationship?
Atsakymas
As one variable increases, the other tends to decrease. Their product is constant only in a strictly inverse proportion.
405 kortelė
Klausimas
Which variable is usually placed on the y-axis of an experimental graph?
Atsakymas
The dependent variable. It is the measured response.
406 kortelė
Klausimas
What does a plateau on a response graph indicate?
Atsakymas
The measured response has stopped changing much despite further x increases. A limiting factor may have been reached.
407 kortelė
Klausimas
What is interpolation?
Atsakymas
Estimating a value within the range of measured data. It is generally safer than extrapolating beyond that range.
408 kortelė
Klausimas
What pattern suggests no relationship between two plotted variables?
Atsakymas
The response shows no consistent change as the other variable changes. Points may scatter without a trend.
409 kortelė
Klausimas
Before comparing values in a data table, what should you check?
Atsakymas
Headings, units, and conditions. Numbers from different measures or scales cannot be compared directly.
410 kortelė
Klausimas
If 3 samples require 12 mL total, how much is needed for 5 equal samples?
Atsakymas
20 mL. The rate is 4 mL per sample, so multiply by 5.
411 kortelė
Klausimas
How is the arithmetic mean calculated?
Atsakymas
Add all values and divide by the number of values. A large outlier can shift the mean.
412 kortelė
Klausimas
Why is extrapolation uncertain?
Atsakymas
It assumes the observed trend continues outside measured conditions. The relationship may change beyond the data range.
413 kortelė
Klausimas
A culture grows from 20 to 50 cells in 6 hours. What is the average growth rate?
Atsakymas
5 cells per hour. The change is 30 cells divided by 6 hours.
414 kortelė
Klausimas
A measurement rises from 40 to 50. What is the percent increase?
Atsakymas
25%. The increase is 10, and 10 ÷ 40 × 100 = 25%.
415 kortelė
Klausimas
When can the median describe a typical value better than the mean?
Atsakymas
When data are skewed or contain strong outliers. In an ordered set, the median is the middle value for an odd count and the mean of the two middle values for an even count.
416 kortelė
Klausimas
How do quantitative and qualitative data differ?
Atsakymas
Quantitative data are numerical; qualitative data describe categories or qualities. Both can answer scientific questions.
417 kortelė
Klausimas
A response is 2 at dose 1, 4 at dose 2, and 8 at dose 4. If the relationship is linear, what response is predicted at dose 3?
Atsakymas
6. The observed rate is 2 response units per dose unit, so interpolation at dose 3 gives 6.
418 kortelė
Klausimas
How can a graph reveal a nonlinear relationship?
Atsakymas
The points follow a curve rather than a straight line. The rate of change varies across the x-range.
419 kortelė
Klausimas
What is the range of a data set?
Atsakymas
Maximum minus minimum. It describes total spread but ignores the distribution between the endpoints.
420 kortelė
Klausimas
What makes a scientific research question testable?
Atsakymas
It identifies measurable variables or observable outcomes. The needed data must be obtainable.
421 kortelė
Klausimas
In an experiment, what is the independent variable?
Atsakymas
The factor deliberately changed or assigned by the investigator. In a simple one-factor experiment, changing one independent variable helps isolate its effect.
422 kortelė
Klausimas
What should a hypothesis connect?
Atsakymas
A proposed explanation with a measurable outcome. It should lead to a prediction that evidence can challenge.
423 kortelė
Klausimas
What is a controlled variable, or constant?
Atsakymas
A condition kept the same across groups. Holding it constant prevents it from explaining outcome differences.
424 kortelė
Klausimas
What is the purpose of a control group?
Atsakymas
It provides a comparison without the experimental treatment. Differences can then be attributed more confidently to the treatment.
425 kortelė
Klausimas
In an experiment, what is the dependent variable?
Atsakymas
The measured response. It may change because of the independent variable.
426 kortelė
Klausimas
What form can a useful experimental prediction take?
Atsakymas
If the independent variable changes in a stated way, then the dependent variable should respond in a stated way. The reason links it to the hypothesis.
427 kortelė
Klausimas
What does a positive control demonstrate?
Atsakymas
That the setup can produce a known response. If it fails, the test system may be defective.
428 kortelė
Klausimas
Why randomly assign subjects to experimental groups?
Atsakymas
To distribute known and unknown differences more evenly. This reduces selection bias and confounding.
429 kortelė
Klausimas
How can blinding reduce bias?
Atsakymas
It keeps participants, observers, or both unaware of treatment assignments. Expectations are less likely to affect behavior or measurement.
430 kortelė
Klausimas
What is a placebo?
Atsakymas
An inactive treatment designed to resemble the experimental treatment. It helps separate treatment effects from expectation effects.
431 kortelė
Klausimas
What does a negative control demonstrate?
Atsakymas
What happens when the tested cause is absent. An unexpected response may reveal contamination or another source.
432 kortelė
Klausimas
Why does a larger sample often improve a study?
Atsakymas
It reduces the influence of chance variation and supports more stable estimates. It cannot repair a biased sampling method.
433 kortelė
Klausimas
Why repeat trials within an experiment?
Atsakymas
To estimate variability and check consistency. One unusual trial then has less influence.
434 kortelė
Klausimas
Why must an experimental procedure be detailed and standardized?
Atsakymas
So groups are treated consistently and others can reproduce the work. Uncontrolled procedural differences create alternative explanations.
435 kortelė
Klausimas
Why calibrate a measuring instrument before collecting data?
Atsakymas
To compare its readings with a known standard and reduce systematic error. Calibration improves confidence in accuracy.
436 kortelė
Klausimas
What is an operational definition?
Atsakymas
A precise statement of how a variable is measured or manipulated. It turns an abstract concept into a repeatable procedure.
437 kortelė
Klausimas
How does independent replication differ from repeated trials?
Atsakymas
Independent replication repeats a study with independently collected data, often by a different investigator; repeated trials rerun measurements within the original experiment. Replication tests consistency across separate studies.
438 kortelė
Klausimas
Why should raw data be recorded before interpretation?
Atsakymas
It preserves the observations separately from conclusions. Others can check calculations and reasoning.
439 kortelė
Klausimas
What should a scientific conclusion do?
Atsakymas
Answer the research question using the data and acknowledge limits. It should not claim more than the design supports.
440 kortelė
Klausimas
What should happen when data do not support a hypothesis?
Atsakymas
Revise or reject the hypothesis and consider new tests. Data should not be altered to preserve the original idea.
441 kortelė
Klausimas
What is a study limitation?
Atsakymas
A feature that restricts interpretation or generalization. Small samples, short duration, and imperfect measurements are examples.
442 kortelė
Klausimas
Why are ethics part of experimental design?
Atsakymas
Research must protect participants, organisms, and communities while balancing risks and benefits. Consent and humane treatment are key examples.
443 kortelė
Klausimas
How does an observational study differ from an experiment?
Atsakymas
It measures variables without assigning the exposure. It can find associations but usually supports weaker causal conclusions.
444 kortelė
Klausimas
Plants receive 0, 2, or 4 hours of added light, and growth is measured. What is the independent variable?
Atsakymas
Hours of added light. Plant growth is the dependent variable.
445 kortelė
Klausimas
A fertilizer study gives every plant the same water, soil, and temperature. What are these conditions?
Atsakymas
Controlled variables. Keeping them constant isolates the fertilizer's effect.
446 kortelė
Klausimas
A drug group improves more than a control group, but the groups were not randomly assigned. What is the main caution?
Atsakymas
Preexisting group differences could explain some improvement. The result is suggestive, but the design weakens a causal claim.
446 kortelės
ATI TEAS 7 Science Flashcards: A&P, Biology, Chemistry & Scientific Reasoning
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