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.
Tietoja tästä pakasta
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.
Tämän pakan kortit
Kortti 1
Kysymys
What posture defines the standard anatomical position?
Vastaus
Standing upright, facing forward, with arms at the sides and palms forward. The feet point forward, giving anatomy a consistent reference position.
Kortti 2
Kysymys
In anatomical language, what does superior mean?
Vastaus
Toward the head or above another structure. Inferior means toward the feet or below.
Kortti 3
Kysymys
Which anatomical plane divides the body into left and right portions?
Vastaus
The sagittal plane. A midsagittal plane divides the body into equal left and right halves.
Kortti 4
Kysymys
Why does the body use feedback mechanisms?
Vastaus
To regulate internal conditions. Feedback compares a condition with a set range and triggers responses that adjust it.
Kortti 5
Kysymys
What is the order of structural organization from simplest to most complex?
Vastaus
Chemical, cellular, tissue, organ, organ system, organism. Each level builds on interactions at the preceding level.
Kortti 6
Kysymys
What does anterior mean in human anatomy?
Vastaus
Toward the front of the body. Posterior means toward the back.
Kortti 7
Kysymys
Which plane divides the body into upper and lower portions?
Vastaus
The transverse plane. It is also called the horizontal plane.
Kortti 8
Kysymys
What is homeostasis?
Vastaus
The maintenance of a relatively stable internal environment. It is dynamic rather than perfectly unchanging.
Kortti 9
Kysymys
Which major body cavity contains the brain and spinal cord?
Vastaus
The dorsal body cavity. Its cranial cavity holds the brain, and its vertebral cavity holds the spinal cord.
Kortti 10
Kysymys
What does medial mean in anatomical language?
Vastaus
Toward the body's midline. Lateral means farther from the midline.
Kortti 11
Kysymys
A rise in body temperature triggers sweating. What control pattern is this?
Vastaus
Negative feedback. The response opposes the original temperature change and moves the body toward its normal range.
Kortti 12
Kysymys
Which anatomical plane divides the body into front and back portions?
Vastaus
The frontal, or coronal, plane. It separates anterior from posterior portions.
Kortti 13
Kysymys
Which major body cavity contains the thoracic and abdominopelvic cavities?
Vastaus
The ventral body cavity. The diaphragm separates its thoracic and abdominopelvic portions.
Kortti 14
Kysymys
What does proximal mean when describing a limb?
Vastaus
Closer to the limb's point of attachment. Distal means farther from that point.
Kortti 15
Kysymys
How does positive feedback differ from negative feedback?
Vastaus
Positive feedback amplifies the initial change. Negative feedback opposes a change; positive feedback continues until a stopping event occurs.
Kortti 16
Kysymys
Which tissue type covers surfaces and lines body cavities?
Vastaus
Epithelial tissue. It also forms many glands and often serves protective, absorptive, or secretory roles.
Kortti 17
Kysymys
Which tissue type mainly supports, binds, and protects other tissues?
Vastaus
Connective tissue. Its cells are typically separated by an extracellular matrix.
Kortti 18
Kysymys
What shared property lets muscle tissue produce movement?
Vastaus
Contractility. Muscle cells shorten or develop tension in response to stimulation.
Kortti 19
Kysymys
Which tissue type rapidly communicates by electrical signals?
Vastaus
Nervous tissue. Neurons transmit signals, while supporting cells help maintain their environment.
Kortti 20
Kysymys
Why are tightly packed epithelial cells well suited for barriers?
Vastaus
They leave little space between cells. This continuous arrangement limits passage across a surface.
Kortti 21
Kysymys
What distinguishes connective tissue from epithelial tissue?
Vastaus
Connective tissue usually has abundant extracellular matrix. Epithelial cells are more tightly packed.
Kortti 22
Kysymys
What are the four basic human tissue types?
Vastaus
Epithelial, connective, muscle, and nervous tissue. Organs contain two or more tissue types working together.
Kortti 23
Kysymys
What makes a structure an organ rather than a tissue?
Vastaus
An organ combines multiple tissue types for a specific function. A tissue is a group of similar cells and matrix performing related work.
Kortti 24
Kysymys
What are the skeletal system's main functions?
Vastaus
Support, protection, movement, mineral storage, blood-cell production, and fat storage. Bones also provide levers for muscles.
Kortti 25
Kysymys
What belongs to the axial skeleton?
Vastaus
The skull, vertebral column, and thoracic cage. These structures form the body's central axis.
Kortti 26
Kysymys
How do compact and spongy bone differ?
Vastaus
Compact bone is dense; spongy bone has a lattice of trabeculae. Both are organized living bone tissue.
Kortti 27
Kysymys
What is a joint?
Vastaus
A place where two or more bones meet. Joint structure determines how much movement is possible.
Kortti 28
Kysymys
Which bone cell builds new bone matrix?
Vastaus
An osteoblast. Osteoclasts break down bone, while osteocytes maintain mature bone tissue.
Kortti 29
Kysymys
What belongs to the appendicular skeleton?
Vastaus
The limbs plus the shoulder and pelvic girdles. It attaches the limbs to the axial skeleton.
Kortti 30
Kysymys
What is the main role of red bone marrow?
Vastaus
Blood-cell production. This process is called hematopoiesis.
Kortti 31
Kysymys
Which joint class allows the greatest range of motion?
Vastaus
A synovial joint. A fluid-filled joint cavity reduces friction between articulating surfaces.
Kortti 32
Kysymys
Which bone cell breaks down bone matrix?
Vastaus
An osteoclast. Bone resorption helps remodeling and mineral balance.
Kortti 33
Kysymys
What does a ligament connect?
Vastaus
Bone to bone. A tendon connects muscle to bone.
Kortti 34
Kysymys
What is the shaft of a long bone called?
Vastaus
The diaphysis. The enlarged ends are the epiphyses.
Kortti 35
Kysymys
Why is bone important to blood-calcium balance?
Vastaus
Bone stores calcium and can release or absorb it during remodeling. Hormones regulate this exchange.
Kortti 36
Kysymys
What is stored mainly in yellow bone marrow?
Vastaus
Fat. It serves as an energy reserve.
Kortti 37
Kysymys
What does articular cartilage do at a synovial joint?
Vastaus
It reduces friction and absorbs shock. It covers the ends of articulating bones.
Kortti 38
Kysymys
Why must a broken bone receive a blood supply during healing?
Vastaus
Repairing cells need oxygen and nutrients. Restored blood vessels support fracture healing.
Kortti 39
Kysymys
What is bone remodeling?
Vastaus
Continuous removal and replacement of bone tissue. It repairs microdamage and helps bones adapt to stress.
Kortti 40
Kysymys
Which muscle tissue is usually under voluntary control?
Vastaus
Skeletal muscle. Most skeletal muscles move the skeleton, while some, such as facial muscles, insert into skin or other soft tissue.
Kortti 41
Kysymys
What is a sarcomere?
Vastaus
The basic contractile unit of striated muscle. It lies between two Z discs.
Kortti 42
Kysymys
What does a tendon connect?
Vastaus
Muscle to bone. It transmits muscle force to the skeleton.
Kortti 43
Kysymys
Which proteins slide past one another during muscle contraction?
Vastaus
Actin and myosin. Their interaction shortens sarcomeres without shortening the filaments themselves.
Kortti 44
Kysymys
Where is smooth muscle commonly found?
Vastaus
In the walls of hollow organs and blood vessels. Its contractions are generally involuntary.
Kortti 45
Kysymys
What ion exposes binding sites needed for skeletal muscle contraction?
Vastaus
Calcium. Its release inside the muscle fiber allows actin and myosin interaction.
Kortti 46
Kysymys
How do antagonistic muscle pairs move a joint?
Vastaus
One muscle contracts while the opposing muscle relaxes. Reversing their roles moves the joint in the opposite direction.
Kortti 47
Kysymys
Why does muscle contraction require ATP?
Vastaus
ATP powers cross-bridge cycling and ion pumps. It is also needed for myosin to detach from actin.
Kortti 48
Kysymys
Which muscle tissue makes up the heart wall?
Vastaus
Cardiac muscle. It is striated, involuntary, and connected for coordinated pumping.
Kortti 49
Kysymys
During a typical muscle contraction, which attachment moves more: origin or insertion?
Vastaus
The insertion. The origin is generally the more fixed attachment.
Kortti 50
Kysymys
Which type of neuron sends the signal that initiates skeletal-muscle contraction?
Vastaus
A somatic motor neuron. It releases acetylcholine at the neuromuscular junction, triggering an action potential in the muscle fiber.
Kortti 51
Kysymys
What is muscle tone?
Vastaus
Continuous low-level muscle tension. It helps maintain posture and readiness without producing a large movement.
Kortti 52
Kysymys
How does skeletal muscle help regulate body temperature?
Vastaus
Contraction releases heat. Shivering increases rapid contractions when the body is cold.
Kortti 53
Kysymys
What are the three muscle tissue types?
Vastaus
Skeletal, cardiac, and smooth muscle. They differ in location, structure, and control.
Kortti 54
Kysymys
What is a neuron's main function?
Vastaus
To receive, process, and transmit information. Neurons use electrical signals and chemical messengers.
Kortti 55
Kysymys
What structures make up the central nervous system?
Vastaus
The brain and spinal cord. They integrate information and coordinate responses.
Kortti 56
Kysymys
Which part of a neuron usually receives incoming signals?
Vastaus
The dendrites. The cell body integrates much of that input.
Kortti 57
Kysymys
What does the peripheral nervous system include?
Vastaus
Nerves and ganglia outside the brain and spinal cord. It links the central nervous system with the rest of the body.
Kortti 58
Kysymys
Which neuron structure carries an impulse away from the cell body?
Vastaus
The axon. Its terminals communicate with another cell.
Kortti 59
Kysymys
Which nervous-system division controls skeletal muscles voluntarily?
Vastaus
The somatic nervous system. It also carries sensory information from skin, muscles, and joints.
Kortti 60
Kysymys
What is a synapse?
Vastaus
A junction where one neuron communicates with another cell. Chemical synapses use neurotransmitters across a small gap.
Kortti 61
Kysymys
Which nervous-system division regulates organs and glands without conscious control?
Vastaus
The autonomic nervous system. It includes sympathetic and parasympathetic divisions.
Kortti 62
Kysymys
How does myelin affect nerve signaling?
Vastaus
It speeds impulse conduction along an axon. Myelin insulates segments of the axon.
Kortti 63
Kysymys
Which autonomic division prepares the body for acute activity?
Vastaus
The sympathetic division. It generally increases alertness and supports a fight-or-flight response.
Kortti 64
Kysymys
What is a reflex?
Vastaus
A rapid, predictable response to a stimulus. A reflex pathway can act before conscious awareness.
Kortti 65
Kysymys
Which autonomic division supports rest, digestion, and energy conservation?
Vastaus
The parasympathetic division. It generally promotes routine maintenance functions.
Kortti 66
Kysymys
Which brain region is most associated with conscious thought and voluntary movement?
Vastaus
The cerebrum. Its cortex also processes much sensory information.
Kortti 67
Kysymys
Which brain region fine-tunes balance and coordinated movement?
Vastaus
The cerebellum. It compares intended movement with sensory feedback.
Kortti 68
Kysymys
Which brain region controls vital automatic functions such as breathing and heart rate?
Vastaus
The brainstem. It also connects higher brain regions with the spinal cord.
Kortti 69
Kysymys
How do sensory and motor neurons differ?
Vastaus
Sensory neurons carry information toward the CNS; motor neurons carry commands away. Interneurons connect and process signals within the CNS.
Kortti 70
Kysymys
What does a sensory receptor do?
Vastaus
It converts a stimulus into a neural signal. Different receptors respond best to particular forms of energy or chemicals.
Kortti 71
Kysymys
What is a hormone?
Vastaus
A chemical messenger released into body fluids to affect target cells. A target responds only if it has the appropriate receptor.
Kortti 72
Kysymys
Why is the pituitary gland often called a master gland?
Vastaus
Several pituitary hormones regulate other endocrine glands. The hypothalamus controls much of pituitary activity.
Kortti 73
Kysymys
Why can one hormone affect some cells but not others?
Vastaus
Only target cells have the matching receptor. Receptor binding starts the cell's response.
Kortti 74
Kysymys
Which gland produces hormones that broadly increase metabolic activity?
Vastaus
The thyroid gland. Thyroid hormones influence energy use and development.
Kortti 75
Kysymys
What is insulin's main effect on blood glucose?
Vastaus
It lowers blood glucose. Insulin promotes glucose uptake and storage after a meal.
Kortti 76
Kysymys
Which glands release a hormone that raises blood calcium?
Vastaus
The parathyroid glands. Parathyroid hormone acts on bone, kidneys, and vitamin D pathways.
Kortti 77
Kysymys
Which adrenal region releases epinephrine during acute stress?
Vastaus
The adrenal medulla. Its hormones reinforce sympathetic nervous-system effects.
Kortti 78
Kysymys
Which organ has both endocrine and digestive functions?
Vastaus
The pancreas. Its islets release hormones, while other cells release digestive enzymes.
Kortti 79
Kysymys
What is glucagon's main effect on blood glucose?
Vastaus
It raises blood glucose. It promotes release of stored glucose during fasting.
Kortti 80
Kysymys
Rising thyroid hormone reduces its own upstream stimulation. What pattern is this?
Vastaus
Negative feedback. The final hormone limits further release along the control pathway.
Kortti 81
Kysymys
Which adrenal region produces steroid hormones such as cortisol and aldosterone?
Vastaus
The adrenal cortex. It surrounds the adrenal medulla.
Kortti 82
Kysymys
Which gland releases melatonin and helps regulate daily sleep timing?
Vastaus
The pineal gland. Light information influences its secretion pattern.
Kortti 83
Kysymys
Which hormone directly increases collecting-duct water permeability?
Vastaus
Antidiuretic hormone, or ADH. It makes collecting ducts more permeable to water, increasing water reabsorption and usually producing less, more concentrated urine.
Kortti 84
Kysymys
Which hormone strengthens uterine contractions during labor?
Vastaus
Oxytocin. This is a classic positive-feedback pathway that ends after delivery.
Kortti 85
Kysymys
How does endocrine signaling generally differ from nervous signaling?
Vastaus
It is usually slower to start and longer lasting. Hormones travel through body fluids, while neurons signal specific targets rapidly.
Kortti 86
Kysymys
What is plasma?
Vastaus
The liquid portion of blood. It carries cells, nutrients, hormones, proteins, wastes, and dissolved gases.
Kortti 87
Kysymys
Which side of the heart pumps blood to the lungs?
Vastaus
The right side. The right ventricle sends deoxygenated blood through the pulmonary trunk and arteries.
Kortti 88
Kysymys
What is the main function of red blood cells?
Vastaus
Transporting oxygen. Their hemoglobin also carries a smaller share of carbon dioxide.
Kortti 89
Kysymys
What defines an artery?
Vastaus
It carries blood away from the heart. Oxygen content does not define it; pulmonary arteries carry deoxygenated blood.
Kortti 90
Kysymys
What is the main function of white blood cells?
Vastaus
Body defense. Different white blood cells recognize, attack, or coordinate responses to threats.
Kortti 91
Kysymys
Which side of the heart pumps blood into systemic circulation?
Vastaus
The left side. The left ventricle sends oxygenated blood into the aorta.
Kortti 92
Kysymys
What is the main purpose of heart valves?
Vastaus
To keep blood moving in one direction. Pressure differences open and close them.
Kortti 93
Kysymys
What defines a vein?
Vastaus
It carries blood toward the heart. Many veins contain valves that limit backflow.
Kortti 94
Kysymys
What is the main role of platelets?
Vastaus
Helping stop bleeding. They form a platelet plug and support clotting reactions at a damaged vessel.
Kortti 95
Kysymys
Why are capillaries well suited for exchange?
Vastaus
Their walls are only one cell layer thick. Their small diameter and large total surface area support diffusion and filtration.
Kortti 96
Kysymys
After blood enters the right atrium, what chamber receives it next?
Vastaus
The right ventricle. Blood passes through the tricuspid valve before entering that chamber.
Kortti 97
Kysymys
What happens during ventricular systole?
Vastaus
The ventricles contract and eject blood. The right ventricle pumps to the lungs, and the left pumps to the body.
Kortti 98
Kysymys
What is pulmonary circulation?
Vastaus
Blood flow between the heart and lungs. It allows gas exchange and returns oxygenated blood to the left atrium.
Kortti 99
Kysymys
What normally sets the heart's rhythm?
Vastaus
The sinoatrial, or SA, node. Its spontaneous electrical activity initiates each heartbeat.
Kortti 100
Kysymys
What molecule in red blood cells binds oxygen?
Vastaus
Hemoglobin. Its iron-containing heme groups bind oxygen reversibly.
Kortti 101
Kysymys
What happens during ventricular diastole?
Vastaus
The ventricles relax and fill. Atrioventricular valves are open during most ventricular filling.
Kortti 102
Kysymys
What is systemic circulation?
Vastaus
Blood flow between the heart and the body's tissues. It delivers oxygen and nutrients and returns wastes.
Kortti 103
Kysymys
What does arterial blood pressure measure?
Vastaus
The force of blood against artery walls. It is commonly reported as systolic over diastolic pressure.
Kortti 104
Kysymys
What do coronary arteries supply?
Vastaus
The heart muscle itself. Blocked coronary blood flow can deprive myocardium of oxygen.
Kortti 105
Kysymys
Which major vessels return systemic blood to the right atrium?
Vastaus
The superior and inferior venae cavae. The superior vessel drains the upper body; the inferior drains the lower body.
Kortti 106
Kysymys
What is the respiratory system's primary gas-exchange function?
Vastaus
Bringing oxygen into the body and removing carbon dioxide. Ventilation moves air, while diffusion exchanges gases.
Kortti 107
Kysymys
What is the airflow sequence from the pharynx to the gas-exchange surfaces?
Vastaus
Pharynx, larynx, trachea, bronchi, bronchioles, alveoli. Each branch conducts air deeper into the lungs.
Kortti 108
Kysymys
Where does most gas exchange occur in the lungs?
Vastaus
Across the alveolar-capillary membrane. Thin walls and a large surface area shorten diffusion distance.
Kortti 109
Kysymys
What does the diaphragm do during quiet inhalation?
Vastaus
It contracts and moves downward. Thoracic volume rises, lung pressure falls, and air flows inward.
Kortti 110
Kysymys
Why does oxygen move from alveoli into pulmonary capillaries?
Vastaus
Its partial pressure is higher in alveolar air than in incoming blood. Oxygen diffuses down that gradient.
Kortti 111
Kysymys
What drives quiet exhalation?
Vastaus
Elastic recoil after inspiratory muscles relax. Thoracic volume falls and pressure pushes air outward.
Kortti 112
Kysymys
What is the pleura?
Vastaus
A double membrane surrounding each lung. A thin fluid layer reduces friction during breathing.
Kortti 113
Kysymys
How is most oxygen transported in blood?
Vastaus
Bound to hemoglobin in red blood cells. Only a small amount dissolves directly in plasma.
Kortti 114
Kysymys
Why does carbon dioxide move from pulmonary blood into alveoli?
Vastaus
Its partial pressure is higher in incoming blood than in alveolar air. It diffuses down that gradient for exhalation.
Kortti 115
Kysymys
What helps keep swallowed material out of the airway?
Vastaus
The epiglottis and coordinated swallowing reflexes. The laryngeal opening is protected as food passes.
Kortti 116
Kysymys
How does the conducting airway remove trapped particles?
Vastaus
Mucus traps them, and cilia move the mucus toward the throat. This is the mucociliary escalator.
Kortti 117
Kysymys
In what form is most carbon dioxide transported in blood?
Vastaus
As bicarbonate ions. Red blood cells help convert carbon dioxide and water into bicarbonate.
Kortti 118
Kysymys
Which blood change is a strong normal stimulus to increase breathing?
Vastaus
A rise in carbon dioxide and the associated fall in pH. Brainstem centers adjust ventilation in response.
Kortti 119
Kysymys
Why must alveoli receive both air and blood?
Vastaus
Gas exchange needs ventilation and perfusion. Air without blood flow, or blood without airflow, cannot exchange gases effectively.
Kortti 120
Kysymys
Why does ventilation increase during exercise?
Vastaus
Active tissues use more oxygen and produce more carbon dioxide. Faster, deeper breathing helps meet that demand.
Kortti 121
Kysymys
What are the digestive system's core functions?
Vastaus
Ingestion, digestion, absorption, and elimination. Movement and secretion support those processes.
Kortti 122
Kysymys
What is the alimentary-canal sequence after the mouth?
Vastaus
Pharynx, esophagus, stomach, small intestine, large intestine, rectum, anus. Food passes through this continuous tube.
Kortti 123
Kysymys
What is mechanical digestion?
Vastaus
Physical breakdown and mixing of food without changing its molecules. Chewing and stomach churning are examples.
Kortti 124
Kysymys
What are two major functions of the stomach?
Vastaus
It stores and mixes food and begins substantial protein digestion. Acid denatures proteins, converts pepsinogen to pepsin, and provides the low pH pepsin needs.
Kortti 125
Kysymys
Where does most nutrient absorption occur?
Vastaus
The small intestine. Folds, villi, and microvilli create a large absorptive surface.
Kortti 126
Kysymys
Which nutrient does salivary amylase begin digesting in the mouth?
Vastaus
Carbohydrates, especially starch. Salivary amylase breaks starch into smaller carbohydrates.
Kortti 127
Kysymys
What is chemical digestion?
Vastaus
Enzymatic breakdown of large food molecules into absorbable units. Chemical bonds are changed during the process.
Kortti 128
Kysymys
What is peristalsis?
Vastaus
Wave-like smooth-muscle contractions that move material forward. It occurs throughout much of the digestive tract.
Kortti 129
Kysymys
What is a main function of the large intestine?
Vastaus
Absorbing water and electrolytes and forming feces. Resident microbes also process some undigested material.
Kortti 130
Kysymys
What digestive product does the liver make?
Vastaus
Bile. Bile salts help disperse dietary fat into smaller droplets.
Kortti 131
Kysymys
What does a digestive sphincter do?
Vastaus
It regulates movement between regions of the digestive tract. Circular muscle contracts to close a passage.
Kortti 132
Kysymys
What does the pancreas release into the small intestine?
Vastaus
Digestive enzymes and bicarbonate-rich fluid. Bicarbonate helps neutralize acidic material from the stomach.
Kortti 133
Kysymys
How do intestinal villi improve absorption?
Vastaus
They increase surface area. Each villus contains blood capillaries and a lymphatic lacteal for transported nutrients.
Kortti 134
Kysymys
What is the gallbladder's role?
Vastaus
It stores and concentrates bile. It releases bile into the small intestine when fatty food arrives.
Kortti 135
Kysymys
Which macronutrient's absorbed products usually enter intestinal lacteals before reaching the blood?
Vastaus
Most dietary lipids. Their absorbed products travel through lymph before entering the bloodstream.
Kortti 136
Kysymys
Which accessory organs help digestion without food passing through them?
Vastaus
The teeth, tongue, salivary glands, liver, gallbladder, and pancreas. Teeth and the tongue act mechanically; the other accessory organs add or store digestive secretions.
Kortti 137
Kysymys
What organs make up the urinary system?
Vastaus
The kidneys, ureters, urinary bladder, and urethra. Kidneys make urine; the remaining organs transport, store, and release it.
Kortti 138
Kysymys
What is a nephron?
Vastaus
The kidney's functional unit. It filters blood and adjusts the filtrate to form urine.
Kortti 139
Kysymys
Where does blood filtration begin in a nephron?
Vastaus
At the renal corpuscle. Pressure pushes water and small solutes from glomerular capillaries into the capsule.
Kortti 140
Kysymys
What moves urine from a kidney to the bladder?
Vastaus
A ureter. Smooth-muscle contractions propel urine along the tube.
Kortti 141
Kysymys
What is the urinary bladder's main role?
Vastaus
Temporary urine storage. Stretch receptors help trigger the urge to urinate as it fills.
Kortti 142
Kysymys
Which structure carries urine from the bladder out of the body?
Vastaus
The urethra. It is distinct from the ureters that enter the bladder.
Kortti 143
Kysymys
What is tubular reabsorption?
Vastaus
Movement of useful substances from nephron fluid back into blood. Water, glucose, and ions are common examples.
Kortti 144
Kysymys
What is the glomerulus?
Vastaus
A capillary tuft that filters blood in the renal corpuscle. Cells and most large proteins normally remain in circulation.
Kortti 145
Kysymys
How does more ADH change urine?
Vastaus
It makes urine more concentrated and lowers its volume. More water is reabsorbed from the collecting ducts.
Kortti 146
Kysymys
What path does filtrate follow after entering the glomerular capsule?
Vastaus
Proximal convoluted tubule → nephron loop → distal convoluted tubule → collecting duct. The collecting duct receives forming urine from multiple nephrons.
Kortti 147
Kysymys
What is tubular secretion?
Vastaus
Movement of selected substances from blood into nephron fluid. It helps eliminate wastes and regulate ions and pH.
Kortti 148
Kysymys
Besides removing waste, what does the urinary system regulate?
Vastaus
Water, electrolytes, acid-base balance, and blood volume. Kidney hormones also affect blood pressure and red-cell production.
Kortti 149
Kysymys
Why does dehydration usually reduce urine volume?
Vastaus
The body conserves water by increasing renal reabsorption. ADH is an important signal in this response.
Kortti 150
Kysymys
Why do the kidneys receive a large blood flow?
Vastaus
They must continuously filter plasma and regulate its composition. High flow supports waste removal and homeostasis.
Kortti 151
Kysymys
What is lymph?
Vastaus
Interstitial fluid that has entered lymphatic vessels. It eventually returns to the bloodstream.
Kortti 152
Kysymys
What is innate immunity?
Vastaus
Rapid, nonspecific defense present before a particular exposure. Barriers, inflammation, and several immune cells contribute.
Kortti 153
Kysymys
What is a major function of lymph nodes?
Vastaus
Filtering lymph and providing sites for immune-cell activation. Swelling can reflect an active immune response.
Kortti 154
Kysymys
What does the spleen filter?
Vastaus
Blood. It removes aged blood cells and supports immune responses to blood-borne antigens.
Kortti 155
Kysymys
What is a key function of B lymphocytes?
Vastaus
Producing antibody-secreting cells and memory cells. Antibodies bind specific antigens.
Kortti 156
Kysymys
What distinguishes adaptive immunity?
Vastaus
It targets specific antigens and develops memory. Later exposure can trigger a faster, stronger response.
Kortti 157
Kysymys
Which lymphatic organ is important for T-cell maturation?
Vastaus
The thymus. It is most active early in life.
Kortti 158
Kysymys
What is the body's first physical barrier against many pathogens?
Vastaus
Intact skin and mucous membranes. Their secretions and normal microbes add protection.
Kortti 159
Kysymys
What is a key function of T lymphocytes?
Vastaus
Coordinating immune responses or killing infected cells. Different T-cell types perform different roles.
Kortti 160
Kysymys
What does an antibody bind?
Vastaus
A specific antigen. Binding can neutralize a target or mark it for other immune defenses.
Kortti 161
Kysymys
What is the purpose of inflammation after tissue injury?
Vastaus
To contain damage, recruit defenses, and begin repair. Redness, heat, swelling, and pain can accompany it.
Kortti 162
Kysymys
Why is a second adaptive response often faster than the first?
Vastaus
Memory lymphocytes remain after the first exposure. They respond quickly when the same antigen appears again.
Kortti 163
Kysymys
What does a phagocyte do?
Vastaus
It engulfs particles, microbes, or debris. Neutrophils and macrophages are important examples.
Kortti 164
Kysymys
How does vaccination support adaptive immunity?
Vastaus
It safely exposes the immune system to antigen information. This promotes memory without requiring the full disease.
Kortti 165
Kysymys
Why is lymphatic fluid return important?
Vastaus
It prevents excess interstitial fluid from accumulating. Lymphatic vessels return fluid and leaked proteins to blood.
Kortti 166
Kysymys
What structures belong to the integumentary system?
Vastaus
Skin, hair, nails, sweat glands, and sebaceous glands. Together they form the body's outer covering.
Kortti 167
Kysymys
What is the epidermis?
Vastaus
The outer epithelial layer of skin. It is avascular and contains protective keratinized cells.
Kortti 168
Kysymys
How does sweating cool the body?
Vastaus
Evaporation removes heat from the skin. Skin blood-flow changes also help regulate heat loss.
Kortti 169
Kysymys
What is a major role of melanin in skin?
Vastaus
Absorbing some ultraviolet radiation. It also contributes to skin and hair color.
Kortti 170
Kysymys
How does skin contribute to sensation?
Vastaus
Sensory receptors detect touch, pressure, pain, and temperature. Nerves carry that information to the CNS.
Kortti 171
Kysymys
What is the dermis?
Vastaus
The connective-tissue layer beneath the epidermis. It contains vessels, nerves, glands, and hair follicles.
Kortti 172
Kysymys
How does skin support vitamin D production?
Vastaus
Ultraviolet light starts conversion of a skin molecule into a vitamin D precursor. The liver and kidneys complete activation.
Kortti 173
Kysymys
Why does a deep skin wound bleed but a shallow epidermal scrape may not?
Vastaus
Blood vessels are in the dermis, not the epidermis. A wound must reach vascular tissue to damage them.
Kortti 174
Kysymys
What is a gamete?
Vastaus
A haploid reproductive cell. Human sperm and oocytes each carry 23 chromosomes.
Kortti 175
Kysymys
What are the testes' two main reproductive functions?
Vastaus
Producing sperm and secreting testosterone. Sperm develop in seminiferous tubules.
Kortti 176
Kysymys
What tube carries sperm from the epididymis toward the ejaculatory duct?
Vastaus
The ductus, or vas, deferens. Smooth muscle propels sperm during ejaculation.
Kortti 177
Kysymys
What is ovulation?
Vastaus
Release of a secondary oocyte from an ovary. A surge in luteinizing hormone helps trigger it.
Kortti 178
Kysymys
Where does fertilization usually occur?
Vastaus
In a uterine tube. The early embryo then travels toward the uterus.
Kortti 179
Kysymys
What are the ovaries' two main reproductive functions?
Vastaus
Producing oocytes and secreting sex hormones. Estrogen and progesterone help regulate the reproductive cycle.
Kortti 180
Kysymys
What is the uterus' main reproductive role?
Vastaus
Supporting implantation and development of an embryo and fetus. Its muscular wall also contracts during birth.
Kortti 181
Kysymys
What causes menstruation when pregnancy does not occur?
Vastaus
Falling ovarian hormones allow the uterine lining to shed. A new cycle then begins.
Kortti 182
Kysymys
How does a sperm cell's structure support its function?
Vastaus
Its flagellum provides movement, and its head carries DNA plus enzymes used during fertilization. Mitochondria supply energy in the midpiece.
Kortti 183
Kysymys
What is the placenta's exchange role?
Vastaus
It allows gases, nutrients, and wastes to move between maternal and fetal circulations. Their blood normally does not mix directly.
Kortti 184
Kysymys
Why is meiosis necessary for sexual reproduction?
Vastaus
It halves chromosome number in gametes. Fertilization then restores the diploid number.
Kortti 185
Kysymys
How do sex hormones regulate reproductive control pathways?
Vastaus
They usually feed back on the hypothalamus and pituitary. This adjusts release of hormones that act on the gonads.
Kortti 186
Kysymys
What does cell theory state?
Vastaus
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.
Kortti 187
Kysymys
What is the defining structural feature of a prokaryotic cell?
Vastaus
It lacks a membrane-bound nucleus. Its DNA occupies a nucleoid region.
Kortti 188
Kysymys
What is the cell membrane's main role?
Vastaus
Regulating movement between the cell and its environment. Its phospholipid bilayer is selectively permeable.
Kortti 189
Kysymys
What is the nucleus' main role?
Vastaus
Storing most of a eukaryotic cell's DNA. Nuclear pores regulate exchange with the cytoplasm.
Kortti 190
Kysymys
Where are proteins assembled?
Vastaus
At ribosomes. Ribosomes may float in cytosol or attach to rough endoplasmic reticulum.
Kortti 191
Kysymys
What distinguishes a eukaryotic cell from a prokaryotic cell?
Vastaus
A eukaryotic cell has a membrane-bound nucleus and other membrane-bound organelles. Animals, plants, fungi, and protists are eukaryotes.
Kortti 192
Kysymys
What is a mitochondrion's main function?
Vastaus
Producing most cellular ATP through aerobic respiration. Its inner membrane provides a large reaction surface.
Kortti 193
Kysymys
What does rough endoplasmic reticulum mainly produce?
Vastaus
Proteins for secretion, membranes, or organelles. Ribosomes on its surface make the proteins.
Kortti 194
Kysymys
Which organelle carries out photosynthesis in plants and algae?
Vastaus
The chloroplast. It converts light energy into chemical energy stored in organic molecules.
Kortti 195
Kysymys
What does the Golgi apparatus do?
Vastaus
It modifies, sorts, and packages cell products. Vesicles carry those products to their destinations.
Kortti 196
Kysymys
What is a lysosome's role?
Vastaus
Digesting worn cell parts and engulfed material. Its enzymes work best in an acidic interior.
Kortti 197
Kysymys
What are major functions of smooth endoplasmic reticulum?
Vastaus
Lipid synthesis, detoxification, and calcium storage. Its membrane lacks attached ribosomes.
Kortti 198
Kysymys
What does the cytoskeleton provide?
Vastaus
Cell shape, internal organization, movement, and transport tracks. It is built from protein filaments.
Kortti 199
Kysymys
What is diffusion?
Vastaus
Net movement from higher to lower concentration. It is passive and continues until dynamic equilibrium is reached.
Kortti 200
Kysymys
What happens to an animal cell in a strongly hypotonic solution?
Vastaus
Water enters and the cell swells. Without a cell wall, it may burst.
Kortti 201
Kysymys
What happens during interphase?
Vastaus
The cell grows, performs normal functions, and copies its DNA. Interphase precedes mitotic division.
Kortti 202
Kysymys
What is the result of mitosis followed by cytokinesis?
Vastaus
Two genetically similar daughter cells. Chromosome number is normally preserved.
Kortti 203
Kysymys
What is osmosis?
Vastaus
Diffusion of water across a selectively permeable membrane. Water moves toward the side with more nonpenetrating solute.
Kortti 204
Kysymys
What happens to an animal cell in a hypertonic solution?
Vastaus
Water leaves and the cell shrinks. The external solution has a higher effective solute concentration.
Kortti 205
Kysymys
Why are cells generally small?
Vastaus
A high surface-area-to-volume ratio supports efficient exchange. Volume grows faster than surface area as a cell enlarges.
Kortti 206
Kysymys
What is cytokinesis?
Vastaus
Division of the cytoplasm. It separates one cell into two after nuclear division.
Kortti 207
Kysymys
How does active transport differ from passive transport?
Vastaus
It uses energy to move substances against a gradient. Passive transport moves down a gradient without direct energy input.
Kortti 208
Kysymys
What happens to an animal cell in an isotonic solution?
Vastaus
There is no net water movement. Water still crosses in both directions at equal rates.
Kortti 209
Kysymys
Which structures are typical of plant cells but not animal cells?
Vastaus
A cellulose cell wall, chloroplasts, and a large central vacuole. Both cell types have membranes, nuclei, and mitochondria.
Kortti 210
Kysymys
How do cells contribute to a multicellular organism's organization?
Vastaus
Specialized cells form tissues, tissues form organs, and organs form systems. Division of labor supports complex functions.
Kortti 211
Kysymys
What is DNA's primary biological role?
Vastaus
Storing hereditary information. Its nucleotide sequence contains instructions used to build functional RNA and proteins.
Kortti 212
Kysymys
What are the three parts of a DNA nucleotide?
Vastaus
A deoxyribose sugar, a phosphate group, and a nitrogenous base. Nucleotides link to form each strand.
Kortti 213
Kysymys
Which bases pair in double-stranded DNA?
Vastaus
Adenine with thymine, and cytosine with guanine. Hydrogen bonds hold complementary strands together.
Kortti 214
Kysymys
How does RNA differ from DNA?
Vastaus
RNA usually has ribose, uses uracil instead of thymine, and is usually single-stranded. Several RNA types help express genes.
Kortti 215
Kysymys
What is a gene?
Vastaus
A DNA sequence that contributes to a functional product. The product may be a protein or a functional RNA.
Kortti 216
Kysymys
What is a chromosome?
Vastaus
A long DNA molecule packaged with proteins. It contains many genes and other sequences.
Kortti 217
Kysymys
What is DNA replication?
Vastaus
Copying DNA before cell division. Each new DNA molecule contains one old strand and one newly made strand.
Kortti 218
Kysymys
What is the usual flow of information from a protein-coding gene?
Vastaus
DNA to RNA to protein. Transcription makes RNA; translation builds the polypeptide.
Kortti 219
Kysymys
What happens during transcription?
Vastaus
RNA is synthesized from a DNA template. For a protein-coding gene, that RNA functions as or is processed into messenger RNA.
Kortti 220
Kysymys
What does messenger RNA carry?
Vastaus
A copy of coding information from DNA to a ribosome. Its codons specify the amino-acid sequence.
Kortti 221
Kysymys
What is a codon?
Vastaus
A three-nucleotide sequence in mRNA. Most codons specify an amino acid; some signal start or stop.
Kortti 222
Kysymys
What is the usual role of the AUG codon?
Vastaus
It starts translation and specifies methionine. The ribosome uses it to establish the reading frame.
Kortti 223
Kysymys
What happens during translation?
Vastaus
A ribosome reads mRNA and joins amino acids into a polypeptide. Transfer RNAs match codons with amino acids.
446 korttia
ATI TEAS 7 Science Flashcards: A&P, Biology, Chemistry & Scientific Reasoning
Opiskele tätä pakkaa ilmaiseksiNibomo avautuu, jotta voit aloittaa opiskelun.
Kortti 224
Kysymys
What is transfer RNA's role in protein synthesis?
Vastaus
It carries an amino acid and matches its anticodon to an mRNA codon. This places the correct amino acid in sequence.
Kortti 225
Kysymys
What is an anticodon?
Vastaus
A three-base sequence on tRNA complementary to an mRNA codon. Pairing helps decode the message.
Kortti 226
Kysymys
What is a mutation?
Vastaus
A change in a DNA sequence. Its effect may be harmful, neutral, or beneficial depending on location and context.
Kortti 227
Kysymys
Why can a one-base insertion in a coding sequence have a large effect?
Vastaus
It can shift the reading frame. Every downstream codon may change until a stop signal appears.
Kortti 228
Kysymys
Why can changing one amino acid alter a protein's function?
Vastaus
Amino-acid sequence helps determine folding and shape. Shape controls many protein interactions.
Kortti 229
Kysymys
What is ribosomal RNA's role in protein synthesis?
Vastaus
It forms the structural and catalytic core of ribosomes. Ribosomal RNA helps align translation components and catalyzes peptide-bond formation.
Kortti 230
Kysymys
Why can different cell types contain the same DNA but perform different jobs?
Vastaus
They express different sets of genes. Different proteins give cells different structures and functions.
Kortti 231
Kysymys
Which mutation can be passed to offspring?
Vastaus
A mutation present in a gamete-forming lineage. A mutation limited to ordinary body cells is not inherited through reproduction.
Kortti 232
Kysymys
What is an allele?
Vastaus
An alternative version of a gene. Diploid individuals usually carry two alleles for each autosomal gene.
Kortti 233
Kysymys
What is genotype?
Vastaus
An organism's allele combination for a gene or set of genes. Genotype contributes to phenotype.
Kortti 234
Kysymys
What does homozygous mean?
Vastaus
Having two identical alleles for a gene. Examples include AA and aa.
Kortti 235
Kysymys
What makes an allele dominant in a simple Mendelian trait?
Vastaus
One copy is enough for its phenotype to appear in a heterozygote. Dominant does not mean common or beneficial.
Kortti 236
Kysymys
What does Mendel's law of segregation describe?
Vastaus
The two alleles for a gene separate during gamete formation. Each gamete receives one allele.
Kortti 237
Kysymys
What is phenotype?
Vastaus
An observable trait or characteristic. It can reflect genotype, environment, and their interaction.
Kortti 238
Kysymys
What does heterozygous mean?
Vastaus
Having two different alleles for a gene. An example is Aa.
Kortti 239
Kysymys
When does a recessive phenotype usually appear in a simple autosomal trait?
Vastaus
When both alleles are recessive. A heterozygote carries the allele without showing that phenotype.
Kortti 240
Kysymys
When does independent assortment apply most clearly?
Vastaus
When genes are on different chromosomes or far apart on the same chromosome. Their allele pairs enter gametes independently.
Kortti 241
Kysymys
What does a Punnett square predict?
Vastaus
Expected offspring genotype probabilities from specified parental gametes. It does not guarantee outcomes in a small family.
Kortti 242
Kysymys
For Aa × Aa, what is the chance of an aa offspring?
Vastaus
One fourth, or 25%. The genotype ratio is expected to be 1 AA : 2 Aa : 1 aa.
Kortti 243
Kysymys
For Aa × Aa with complete dominance, what phenotypic ratio is expected?
Vastaus
Three dominant-phenotype offspring to one recessive-phenotype offspring. This is a probability across many offspring.
Kortti 244
Kysymys
How can a test cross reveal the genotype behind a dominant phenotype?
Vastaus
Cross the individual with a homozygous recessive partner. Recessive offspring show that the unknown parent carried a recessive allele.
Kortti 245
Kysymys
What happens in incomplete dominance?
Vastaus
A heterozygote has an intermediate phenotype. Neither allele fully masks the other.
Kortti 246
Kysymys
How is the probability of two independent genetic events both occurring found?
Vastaus
Multiply their individual probabilities. This is the product rule.
Kortti 247
Kysymys
What does a pedigree show?
Vastaus
How a trait appears across generations of a family. Its pattern can suggest a mode of inheritance.
Kortti 248
Kysymys
Why can two parents have offspring ratios that differ from a Punnett-square expectation?
Vastaus
Each fertilization is a chance event. Expected ratios become more apparent with larger numbers of offspring.
Kortti 249
Kysymys
What happens in codominance?
Vastaus
Both alleles are distinctly expressed in a heterozygote. The AB blood type is a common example.
Kortti 250
Kysymys
What are major roles of carbohydrates?
Vastaus
Providing quick energy, storing energy, and forming some structures. Monosaccharides are their basic building blocks.
Kortti 251
Kysymys
What is a monomer?
Vastaus
A small building block that can join with others to form a larger molecule. Glucose, amino acids, and nucleotides are examples in different classes.
Kortti 252
Kysymys
What happens in a dehydration-synthesis reaction?
Vastaus
Monomers join while water is removed. The reaction builds a larger biological molecule.
Kortti 253
Kysymys
What does an enzyme do?
Vastaus
It lowers activation energy and speeds a reaction without being consumed. Its shape helps it bind specific substrates.
Kortti 254
Kysymys
What are major roles of lipids?
Vastaus
Long-term energy storage, membranes, insulation, and signaling. Lipids are mostly nonpolar and do not mix well with water.
Kortti 255
Kysymys
What does it mean for a protein to denature?
Vastaus
Its normal shape is disrupted. Heat, extreme pH, or chemicals can reduce its function.
Kortti 256
Kysymys
What happens during hydrolysis?
Vastaus
Water is used to split a larger molecule into smaller units. Digestion often uses hydrolysis reactions.
Kortti 257
Kysymys
Why do phospholipids form bilayers in water?
Vastaus
Their hydrophilic heads interact with water while hydrophobic tails turn inward. This arrangement forms cell-membrane structure.
Kortti 258
Kysymys
What are proteins built from?
Vastaus
Amino acids linked by peptide bonds. Their folded shapes support enzymes, transport, signaling, structure, and movement.
Kortti 259
Kysymys
How do starch and glycogen compare?
Vastaus
Both store glucose; plants use starch and animals use glycogen. Their branching patterns differ.
Kortti 260
Kysymys
How do saturated and unsaturated fatty acids differ?
Vastaus
Saturated fatty acids lack carbon-carbon double bonds; unsaturated ones have one or more. Double bonds often introduce bends.
Kortti 261
Kysymys
What immediate energy-carrying molecule powers many cell processes?
Vastaus
ATP. Energy released from nutrients can be transferred into ATP's phosphate bonds.
Kortti 262
Kysymys
What are nucleic acids built from?
Vastaus
Nucleotides. DNA stores hereditary information, while RNA performs several roles in gene expression.
Kortti 263
Kysymys
Which elements are common in all four major biological macromolecule classes?
Vastaus
Carbon, hydrogen, and oxygen. Nitrogen and phosphorus occur prominently in some classes.
Kortti 264
Kysymys
Why is three-dimensional shape important for macromolecules?
Vastaus
Shape determines many interactions and functions. A changed shape can prevent a molecule from binding its target.
Kortti 265
Kysymys
What are triglycerides built from?
Vastaus
One glycerol molecule and three fatty acids. They join through ester bonds to form a common energy-storage lipid.
Kortti 266
Kysymys
What is a pathogen?
Vastaus
An agent capable of causing disease. Not every microorganism is pathogenic.
Kortti 267
Kysymys
What type of cell is a bacterium?
Vastaus
A prokaryotic cell. Bacteria usually reproduce by binary fission.
Kortti 268
Kysymys
What cell type do fungi have?
Vastaus
Eukaryotic cells. Some fungi are unicellular yeasts, while others form multicellular filaments.
Kortti 269
Kysymys
What does disease transmission describe?
Vastaus
How an infectious agent moves to a susceptible host. Routes include contact, droplets, airborne spread, food, water, and vectors.
Kortti 270
Kysymys
What is a biological vector?
Vastaus
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.
Kortti 271
Kysymys
Why are viruses dependent on host cells?
Vastaus
They lack the complete machinery for reproduction and metabolism. They use host components to make new virus particles.
Kortti 272
Kysymys
What is a protist?
Vastaus
A diverse eukaryote that is not classified as an animal, plant, or fungus. Some protists cause disease, while many do not.
Kortti 273
Kysymys
Why do antibiotics not treat viral infections?
Vastaus
They target bacterial structures or processes that viruses lack. Antiviral drugs use different targets.
Kortti 274
Kysymys
How can normal microbiota protect a host?
Vastaus
They occupy space and use resources that pathogens might otherwise exploit. Some also support digestion or immune development.
Kortti 275
Kysymys
How does sterilization differ from disinfection?
Vastaus
Sterilization destroys or removes all microbial life, including resistant forms; disinfection reduces pathogens on objects. The required method depends on use.
Kortti 276
Kysymys
How do infection and disease differ?
Vastaus
Infection means an agent is established in a host; disease means normal function is impaired and signs or symptoms occur. Infection may be asymptomatic.
Kortti 277
Kysymys
How can breaking a transmission route reduce infectious disease?
Vastaus
It interrupts the chain connecting a source with a susceptible host. Hand hygiene, clean water, ventilation, and vector control target different links.
Kortti 278
Kysymys
What is an atom?
Vastaus
The smallest unit of an element that retains that element's chemical identity. Atoms contain a nucleus surrounded by electrons.
Kortti 279
Kysymys
What charge and location does an electron have?
Vastaus
Negative charge in the electron cloud around the nucleus. Electrons drive most chemical bonding.
Kortti 280
Kysymys
Why are valence electrons important?
Vastaus
They participate most directly in bonding and reactions. Their arrangement helps predict chemical behavior.
Kortti 281
Kysymys
What do elements in the same periodic-table group often share?
Vastaus
Similar valence-electron patterns and chemical properties. A group is a vertical column.
Kortti 282
Kysymys
What is an ion?
Vastaus
An atom or group of atoms with a net electric charge. Its total numbers of protons and electrons are unequal.
Kortti 283
Kysymys
What charge and location does a proton have?
Vastaus
Positive charge in the nucleus. The number of protons determines the element.
Kortti 284
Kysymys
What does an element's atomic number equal?
Vastaus
Its number of protons. A neutral atom has the same number of electrons.
Kortti 285
Kysymys
How does a neutral atom form a cation?
Vastaus
By losing one or more electrons. It has more protons than electrons and a positive charge.
Kortti 286
Kysymys
An atom has 8 protons. How many electrons does it have if it is neutral?
Vastaus
Eight electrons. Neutral atoms have equal positive and negative charges.
Kortti 287
Kysymys
What charge and location does a neutron have?
Vastaus
No electric charge, in the nucleus. Neutron number can vary among isotopes of an element.
Kortti 288
Kysymys
What does mass number equal?
Vastaus
Protons plus neutrons in one atom. It is a whole number for a specific isotope.
Kortti 289
Kysymys
How does a neutral atom form an anion?
Vastaus
By gaining one or more electrons. It has more electrons than protons and a negative charge.
Kortti 290
Kysymys
What does a period represent on the periodic table?
Vastaus
A horizontal row. Moving across a period changes proton number one element at a time.
Kortti 291
Kysymys
What are isotopes?
Vastaus
Atoms of the same element with different numbers of neutrons. They have the same atomic number but different mass numbers.
Kortti 292
Kysymys
What is matter?
Vastaus
Anything that has mass and occupies space. Solids, liquids, gases, and plasma are forms of matter.
Kortti 293
Kysymys
What distinguishes a solid from a liquid or gas?
Vastaus
A solid has a definite shape and volume. Its particles vibrate around relatively fixed positions.
Kortti 294
Kysymys
What is a physical change?
Vastaus
A change in form or state without changing chemical identity. Melting and cutting are examples.
Kortti 295
Kysymys
What is a physical property?
Vastaus
A characteristic observed without changing a substance's identity. Density, color, and melting point are examples.
Kortti 296
Kysymys
How does an element differ from a compound?
Vastaus
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.
Kortti 297
Kysymys
What distinguishes a liquid?
Vastaus
It has a definite volume but takes the shape of its container. Its particles remain close while moving past one another.
Kortti 298
Kysymys
What is a chemical change?
Vastaus
A process that forms one or more substances with new chemical identities. Bond rearrangement occurs.
Kortti 299
Kysymys
What is a chemical property?
Vastaus
A substance's ability to undergo a particular chemical change. Flammability and reactivity with acid are examples.
Kortti 300
Kysymys
Which phase changes connect solids and liquids?
Vastaus
Melting changes a solid to a liquid; freezing changes a liquid to a solid. These are opposite physical changes.
Kortti 301
Kysymys
How does a pure substance differ from a mixture?
Vastaus
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.
Kortti 302
Kysymys
What distinguishes a gas?
Vastaus
It has neither a definite shape nor a definite volume. It expands to fill its container.
Kortti 303
Kysymys
What is the formula for density?
Vastaus
Density = mass ÷ volume. Density is an intensive property.
Kortti 304
Kysymys
Which phase changes connect liquids and gases?
Vastaus
Vaporization changes a liquid to a gas; condensation changes a gas to a liquid. Evaporation is vaporization at a liquid's surface.
Kortti 305
Kysymys
What is a mixture?
Vastaus
Two or more substances physically combined in variable proportions. Its components retain their chemical identities.
Kortti 306
Kysymys
How do intensive and extensive properties differ?
Vastaus
Intensive properties do not depend on sample amount; extensive properties do. Density and temperature are intensive, while mass and volume are extensive.
Kortti 307
Kysymys
A 20 g sample occupies 5 mL. What is its density?
Vastaus
4 g/mL. Divide 20 g by 5 mL.
Kortti 308
Kysymys
Which phase changes connect solids and gases directly?
Vastaus
Sublimation changes a solid to a gas; deposition changes a gas to a solid. Neither transition passes through the liquid state.
Kortti 309
Kysymys
How do homogeneous and heterogeneous mixtures differ?
Vastaus
A homogeneous mixture is uniform throughout; a heterogeneous mixture is not. A solution is homogeneous.
Kortti 310
Kysymys
Where are reactants and products written in a chemical equation?
Vastaus
Reactants are on the left; products are on the right. The arrow shows the direction represented.
Kortti 311
Kysymys
Why must a chemical equation be balanced?
Vastaus
Atoms are conserved in ordinary chemical reactions. Each element must have the same atom count on both sides.
Kortti 312
Kysymys
What does a coefficient in a chemical equation change?
Vastaus
The number of whole particles or moles represented. It multiplies every atom in the following formula.
Kortti 313
Kysymys
Why should subscripts not be changed when balancing an equation?
Vastaus
Changing a subscript changes the substance's identity. Balancing changes coefficients only.
Kortti 314
Kysymys
What coefficients balance H₂ + O₂ → H₂O?
Vastaus
2, 1, 2: 2H₂ + O₂ → 2H₂O. Both sides then contain four hydrogen atoms and two oxygen atoms.
Kortti 315
Kysymys
What pattern defines a synthesis reaction?
Vastaus
Two or more reactants form a more complex product. A general pattern is A + B → AB.
Kortti 316
Kysymys
What are typical products when a hydrocarbon burns completely in oxygen?
Vastaus
Carbon dioxide and water. Incomplete combustion can produce carbon monoxide or carbon.
Kortti 317
Kysymys
What is the net ionic equation for a typical strong acid–strong base neutralization?
Vastaus
H⁺(aq) + OH⁻(aq) → H₂O(l). The remaining ions are spectators and do not appear in the net ionic equation.
Kortti 318
Kysymys
What is a precipitate?
Vastaus
An insoluble solid that forms from substances in solution. Its appearance can signal a chemical reaction.
Kortti 319
Kysymys
What pattern defines a decomposition reaction?
Vastaus
One compound breaks into simpler products. A general pattern is AB → A + B.
Kortti 320
Kysymys
What is an exothermic reaction?
Vastaus
A reaction that releases heat to the surroundings. The surroundings often warm.
Kortti 321
Kysymys
What occurs in an oxidation-reduction reaction?
Vastaus
Electrons transfer or atoms change oxidation state. Oxidation is electron loss; reduction is electron gain.
Kortti 322
Kysymys
What is activation energy?
Vastaus
The minimum energy barrier reactants must overcome to react. Catalysts lower this barrier.
Kortti 323
Kysymys
Which observations can provide evidence of a chemical reaction?
Vastaus
Gas formation, a precipitate, sustained color change, light, or temperature change. No single sign proves a reaction without context.
Kortti 324
Kysymys
What is an endothermic reaction?
Vastaus
A reaction that absorbs heat from the surroundings. The surroundings may cool.
Kortti 325
Kysymys
Why does raising temperature usually speed a reaction?
Vastaus
Particles collide more often and with greater energy. More collisions overcome activation energy.
Kortti 326
Kysymys
Why can higher reactant concentration increase reaction rate?
Vastaus
More reactant particles occupy a given volume. This raises collision frequency.
Kortti 327
Kysymys
Why does powdered solid often react faster than one large piece?
Vastaus
Powder exposes more surface area. More particles are available for collisions.
Kortti 328
Kysymys
How does a catalyst speed a reaction?
Vastaus
It provides a pathway with lower activation energy. The catalyst is regenerated rather than consumed overall.
Kortti 329
Kysymys
How can increasing pressure affect a reaction between gases?
Vastaus
It can increase rate by bringing gas particles closer together. Collision frequency rises when volume falls.
Kortti 330
Kysymys
What does a reaction inhibitor do?
Vastaus
It slows a reaction. It may block a pathway, interfere with a catalyst, or remove reactive intermediates.
Kortti 331
Kysymys
Why can very high temperature slow an enzyme-catalyzed reaction?
Vastaus
The enzyme can denature and lose its active shape. Moderate warming helps only within the enzyme's stable range.
Kortti 332
Kysymys
What is dynamic equilibrium?
Vastaus
Forward and reverse reactions continue at equal rates. Concentrations remain constant even though particles still react.
Kortti 333
Kysymys
Does a catalyst change the final equilibrium amounts?
Vastaus
No. It speeds forward and reverse reactions, so equilibrium is reached sooner without changing its position.
Kortti 334
Kysymys
At equilibrium, what usually happens when the concentration of a dissolved or gaseous reactant increases?
Vastaus
The system shifts toward consuming some added reactant. It forms more product until a new equilibrium is reached.
Kortti 335
Kysymys
What is a solution?
Vastaus
A homogeneous mixture. Its components are uniformly distributed at the molecular or ionic level.
Kortti 336
Kysymys
How do solute and solvent differ?
Vastaus
The solute is dissolved; the solvent is the dissolving medium. The solvent is often present in greater amount.
Kortti 337
Kysymys
What does aqueous mean in chemistry?
Vastaus
Dissolved in water. The symbol
(aq)marks an aqueous species in an equation.Kortti 338
Kysymys
What does concentration describe?
Vastaus
The amount of solute in a given amount of solution or solvent. Different units express it in different ways.
Kortti 339
Kysymys
What is molarity?
Vastaus
Moles of solute per liter of solution. Its unit is mol/L, written M.
Kortti 340
Kysymys
What is the molarity of 0.50 mol solute in 2.0 L of solution?
Vastaus
0.25 M. Divide 0.50 mol by 2.0 L.
Kortti 341
Kysymys
What stays constant when water is added to dilute a solution without reaction?
Vastaus
The moles of solute. Volume increases and concentration decreases.
Kortti 342
Kysymys
Which equation relates concentration and volume before and after a dilution?
Vastaus
M₁V₁ = M₂V₂. It follows from conserving the amount of solute.
Kortti 343
Kysymys
What is solubility?
Vastaus
The maximum concentration of a solute that can be achieved in a solution at equilibrium under specified conditions. Temperature and the substances involved matter.
Kortti 344
Kysymys
What is a saturated solution?
Vastaus
A solution holding the maximum dissolved solute at those conditions. Extra solute remains undissolved at equilibrium.
Kortti 345
Kysymys
What is an electrolyte?
Vastaus
A substance that produces mobile ions in solution and conducts electricity. Soluble ionic compounds are common examples.
Kortti 346
Kysymys
What does 'like dissolves like' predict?
Vastaus
Substances with similar polarity tend to mix well. Polar solvents favor polar or ionic solutes; nonpolar solvents favor nonpolar solutes.
Kortti 347
Kysymys
Does heating always increase solubility?
Vastaus
No. Many solids become more soluble in water, but gases usually become less soluble as temperature rises.
Kortti 348
Kysymys
What is an unsaturated solution?
Vastaus
A solution that can dissolve more solute at the stated conditions. It is below the solubility limit.
Kortti 349
Kysymys
What does a Brønsted-Lowry acid donate?
Vastaus
A proton, H⁺. In water, acid behavior increases hydronium-ion concentration.
Kortti 350
Kysymys
What does pH describe?
Vastaus
The hydronium-ion concentration on a logarithmic scale. Lower pH means higher hydronium concentration.
Kortti 351
Kysymys
At 25 °C, what pH range is acidic?
Vastaus
Below 7. A neutral aqueous solution is pH 7 at this temperature.
Kortti 352
Kysymys
How does hydronium concentration change when pH drops by 1 unit?
Vastaus
It increases tenfold. The pH scale is logarithmic.
Kortti 353
Kysymys
What does a Brønsted-Lowry base accept?
Vastaus
A proton, H⁺. Many bases in water also increase hydroxide-ion concentration.
Kortti 354
Kysymys
At 25 °C, what is the relationship between pH and pOH?
Vastaus
pH + pOH = 14. pOH is the negative base-10 logarithm of hydroxide-ion concentration; this relation applies to aqueous solutions at 25 °C.
Kortti 355
Kysymys
At 25 °C, what pH range is basic?
Vastaus
Above 7. Basic solutions have less hydronium and more hydroxide than neutral water.
Kortti 356
Kysymys
What are typical products of a strong acid reacting with a strong base?
Vastaus
Water and an ionic salt. Hydrogen ions and hydroxide ions combine to form water.
Kortti 357
Kysymys
What does strong mean for an acid or base?
Vastaus
It produces its characteristic ions essentially completely in water. Strong acids ionize; soluble ionic strong bases dissociate. Strength is separate from concentration.
Kortti 358
Kysymys
What does a buffer do?
Vastaus
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⁻.
Kortti 359
Kysymys
How does an acid-base indicator work?
Vastaus
Its color depends on pH. The change occurs over a characteristic pH range.
Kortti 360
Kysymys
A solution has pH 9 at 25 °C. What is its pOH?
Vastaus
5. Subtract the pH from 14.
Kortti 361
Kysymys
How does a concentrated weak acid differ from a dilute strong acid?
Vastaus
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.
Kortti 362
Kysymys
What is the SI base unit of length?
Vastaus
The meter (m). Centimeters and millimeters are decimal subdivisions of a meter.
Kortti 363
Kysymys
Which tool directly measures mass in a laboratory?
Vastaus
A balance. A spring scale measures force, often reported as weight.
Kortti 364
Kysymys
What is the SI base unit of mass?
Vastaus
The kilogram (kg). Laboratory mass is also commonly reported in grams.
Kortti 365
Kysymys
A student needs to measure about 35 mL of liquid and can choose a beaker or graduated cylinder. Which should they use?
Vastaus
A graduated cylinder. Read the scale at eye level.
Kortti 366
Kysymys
What is the SI base unit of time?
Vastaus
The second (s). Minutes and hours are accepted for many everyday uses.
Kortti 367
Kysymys
Where should the volume of a clear water-based liquid be read in a graduated cylinder?
Vastaus
At the bottom of the meniscus. Keep your eye level with the liquid surface.
Kortti 368
Kysymys
What is the SI base unit of thermodynamic temperature?
Vastaus
The kelvin (K). Degrees Celsius are widely used for laboratory and body temperatures.
Kortti 369
Kysymys
Which tool measures temperature?
Vastaus
A thermometer. Its range and resolution should match the task.
Kortti 370
Kysymys
What factor does the metric prefix kilo- represent?
Vastaus
One thousand, or 10³. One kilometer equals 1,000 meters.
Kortti 371
Kysymys
A ruler's smallest marking is 1 mm. To what place should a careful analog reading usually be estimated?
Vastaus
One place beyond the smallest marking, when the scale allows it. The final digit is uncertain.
Kortti 372
Kysymys
What is measurement accuracy?
Vastaus
Closeness to an accepted or true value. A systematic error can make precise measurements inaccurate.
Kortti 373
Kysymys
How do mass and weight differ?
Vastaus
Mass is the amount of matter; weight is gravitational force on that mass. Mass stays constant when gravity changes, but weight does not.
Kortti 374
Kysymys
What factor does the metric prefix milli- represent?
Vastaus
One thousandth, or 10⁻³. One milliliter is 0.001 liter.
Kortti 375
Kysymys
How can the volume of an irregular solid be measured with water?
Vastaus
Use water displacement. Subtract the initial water volume from the final volume after submerging the object.
Kortti 376
Kysymys
What is measurement precision?
Vastaus
Closeness of repeated measurements to one another. Precise results can still be consistently wrong.
Kortti 377
Kysymys
What is an instrument's resolution?
Vastaus
The smallest change it can meaningfully display or distinguish. Higher resolution does not automatically guarantee accuracy.
Kortti 378
Kysymys
How many centimeters are in 2.5 meters?
Vastaus
2.5 × 10² cm (250 cm). Multiply meters by the exact conversion factor 100 cm/m.
Kortti 379
Kysymys
Why must a numerical measurement include a unit?
Vastaus
The unit identifies the quantity's scale. A bare number is ambiguous and cannot be compared reliably.
Kortti 380
Kysymys
What is a scientific observation?
Vastaus
Information recorded with senses or instruments. It should be distinguished from an explanation of what was observed.
Kortti 381
Kysymys
What makes a hypothesis scientifically useful?
Vastaus
It is testable and falsifiable. Evidence must be able to count against it.
Kortti 382
Kysymys
What is a scientific theory?
Vastaus
A broad, well-supported explanation of natural phenomena. It is not a casual guess and can be revised with new evidence.
Kortti 383
Kysymys
Which claim is falsifiable: 'No possible observation could count against this treatment's effectiveness' or 'This treatment lowers mean temperature within one hour'?
Vastaus
The claim that the treatment lowers mean temperature within one hour. An observation could count against it, so evidence can test it.
Kortti 384
Kysymys
What is an inference?
Vastaus
A logical interpretation based on observations and prior knowledge. It goes beyond the raw measurement.
Kortti 385
Kysymys
How does a prediction relate to a hypothesis?
Vastaus
It states an expected result if the hypothesis is correct. Experiments compare observed results with that expectation.
Kortti 386
Kysymys
How does a scientific law differ from a scientific theory?
Vastaus
A law describes a consistent pattern; a theory explains how or why patterns occur. One does not mature into the other.
Kortti 387
Kysymys
What does reliability mean for a measurement or procedure?
Vastaus
It produces consistent results under the same conditions. Repetition helps assess reliability.
Kortti 388
Kysymys
What does a correlation show?
Vastaus
Two variables change together in a patterned way. Correlation alone does not establish that one causes the other.
Kortti 389
Kysymys
What is bias in scientific work?
Vastaus
A systematic influence that pushes observations, selection, or interpretation in one direction. Good design tries to prevent or measure it.
Kortti 390
Kysymys
What is the purpose of scientific peer review?
Vastaus
Independent experts evaluate methods, reasoning, and reporting before publication. It improves scrutiny but does not guarantee truth.
Kortti 391
Kysymys
What does validity ask about a study or measurement?
Vastaus
Whether it measures or tests what it claims to measure or test. Consistency alone does not ensure validity.
Kortti 392
Kysymys
What evidence most strengthens a causal claim?
Vastaus
A well-controlled experiment that manipulates the suspected cause. Random assignment reduces confounding, while independent replication tests whether the result holds with new data.
Kortti 393
Kysymys
What is a primary scientific source?
Vastaus
A report of original methods, data, and results. A review article synthesizes many primary studies.
Kortti 394
Kysymys
How should an unexpected outlier be handled?
Vastaus
Investigate and report it rather than deleting it automatically. Exclusion needs a documented scientific reason.
Kortti 395
Kysymys
What is a confounding variable?
Vastaus
An outside factor related to both the suspected cause and the outcome. It can create a misleading association.
Kortti 396
Kysymys
Why should a sample represent the population of interest?
Vastaus
Results generalize poorly when important groups are missing or overrepresented. Sampling method matters as much as size.
Kortti 397
Kysymys
What is a scientific model?
Vastaus
A simplified representation used to explain or predict a system. A model is useful within its assumptions and limits.
Kortti 398
Kysymys
Why should measurements report uncertainty or reasonable precision?
Vastaus
Every measurement has limits. Reporting more digits than the method supports creates false precision.
Kortti 399
Kysymys
If results match a prediction once, what is the safest conclusion?
Vastaus
The results support the hypothesis under those conditions. One result does not prove the hypothesis in every setting.
Kortti 400
Kysymys
What is a direct relationship between two variables?
Vastaus
As one increases, the other tends to increase; as one decreases, the other tends to decrease. The relationship need not be perfectly linear.
Kortti 401
Kysymys
Which variable is usually placed on the x-axis of an experimental graph?
Vastaus
The independent variable. It is the factor selected or changed by the investigator.
Kortti 402
Kysymys
What does the slope of a straight-line graph represent?
Vastaus
Change in y divided by change in x. It is the response rate per unit change in the other variable.
Kortti 403
Kysymys
A line rises 12 units in y while x rises 3 units. What is its slope?
Vastaus
4 units of y per unit of x. Divide 12 by 3.
Kortti 404
Kysymys
What is an inverse relationship?
Vastaus
As one variable increases, the other tends to decrease. Their product is constant only in a strictly inverse proportion.
Kortti 405
Kysymys
Which variable is usually placed on the y-axis of an experimental graph?
Vastaus
The dependent variable. It is the measured response.
Kortti 406
Kysymys
What does a plateau on a response graph indicate?
Vastaus
The measured response has stopped changing much despite further x increases. A limiting factor may have been reached.
Kortti 407
Kysymys
What is interpolation?
Vastaus
Estimating a value within the range of measured data. It is generally safer than extrapolating beyond that range.
Kortti 408
Kysymys
What pattern suggests no relationship between two plotted variables?
Vastaus
The response shows no consistent change as the other variable changes. Points may scatter without a trend.
Kortti 409
Kysymys
Before comparing values in a data table, what should you check?
Vastaus
Headings, units, and conditions. Numbers from different measures or scales cannot be compared directly.
Kortti 410
Kysymys
If 3 samples require 12 mL total, how much is needed for 5 equal samples?
Vastaus
20 mL. The rate is 4 mL per sample, so multiply by 5.
Kortti 411
Kysymys
How is the arithmetic mean calculated?
Vastaus
Add all values and divide by the number of values. A large outlier can shift the mean.
Kortti 412
Kysymys
Why is extrapolation uncertain?
Vastaus
It assumes the observed trend continues outside measured conditions. The relationship may change beyond the data range.
Kortti 413
Kysymys
A culture grows from 20 to 50 cells in 6 hours. What is the average growth rate?
Vastaus
5 cells per hour. The change is 30 cells divided by 6 hours.
Kortti 414
Kysymys
A measurement rises from 40 to 50. What is the percent increase?
Vastaus
25%. The increase is 10, and 10 ÷ 40 × 100 = 25%.
Kortti 415
Kysymys
When can the median describe a typical value better than the mean?
Vastaus
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.
Kortti 416
Kysymys
How do quantitative and qualitative data differ?
Vastaus
Quantitative data are numerical; qualitative data describe categories or qualities. Both can answer scientific questions.
Kortti 417
Kysymys
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?
Vastaus
6. The observed rate is 2 response units per dose unit, so interpolation at dose 3 gives 6.
Kortti 418
Kysymys
How can a graph reveal a nonlinear relationship?
Vastaus
The points follow a curve rather than a straight line. The rate of change varies across the x-range.
Kortti 419
Kysymys
What is the range of a data set?
Vastaus
Maximum minus minimum. It describes total spread but ignores the distribution between the endpoints.
Kortti 420
Kysymys
What makes a scientific research question testable?
Vastaus
It identifies measurable variables or observable outcomes. The needed data must be obtainable.
Kortti 421
Kysymys
In an experiment, what is the independent variable?
Vastaus
The factor deliberately changed or assigned by the investigator. In a simple one-factor experiment, changing one independent variable helps isolate its effect.
Kortti 422
Kysymys
What should a hypothesis connect?
Vastaus
A proposed explanation with a measurable outcome. It should lead to a prediction that evidence can challenge.
Kortti 423
Kysymys
What is a controlled variable, or constant?
Vastaus
A condition kept the same across groups. Holding it constant prevents it from explaining outcome differences.
Kortti 424
Kysymys
What is the purpose of a control group?
Vastaus
It provides a comparison without the experimental treatment. Differences can then be attributed more confidently to the treatment.
Kortti 425
Kysymys
In an experiment, what is the dependent variable?
Vastaus
The measured response. It may change because of the independent variable.
Kortti 426
Kysymys
What form can a useful experimental prediction take?
Vastaus
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.
Kortti 427
Kysymys
What does a positive control demonstrate?
Vastaus
That the setup can produce a known response. If it fails, the test system may be defective.
Kortti 428
Kysymys
Why randomly assign subjects to experimental groups?
Vastaus
To distribute known and unknown differences more evenly. This reduces selection bias and confounding.
Kortti 429
Kysymys
How can blinding reduce bias?
Vastaus
It keeps participants, observers, or both unaware of treatment assignments. Expectations are less likely to affect behavior or measurement.
Kortti 430
Kysymys
What is a placebo?
Vastaus
An inactive treatment designed to resemble the experimental treatment. It helps separate treatment effects from expectation effects.
Kortti 431
Kysymys
What does a negative control demonstrate?
Vastaus
What happens when the tested cause is absent. An unexpected response may reveal contamination or another source.
Kortti 432
Kysymys
Why does a larger sample often improve a study?
Vastaus
It reduces the influence of chance variation and supports more stable estimates. It cannot repair a biased sampling method.
Kortti 433
Kysymys
Why repeat trials within an experiment?
Vastaus
To estimate variability and check consistency. One unusual trial then has less influence.
Kortti 434
Kysymys
Why must an experimental procedure be detailed and standardized?
Vastaus
So groups are treated consistently and others can reproduce the work. Uncontrolled procedural differences create alternative explanations.
Kortti 435
Kysymys
Why calibrate a measuring instrument before collecting data?
Vastaus
To compare its readings with a known standard and reduce systematic error. Calibration improves confidence in accuracy.
Kortti 436
Kysymys
What is an operational definition?
Vastaus
A precise statement of how a variable is measured or manipulated. It turns an abstract concept into a repeatable procedure.
Kortti 437
Kysymys
How does independent replication differ from repeated trials?
Vastaus
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.
Kortti 438
Kysymys
Why should raw data be recorded before interpretation?
Vastaus
It preserves the observations separately from conclusions. Others can check calculations and reasoning.
Kortti 439
Kysymys
What should a scientific conclusion do?
Vastaus
Answer the research question using the data and acknowledge limits. It should not claim more than the design supports.
Kortti 440
Kysymys
What should happen when data do not support a hypothesis?
Vastaus
Revise or reject the hypothesis and consider new tests. Data should not be altered to preserve the original idea.
Kortti 441
Kysymys
What is a study limitation?
Vastaus
A feature that restricts interpretation or generalization. Small samples, short duration, and imperfect measurements are examples.
Kortti 442
Kysymys
Why are ethics part of experimental design?
Vastaus
Research must protect participants, organisms, and communities while balancing risks and benefits. Consent and humane treatment are key examples.
Kortti 443
Kysymys
How does an observational study differ from an experiment?
Vastaus
It measures variables without assigning the exposure. It can find associations but usually supports weaker causal conclusions.
Kortti 444
Kysymys
Plants receive 0, 2, or 4 hours of added light, and growth is measured. What is the independent variable?
Vastaus
Hours of added light. Plant growth is the dependent variable.
Kortti 445
Kysymys
A fertilizer study gives every plant the same water, soil, and temperature. What are these conditions?
Vastaus
Controlled variables. Keeping them constant isolates the fertilizer's effect.
Kortti 446
Kysymys
A drug group improves more than a control group, but the groups were not randomly assigned. What is the main caution?
Vastaus
Preexisting group differences could explain some improvement. The result is suggestive, but the design weakens a causal claim.
446 korttia
ATI TEAS 7 Science Flashcards: A&P, Biology, Chemistry & Scientific Reasoning
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