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