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