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