Title: PLTW HBS — Human Anatomy & Physiology
Tags: Course::HBS HBS_Unit3 HBS_Unit1 HBS_Unit2 HBS_Unit4 cloze

Front: What is standard anatomical position?
Back: Body erect, facing forward, feet together, arms at sides with palms facing forward.
Why: All directional terms are defined relative to it.

Front: Why is anatomical position the standardized reference for directional terms?
Back: So terms like 'anterior' mean the same thing regardless of how the body is actually positioned, preventing miscommunication.

Front: Superior vs inferior?
Back: Superior = toward the head/upper body; inferior = toward the feet/lower body.

Front: Anterior (ventral) vs posterior (dorsal)?
Back: Anterior = toward the front; posterior = toward the back.

Front: Medial vs lateral?
Back: Medial = toward the body's midline; lateral = away from the midline.

Front: Proximal vs distal?
Back: Proximal = closer to the trunk/point of attachment; distal = farther from it (used for limbs).

Front: Superficial vs deep?
Back: Superficial = toward the body surface; deep = farther beneath the surface.

Front: What does the sagittal plane divide?
Back: The body into left and right portions (a vertical plane).

Front: What does the frontal (coronal) plane divide?
Back: The body into anterior (front) and posterior (back) portions.

Front: What does the transverse plane divide?
Back: The body into superior (upper) and inferior (lower) portions (a horizontal/cross-section).
Why: Imaging like CT 'slices' are transverse.

Front: Dorsal vs ventral body cavity?
Back: Dorsal (back) = cranial + vertebral cavities (brain, spinal cord); ventral (front) = thoracic + abdominopelvic cavities.

Front: What separates the thoracic and abdominopelvic cavities?
Back: The diaphragm.

Front: What is homeostasis?
Back: The maintenance of a stable internal environment despite changes outside the body.
Why: Trunk concept for every HBS unit.

Front: What does the root osteo- mean?
Back: Bone (e.g., osteocyte, osteoporosis).
Why: Word-part decoding is heavily tested (MEDTERM 22%).

Front: What does the root my/o- mean?
Back: Muscle (e.g., myocardium, myology).

Front: What does the root arthr/o- mean?
Back: Joint (e.g., arthritis, arthroplasty).

Front: What does the root chondr/o- mean?
Back: Cartilage (e.g., chondrocyte).

Front: What does the root cardi/o- mean?
Back: Heart (e.g., cardiology, myocardium).

Front: What does the suffix -itis mean?
Back: Inflammation (e.g., arthritis = joint inflammation).

Front: What does the suffix -ology mean?
Back: The study of (e.g., osteology = the study of bone).

Front: What does the suffix -ectomy mean?
Back: Surgical removal (e.g., appendectomy).

Front: What does the suffix -plasty mean?
Back: Surgical repair/reshaping (e.g., arthroplasty).

Front: What does the suffix -algia mean?
Back: Pain (e.g., myalgia = muscle pain).

Front: Prefixes hyper- vs hypo-?
Back: Hyper- = above/excessive; hypo- = below/deficient (e.g., hypertension vs hypotension).

Front: Decode the term 'arthritis' from its parts.
Back: Arthr/o (joint) + -itis (inflammation) = inflammation of a joint.
Why: Shows the decode strategy, not just memorized words.

Front: Build the term for 'muscle pain' from word parts.
Back: My/o (muscle) + -algia (pain) = myalgia.

Front: Name the four primary tissue types.
Back: Epithelial, connective, muscle, and nervous tissue.

Front: What is the general function of epithelial tissue?
Back: To cover, line, and protect surfaces and form glands; it controls what enters/leaves the body.

Front: Bone and blood are examples of which tissue type?
Back: Connective tissue (it supports, connects, and transports; has cells in an extracellular matrix).

Front: List the major functions of the skeletal system.
Back: Support, protection of organs, movement (with muscles), mineral storage (calcium), and blood cell production (hematopoiesis).

Front: Why is it wrong to think of bone as a dry, non-living structure?
Back: Bone is living connective tissue with cells, a blood supply, and constant remodeling by osteoblasts and osteoclasts.

Front: Compact vs spongy bone?
Back: Compact (cortical) bone is dense and forms the hard outer layer; spongy (trabecular) bone is porous, lighter, and houses marrow.

Front: Osteoblasts vs osteoclasts?
Back: Osteoblasts BUILD bone (deposit matrix); osteoclasts BREAK DOWN bone (resorb matrix).

Front: What is an osteocyte?
Back: A mature bone cell embedded in the matrix that maintains bone tissue.

Front: How does bone remodeling maintain bone health?
Back: Osteoclasts resorb old/damaged bone and osteoblasts deposit new bone; the balance adapts bone to stress and regulates blood calcium.
Why: Links structure to homeostasis.

Front: Name the shaft and the ends of a long bone.
Back: Diaphysis = the shaft; epiphysis = each end.

Front: What is the periosteum?
Back: The tough connective-tissue membrane covering the outer bone surface; site of attachment and bone growth/repair.

Front: What is found in the medullary cavity of a long bone?
Back: In adults, yellow (fatty) marrow. Red marrow (blood-cell production) is found in spongy bone and in the cavities of children, not the adult medullary cavity.

Front: What does the epiphyseal (growth) plate do?
Back: It is cartilage that allows lengthwise bone growth in children; it ossifies (closes) when growth ends.

Front: Axial vs appendicular skeleton?
Back: Axial = skull, vertebral column, rib cage (central axis); appendicular = limbs and their girdles (shoulders, hips).

Front: Name the three structural joint categories.
Back: Fibrous (immovable, e.g., skull sutures), cartilaginous (slightly movable), and synovial (freely movable).

Front: Flexion vs extension?
Back: Flexion decreases the angle of a joint; extension increases it (straightening).

Front: Abduction vs adduction?
Back: Abduction moves a limb away from the midline; adduction moves it toward the midline.

Front: Tendon vs ligament?
Back: A tendon connects muscle to bone; a ligament connects bone to bone.

Front: What is the role of cartilage at a synovial joint?
Back: It cushions the bone ends and reduces friction during movement.

Front: Simple (closed) vs compound (open) fracture?
Back: Simple = bone breaks but does not pierce the skin; compound = broken bone breaks through the skin (higher infection risk).

Front: Why does inadequate calcium or vitamin D weaken bones over time?
Back: Calcium is the mineral that hardens bone and vitamin D is needed to absorb it; deficiency reduces deposition, lowering bone density (osteoporosis risk).

Front: Why does weight-bearing exercise strengthen bones?
Back: Mechanical stress signals osteoblasts to deposit more bone, increasing density (bone adapts to load).
Why: Wolff's law application.

Front: Name the three muscle tissue types.
Back: Skeletal, cardiac, and smooth muscle.

Front: Compare skeletal, cardiac, and smooth muscle on striation and control.
Back: Skeletal = striated, voluntary; cardiac = striated, involuntary; smooth = non-striated, involuntary.

Front: What unique structure connects cardiac muscle cells for coordinated contraction?
Back: Intercalated discs (with gap junctions).

Front: What is a sarcomere?
Back: The basic contractile unit of skeletal muscle, bounded by two Z-lines.
Why: Trunk structure for the contraction mechanism.

Front: Actin vs myosin filaments?
Back: Actin = thin filaments; myosin = thick filaments with heads that form cross-bridges.

Front: State the sliding filament theory of contraction.
Back: Myosin heads bind actin and pull the thin filaments toward the sarcomere center, shortening the sarcomere; the filaments themselves don't shorten.
Why: High-yield mechanism.

Front: What is the role of ATP in the cross-bridge cycle?
Back: ATP detaches the myosin head from actin and, once hydrolyzed, re-cocks it for the next power stroke; no ATP means no detachment (rigor).

Front: What triggers contraction once calcium is released?
Back: Ca2+ binds troponin, moving tropomyosin off actin's binding sites so myosin can attach and pull.

Front: What happens at the neuromuscular junction to start contraction?
Back: A motor neuron releases acetylcholine, which depolarizes the muscle fiber, triggering Ca2+ release and contraction.
Why: Links to cell signaling.

Front: What is a motor unit?
Back: One motor neuron and all the muscle fibers it controls.

Front: Origin vs insertion of a muscle?
Back: Origin = attachment on the more stationary bone; insertion = attachment on the bone that moves.

Front: Agonist vs antagonist muscles (with an example)?
Back: Agonist (prime mover) produces the movement; antagonist opposes/relaxes (e.g., biceps flexes, triceps extends the elbow).

Front: Why is it wrong to say muscles can push bones?
Back: Muscles only generate force by pulling (contracting); they cannot push, which is why antagonistic pairs are needed to move a joint both ways.

Front: Why must skeletal muscles work in antagonistic pairs?
Back: Because a muscle can only pull, an opposing muscle is required to move the joint back the other way.

Front: Aerobic vs anaerobic energy use in muscle?
Back: Aerobic (with O2) yields much more ATP for sustained effort; anaerobic (without enough O2) is fast but produces lactic acid and tires quickly.

Front: What is oxygen debt (EPOC)?
Back: The extra oxygen needed after exercise to clear lactic acid and restore ATP/creatine phosphate stores.

Front: What causes muscle fatigue during sustained contraction?
Back: Depletion of ATP/energy stores and accumulation of metabolites (e.g., from anaerobic metabolism) reduce the muscle's ability to contract.
Why: Connects to EMG fatigue data.

Front: In a lever system, what are the fulcrum, effort, and load in the body?
Back: Fulcrum = the joint; effort = muscle force; load = the weight/resistance moved.

Front: Why can a small muscle force sometimes move a larger load?
Back: A lever with the right arrangement provides mechanical advantage, trading distance/speed for force.

Front: What does an EMG (electromyography) measure?
Back: The electrical activity produced by muscle fibers during contraction.
Why: EBS is 18% of 072040.

Front: What does range of motion (ROM) measure, and with what tool?
Back: The angular distance a joint can move; measured with a goniometer.

Front: On an EMG, why does the signal often change as a muscle fatigues?
Back: Fatigue alters motor-unit firing; the EMG amplitude/frequency shifts, indicating reduced contractile capacity.

Front: EMG shows the biceps active during flexion and the triceps active during extension. What does this confirm?
Back: That the muscles act as an antagonistic pair, each driving opposite movements at the elbow.

Front: In a grip-fatigue experiment, name one variable you must hold constant.
Back: Examples: the same hand, posture, sensor placement, rest interval, and instructions for each trial.
Why: Experimental-control practice for EBS labs.

Front: A fatigue curve shows force declining over repeated trials. What is the dependent variable?
Back: The measured muscle force/output (what changes in response to repeated effort over time).

Front: Why measure ROM before and after a rehabilitation program?
Back: To quantify improvement (or limitation) in joint movement and judge whether the intervention worked.

Front: What is the goal of physical rehabilitation?
Back: To restore function, strength, and range of motion after injury or impairment.

Front: What does RICE stand for in acute injury care?
Back: Rest, Ice, Compression, Elevation.

Front: Why might a clinician choose an assistive device for a patient?
Back: To support function, reduce load on an injured structure, and enable safe movement during recovery.

Front: How does knowing muscle origin/insertion help design a rehab exercise?
Back: It tells you which movement a muscle produces, so you can target the correct muscle to restore that motion.
Why: Structure-to-function transfer.

Front: Why does immobilization for too long harm muscle and bone?
Back: Without load, muscle atrophies and bone loses density (use it or lose it), so controlled movement is reintroduced early.

Front: Why wear appropriate PPE in an HBS lab?
Back: To protect against chemical, biological, and physical hazards (eyes, skin, inhalation).

Front: Difference between a control and a constant (controlled variable)?
Back: A control is a comparison standard; constants are kept the same across groups so they don't confound results.

Front: Independent vs dependent variable?
Back: Independent = what you change; dependent = what you measure in response.

Front: Accuracy vs precision?
Back: Accuracy = closeness to the true value; precision = consistency of repeated measurements.

Front: Two group means have large overlapping error bars. What does that suggest?
Back: The difference may not be reliable; you need a statistical test before claiming an effect.

Front: Why does a larger sample size strengthen conclusions?
Back: It reduces the influence of random variation/outliers, giving a more reliable estimate.

Front: Why doesn't correlation prove causation in physiology data?
Back: A third variable or coincidence could explain the link; causation needs a controlled experiment.

Front: What are the three parts of a CER response?
Back: Claim, Evidence (specific data), and Reasoning (the science linking evidence to claim).

Front: An item asks you to 'relate structure to function' for a bone or muscle. What must your answer do?
Back: Describe the specific structure AND explain how that structure enables its function (not just name the part).
Why: Core HBS reasoning move.

Front: How does 'explain' differ from 'identify'?
Back: 'Identify' = name briefly; 'explain' = give the how/why mechanism.

Front: What does a 'predict' prompt require beyond the outcome?
Back: The predicted result PLUS the physiological reasoning for why it occurs.

Front: Strategy: how do you tackle an unfamiliar medical term on a test?
Back: Break it into prefix + root + suffix and translate each part (e.g., osteo+arthr+itis).
Why: Leverages MEDTERM word-part cards.

Front: Why is it wrong to assume a bigger muscle is always a stronger muscle?
Back: Force depends on cross-sectional area, fiber type, motor-unit recruitment, and leverage, not size alone, so size does not guarantee strength.

Front: Why is it wrong to read a larger EMG signal as always meaning a stronger contraction?
Back: EMG reflects electrical activity/recruitment, which correlates with effort but is also affected by fatigue, electrode placement, and technique, so amplitude does not equal force exactly.

Front: How does muscle contraction connect to cellular respiration (AP Bio)?
Back: Contraction consumes ATP made by cellular respiration; sustained activity needs aerobic respiration, and oxygen shortfall forces anaerobic metabolism (lactic acid).
Why: Bridges HBS to AP Bio energetics.

Front: How does bone remodeling illustrate homeostasis?
Back: Osteoblast/osteoclast balance keeps bone strong and stabilizes blood calcium, a regulated steady state responding to load and hormones.

Front: How does the sarcomere show structure-determines-function at the protein level?
Back: Actin and myosin's shapes let myosin heads bind and pull actin; the organized filament arrangement is what makes coordinated shortening possible.
Why: Bridges to AP Bio protein structure.

Front: How does the neuromuscular junction connect to cell signaling (AP Bio)?
Back: It is reception-transduction-response: ACh (ligand) binds receptors, triggering depolarization and Ca2+ release that causes the response (contraction).

Front: How do levers connect anatomy to physics/biomechanics?
Back: Joints act as fulcrums and muscles as effort; lever class and arm lengths determine the force vs speed/range tradeoff of a movement.

Front: A patient cannot extend the elbow but can still flex it. Which muscle of the antagonistic pair is most likely impaired, and why?
Back: The triceps (the extensor). Flexion is intact (biceps works), but loss of extension points to the muscle that straightens the joint, the triceps.
Why: Forces use of the agonist/antagonist model.

Front: An EMG trace shows steady amplitude that falls and shifts to lower frequency over 60 seconds of sustained grip. What is happening in the muscle?
Back: Fatigue: as ATP/energy stores deplete and metabolites build up, motor-unit firing changes, lowering force capacity, which the EMG amplitude/frequency shift reflects.
Why: Interpret-the-data move.

Front: A child's X-ray shows open epiphyseal plates while an adult's are closed. What does this predict about each one's remaining bone growth?
Back: The child can still grow in length (cartilage at the plate is active); the adult cannot, because the plates have ossified and lengthwise growth has stopped.
Why: Apply growth-plate structure to a prediction.

Front: After a leg cast is removed, the limb's muscle is visibly smaller and the bone is less dense. Explain why immobilization caused both changes.
Back: Without mechanical load, muscle atrophies and osteoblast activity drops so bone loses density (use-it-or-lose-it); load is needed to maintain both tissues.

Front: A sprinter feels a burning, tiring sensation in the legs late in a 400 m race. Which energy pathway dominates and what byproduct explains the burn?
Back: Anaerobic metabolism is dominating because O2 supply lags demand; it produces lactic acid quickly but limited ATP, contributing to fatigue.

Front: Two patients have equal calcium intake, but one does weight-bearing exercise and one is sedentary. Predict whose bone density is higher and justify.
Back: The exerciser's. Mechanical stress signals osteoblasts to deposit more bone (Wolff's law), so loading raises density beyond intake alone.

Q: The [...] theory says [...] heads pull [...] filaments toward the center of the sarcomere, shortening it.
A: sliding filament; myosin; actin

Q: [...] build bone while [...] break it down.
A: Osteoblasts; osteoclasts

Q: The three anatomical planes are [...] (left/right), [...] (front/back), and [...] (top/bottom).
A: sagittal; frontal; transverse

Q: A [...] connects muscle to bone; a [...] connects bone to bone.
A: tendon; ligament

Muscle contraction requires ATP and calcium ions, and calcium works by moving tropomyosin off actin's binding sites.

Q: An [...] measures the electrical activity of muscle; a [...] measures range of motion.
A: EMG; goniometer

Q: Skeletal muscles can only [...], so they work in [...] pairs to move a joint both ways.
A: pull; antagonistic

Front: What does the root neur/o- mean?
Back: Nerve (e.g., neuron, neurology, neuralgia).
Why: Word-part decoding is heavily tested (MEDTERM 22%).

Front: What does the root encephal/o- mean?
Back: Brain (e.g., encephalitis, electroencephalogram).

Front: What does the root myel/o- mean (nervous-system context)?
Back: Spinal cord (also marrow); e.g., myelitis (spinal cord) / myeloma (marrow).

Front: What does the root cerebr/o- mean?
Back: Cerebrum/brain (e.g., cerebral, cerebrovascular).

Front: What does the suffix -esthesia mean?
Back: Sensation/feeling (e.g., anesthesia = without sensation).

Front: What does the prefix dys- mean?
Back: Bad, painful, or difficult (e.g., dysfunction, dysphagia).

Front: What does the root endo- mean and -crine refer to in 'endocrine'?
Back: Endo- = within/inside; -crine = to secrete; endocrine glands secrete hormones internally into the blood.

Front: What does the root aden/o- mean?
Back: Gland (e.g., adenoma, adenopathy).

Front: What does the root gluc/o- (glyc/o-) mean?
Back: Sugar/glucose (e.g., glycogen, hyperglycemia).

Front: What does the suffix -emia mean?
Back: A blood condition (e.g., hyperglycemia = high blood sugar).

Front: Prefixes endo- vs exo-?
Back: Endo- = within (endocrine secretes into blood); exo- = outside (exocrine secretes through a duct).

Front: Decode 'encephalitis' from its parts.
Back: Encephal/o (brain) + -itis (inflammation) = inflammation of the brain.
Why: Shows decode strategy, not memorized words.

Front: Decode 'neuralgia' from its parts.
Back: Neur/o (nerve) + -algia (pain) = nerve pain.

Front: Build the term for 'high blood sugar' from word parts.
Back: Hyper- (excess) + glyc/o (sugar) + -emia (blood condition) = hyperglycemia.

Front: What does the root tox/o- mean?
Back: Poison/toxin (e.g., toxicology, toxicity).

Front: Name the three main functional parts of a neuron.
Back: Dendrites (receive signals), cell body/soma (integrates), and axon (sends the signal).

Front: Why does the long axon shape suit a neuron's function?
Back: Its length lets the signal travel from one body region to a distant target quickly along a single cell.
Why: Structure-to-function move.

Front: What is the resting membrane potential of a neuron?
Back: A charge difference (about -70 mV) where the inside is negative relative to the outside, ready to fire.

Front: What is an action potential?
Back: A rapid, all-or-none reversal of membrane charge (depolarization then repolarization) that travels down the axon as the nerve impulse.

Front: Why is the action potential described as 'all-or-none'?
Back: Once threshold is reached the impulse fires at full strength; below threshold it does not fire at all, so intensity is coded by frequency, not size.

Front: What ions move to depolarize a neuron during an action potential?
Back: Sodium (Na+) rushes in, making the inside more positive.

Front: What is a synapse?
Back: The junction between a neuron and its target where a signal is passed, usually by chemical neurotransmitters across a gap.

Front: At a chemical synapse, what are the four steps in order from action potential arrival to a change in the next cell?
Back: (1) The impulse triggers Ca2+ entry into the presynaptic terminal; (2) neurotransmitter is released into the cleft; (3) it binds receptors on the postsynaptic cell; (4) that changes the postsynaptic membrane potential.
Why: High-yield mechanism.

Front: Name a neurotransmitter and one of its roles.
Back: Acetylcholine (muscle activation), dopamine (reward/movement), or serotonin (mood) - any correct pairing.

Front: Why is it wrong to picture a nerve impulse jumping cell-to-cell like an electric wire across the synapse?
Back: Within a neuron the signal is electrical, but at most synapses it converts to a chemical messenger (neurotransmitter) that crosses the gap, so it is not a continuous electrical wire.

Front: What is the myelin sheath?
Back: A fatty insulating layer around many axons that speeds impulse conduction.

Front: How does myelin speed up conduction?
Back: The impulse jumps between gaps (nodes of Ranvier) in saltatory conduction instead of traveling continuously, so it moves faster.

Front: Why does losing myelin (e.g., in multiple sclerosis) impair function?
Back: Without insulation, impulses slow or fail, disrupting signaling to muscles and sensory pathways.
Why: Links structure damage to symptoms.

Front: Central vs peripheral nervous system?
Back: CNS = brain and spinal cord (integration/control); PNS = all nerves outside the CNS (carry signals to/from the body).

Front: Sensory (afferent) vs motor (efferent) neurons?
Back: Sensory carry signals TOWARD the CNS; motor carry commands AWAY from the CNS to muscles/glands.

Front: Somatic vs autonomic nervous system?
Back: Somatic controls voluntary skeletal muscle; autonomic controls involuntary functions (heart, glands, smooth muscle).

Front: Sympathetic vs parasympathetic divisions?
Back: Sympathetic = 'fight or flight' (speeds heart, dilates pupils); parasympathetic = 'rest and digest' (slows heart, aids digestion).

Front: What is the main function of the cerebrum?
Back: Higher-order processing: thought, voluntary movement, sensation, and language.

Front: What is the main function of the cerebellum?
Back: Coordination, balance, and fine motor control.

Front: What does the brainstem (incl. medulla) control?
Back: Vital involuntary functions such as heart rate, breathing, and blood pressure.

Front: What is the role of the hypothalamus?
Back: It links the nervous and endocrine systems and regulates homeostasis (temperature, hunger, hormone release).
Why: Bridges Unit 2's two systems.

Front: A patient has poor balance and clumsy movements but normal thinking. Which brain region is likely affected?
Back: The cerebellum, which coordinates balance and fine motor control.
Why: Structure-function diagnosis.

Front: Damage to the medulla is life-threatening. Why?
Back: It controls automatic vital functions like breathing and heart rate.

Front: List the five components of a reflex arc in order.
Back: Receptor, sensory (afferent) neuron, integration center, motor (efferent) neuron, effector.

Front: Receptor vs effector in a reflex arc?
Back: A receptor detects the stimulus; an effector (muscle or gland) carries out the response.

Front: Why is a reflex faster than a voluntary response?
Back: A reflex is integrated in the spinal cord and can act before the signal reaches the brain, removing processing delay.

Front: What is a stimulus and what is a response?
Back: A stimulus is a detectable change/input; a response is the body's reaction to it.

Front: Why does the knee-jerk reflex protect the body?
Back: It quickly adjusts muscle length to prevent overstretching/injury without waiting for conscious control.

Front: What does a reaction-time test measure?
Back: The time between a stimulus and the subject's voluntary motor response.
Why: EBS is 18% of 072040.

Front: In a ruler-drop test, the catch distance increases. What does that indicate about reaction time?
Back: A longer fall distance means a slower reaction time (more time elapsed before the catch).

Front: Name one variable you must hold constant in a reaction-time experiment.
Back: Examples: same hand, same starting distance, same instructions, same level of distraction across trials.
Why: Experimental-control practice.

Front: A class plots reaction time before vs after caffeine. What is the independent variable?
Back: The caffeine condition (what the experimenter changes); reaction time is the dependent variable.

Front: Why might reaction time vary between voluntary and reflex tasks?
Back: Voluntary responses route through the brain (slower); reflexes route through the spinal cord (faster).

Front: How can a drug change signaling at a synapse?
Back: It can mimic a neurotransmitter, block receptors, or prevent neurotransmitter breakdown/reuptake, altering the next cell's response.

Front: Agonist vs antagonist drug at a receptor?
Back: An agonist activates the receptor (mimics the neurotransmitter); an antagonist blocks it (prevents the response).

Front: Why do depressants slow reaction time?
Back: They reduce nervous-system excitability/signaling, delaying impulse transmission and motor response.

Front: Why would a reuptake inhibitor increase a neurotransmitter's effect?
Back: Blocking reuptake leaves more neurotransmitter in the cleft longer, prolonging receptor activation.

Front: What is a hormone?
Back: A chemical messenger secreted by an endocrine gland into the blood that acts on specific target cells.

Front: How do the nervous and endocrine systems differ in speed and duration?
Back: Nervous signals are fast and brief; hormonal signals are slower to start but longer-lasting.
Why: Core compare/contrast for Unit 2.

Front: Why does a hormone only affect certain 'target' cells?
Back: Only cells with the matching receptor for that hormone can respond to it.
Why: Specificity = receptor logic.

Front: Endocrine vs exocrine glands?
Back: Endocrine glands secrete hormones into the blood (ductless); exocrine glands secrete products through ducts (e.g., sweat, saliva).

Front: What hormone does the thyroid produce and what does it regulate?
Back: Thyroid hormone (e.g., thyroxine), which regulates metabolic rate.

Front: Why is the pituitary called the 'master gland'?
Back: Its hormones control several other endocrine glands.

Front: Which gland releases insulin and glucagon?
Back: The pancreas (islet cells).

Front: What hormone does the adrenal gland release in stress, and what is one effect?
Back: Epinephrine (adrenaline); it raises heart rate and mobilizes energy ('fight or flight').

Front: What is a negative feedback loop?
Back: A control system where a change triggers a response that reverses the change, returning the body toward a set point.
Why: Trunk concept for homeostasis.

Front: Negative vs positive feedback?
Back: Negative feedback opposes/reverses a change (most homeostasis); positive feedback amplifies a change (e.g., childbirth, clotting).

Front: Trace negative feedback control of body temperature when you get too hot.
Back: Sensors detect rising temperature, the control center signals sweating/vasodilation, heat is lost, and temperature returns to set point.

Front: A feedback graph oscillates around a set point. What does that pattern show?
Back: Negative feedback continuously correcting deviations to keep the variable near its set point.

Front: What does insulin do when blood glucose is high?
Back: It signals cells to take up glucose and the liver to store it as glycogen, lowering blood sugar.
Why: High-yield mechanism.

Front: What does glucagon do when blood glucose is low?
Back: It signals the liver to break down glycogen and release glucose, raising blood sugar.

Front: Insulin vs glucagon - opposing roles?
Back: Insulin lowers blood glucose; glucagon raises it. Together they keep blood sugar in range (antagonistic pair).

Front: Why does insulin deficiency (Type 1 diabetes) cause high blood glucose?
Back: Without insulin, cells cannot take up glucose efficiently, so it builds up in the blood (hyperglycemia).

Front: After a sugary meal, predict which hormone rises and the result.
Back: Insulin rises, driving glucose into cells and storage, lowering blood sugar back toward the set point.
Why: Predict-with-reasoning move.

Front: Why is it wrong to treat glucagon and glycogen as the same thing?
Back: Glucagon is the hormone that raises blood sugar; glycogen is the stored form of glucose in the liver/muscle, so one is a signal and the other is a storage molecule.

Front: What is a model organism?
Back: A non-human species studied to understand biology that often applies to humans (e.g., C. elegans, mice).

Front: Why is C. elegans useful for studying the nervous system?
Back: It is small, transparent, fast-breeding, and has a fully mapped, simple nervous system, making neural studies tractable.

Front: Why is it wrong to assume results from a model organism always transfer exactly to humans?
Back: Findings from model organisms guide human research but must be validated in humans because species differ in genetics and physiology.

Front: What is an assay?
Back: A standardized procedure to measure the presence, amount, or activity of something (e.g., a biological response).

Front: Positive control vs negative control?
Back: A positive control should give a known response (confirms the assay works); a negative control should give no response (confirms specificity/no contamination).

Front: Why does adequate sample size matter in a model-organism study?
Back: Larger samples reduce the impact of random variation and individual outliers, giving more reliable, generalizable results.

Front: Why replicate trials instead of running an experiment once?
Back: Replication tests reproducibility and reveals variability, strengthening confidence in the result.

Front: A study has no control group. What is the main weakness?
Back: There is no baseline to compare against, so any change cannot be attributed to the treatment.

Front: What is toxicology?
Back: The study of how chemicals/poisons harm living organisms, including dose and effect.

Front: Why are heavy metals (e.g., lead, mercury) harmful to the nervous system?
Back: They disrupt enzymes and signaling and can damage neurons, impairing nervous-system function.

Front: According to 'the dose makes the poison,' what determines whether a substance is harmful?
Back: The amount/exposure (dose): even helpful or normally safe substances can be toxic at a high enough dose, and toxins can be tolerable at very low doses.

Front: What makes a hypothesis testable?
Back: It is a specific, falsifiable prediction that an experiment can support or refute.

Front: Hypothesis vs conclusion?
Back: A hypothesis is a proposed, testable explanation before the experiment; a conclusion is the evidence-based judgment after analyzing data.

Front: A dose-response graph shows effect rising with concentration. What does the trend suggest?
Back: A dose-dependent relationship: increasing exposure increases the measured effect.

Front: Two groups' means differ but error bars overlap heavily. What should you conclude?
Back: The difference may not be reliable; a statistical test is needed before claiming an effect.

Front: Why state the limitations of an investigation?
Back: Limitations show what the data can and cannot support and guide more valid future experiments.

Front: Name one common limitation to report in a small classroom toxicology study.
Back: Examples: small sample size, short timeframe, measurement error, or limited dose range.

Front: Why doesn't a correlation between exposure and symptoms prove the chemical caused them?
Back: Other variables or coincidence could explain the link; causation requires a controlled experiment.

Front: An item asks you to 'relate structure to function' for a neuron. What must your answer do?
Back: Describe the specific structure AND explain how it enables the function (not just name the part).
Why: Core HBS reasoning move.

Front: A prompt says 'explain how negative feedback regulates blood glucose.' What must you include?
Back: The stimulus, sensor/control center, the corrective response (insulin or glucagon), and return to set point.

Front: What does a 'predict' endocrine prompt require beyond the outcome?
Back: The predicted hormone change/result PLUS the physiological reasoning for why it occurs.

Front: Strategy: how do you tackle an unfamiliar nervous/endocrine term on a test?
Back: Break it into prefix + root + suffix and translate each part (e.g., hyper+glyc+emia).
Why: Leverages MEDTERM word-part cards.

Front: How do the nervous and endocrine systems work together at the hypothalamus?
Back: The hypothalamus receives neural input and controls the pituitary's hormone release, linking fast neural signals to slower hormonal control.
Why: Bridges Unit 2's two systems.

Front: How is the synapse an example of cell signaling (AP Bio)?
Back: It is reception-transduction-response: a neurotransmitter (ligand) binds receptors, triggering a change in the target cell.
Why: Bridges HBS to AP Bio signaling.

Front: How does hormone-receptor specificity parallel enzyme-substrate specificity?
Back: Both rely on complementary shapes: only a matching molecule binds and triggers the effect, so structure determines function.

Front: How does negative feedback connect endocrine control to homeostasis broadly?
Back: Feedback loops continuously correct deviations (glucose, temperature, hormones), maintaining the stable internal environment that defines homeostasis.

Front: How does the reflex arc show division of labor in the nervous system?
Back: Sensory neurons input, the spinal cord integrates, and motor neurons output to effectors - a fast, distributed pathway separate from conscious brain control.

Front: A patient has slurred speech and poor balance but normal thinking and memory. Which brain region is most likely affected, and why?
Back: The cerebellum, which coordinates balance and fine motor control; intact cognition points away from the cerebrum.
Why: Localize-the-lesion reasoning.

Front: A toxin blocks voltage-gated sodium channels on axons. Predict the effect on action potentials and explain.
Back: Action potentials cannot fire or propagate, because Na+ influx is what depolarizes the membrane to threshold; signaling to muscles/sensation fails.
Why: Predict from mechanism.

Front: A fasting patient's blood glucose is low. Predict which pancreatic hormone rises and trace how it restores glucose.
Back: Glucagon rises; it signals the liver to break down glycogen and release glucose into the blood, raising it back toward the set point.
Why: Trace a feedback response.

Front: A person with an underactive thyroid reports fatigue, weight gain, and cold intolerance. Explain how low thyroid hormone produces these symptoms.
Back: Thyroid hormone sets metabolic rate; too little slows metabolism and heat production, causing low energy, weight gain, and feeling cold.
Why: Link hormone level to symptoms.

Front: In a ruler-drop test, a student's catch distance increases after staying up all night. Interpret what this says about reaction time and why.
Back: A longer catch distance means a slower reaction time; sleep deprivation reduces nervous-system processing speed, delaying the voluntary response.
Why: Interpret experimental data.

Front: A drug blocks the reuptake of a neurotransmitter at the synapse. Predict the effect on the postsynaptic cell and justify.
Back: The neurotransmitter stays in the cleft longer, so receptors are activated more/longer, amplifying the postsynaptic response.
Why: Predict drug effect on signaling.

Q: An [...] is an all-or-none reversal of membrane charge in which [...] (Na+) ions rush in to depolarize the axon.
A: action potential; sodium

Q: At a chemical synapse the impulse triggers [...] entry, releasing [...] that crosses the cleft and binds [...] on the next cell.
A: calcium; neurotransmitter; receptors

Q: The [...] sheath speeds conduction by letting the impulse jump between gaps in [...] conduction.
A: myelin; saltatory

Q: [...] lowers blood glucose by signaling cells to store it as [...], while [...] raises blood glucose by breaking glycogen down.
A: Insulin; glycogen; glucagon

Q: [...] feedback reverses a change toward a set point, while [...] feedback amplifies a change (e.g., childbirth).
A: Negative; positive

Q: [...] (afferent) neurons carry signals toward the CNS; [...] (efferent) neurons carry commands away from the CNS.
A: Sensory; motor

Q: A reflex arc runs receptor -> [...] -> [...] -> [...] -> effector.
A: sensory neuron; integration center; motor neuron

Front: What does the root angi/o- (vas/o-) mean?
Back: Vessel (e.g., angiogram, vasoconstriction).
Why: Word-part decoding is heavily tested (MEDTERM 22%).

Front: What does the root hem/o- (hemat/o-) mean?
Back: Blood (e.g., hemoglobin, hematology).

Front: Prefixes tachy- vs brady-?
Back: Tachy- = fast (tachycardia = fast heart rate); brady- = slow (bradycardia = slow heart rate).

Front: What does the root pulmon/o- mean?
Back: Lung (e.g., pulmonary, cardiopulmonary).

Front: What does the root pneum/o- (pneumon/o-) mean?
Back: Lung or air (e.g., pneumonia, pneumothorax).

Front: What does the suffix -pnea mean?
Back: Breathing (e.g., apnea = no breathing, dyspnea = difficult breathing).

Front: What does the root ox/o- (ox/i-) refer to?
Back: Oxygen (e.g., hypoxia, oximeter, oxygenation).

Front: What does the root immun/o- mean?
Back: Protection/immune (e.g., immunology, immunization).

Front: What does the root lymph/o- mean?
Back: Lymph/lymphatic (e.g., lymphocyte, lymphoma).

Front: What does the suffix -cyte mean?
Back: Cell (e.g., lymphocyte, erythrocyte).

Front: Decode 'tachycardia' from its parts.
Back: Tachy- (fast) + cardi/o (heart) + -ia (condition) = fast heart rate.
Why: Shows decode strategy.

Front: Decode 'dyspnea' from its parts.
Back: Dys- (difficult) + -pnea (breathing) = difficult/labored breathing.

Front: Decode 'lymphocyte' from its parts.
Back: Lymph/o (lymph) + -cyte (cell) = a lymph/immune cell.

Front: Name the four chambers of the heart.
Back: Right atrium, right ventricle, left atrium, left ventricle.

Front: Why is the left ventricle's wall thicker than the right's?
Back: It must generate higher pressure to pump blood through the entire systemic circuit (the body); the right only pumps to the lungs.
Why: Structure-to-function move.

Front: Trace blood flow through the heart starting at the right atrium.
Back: Right atrium -> right ventricle -> lungs (pulmonary) -> left atrium -> left ventricle -> body (aorta).
Why: High-yield pathway.

Front: Pulmonary vs systemic circulation?
Back: Pulmonary carries blood between the heart and lungs; systemic carries blood between the heart and the rest of the body.

Front: What is the function of heart valves?
Back: They keep blood flowing in one direction and prevent backflow between chambers/vessels.

Front: Why is it wrong to say arteries always carry oxygen-rich blood and veins always carry oxygen-poor blood?
Back: Arteries carry blood AWAY from the heart and veins carry it back, regardless of oxygen content: the pulmonary artery carries oxygen-poor blood and the pulmonary veins carry oxygen-rich blood.

Front: Arteries vs veins (structure and function)?
Back: Arteries carry blood away from the heart under high pressure (thick, elastic walls); veins return blood to the heart under low pressure (thinner walls, have valves).

Front: Why are capillary walls only one cell thick?
Back: The thin wall allows efficient diffusion of gases, nutrients, and wastes between blood and tissues.

Front: Why do veins need valves but arteries generally don't?
Back: Venous pressure is low, so valves prevent backflow as blood returns to the heart against gravity; arterial pressure is high enough to maintain forward flow.

Front: What is the cardiac cycle?
Back: One complete heartbeat: the sequence of atrial and ventricular contraction (systole) and relaxation (diastole).

Front: Systole vs diastole?
Back: Systole = contraction (pumping blood out); diastole = relaxation (chambers fill).

Front: What is blood pressure expressed as, and what do the numbers mean?
Back: Systolic/diastolic (e.g., 120/80): pressure during ventricular contraction over pressure during relaxation.

Front: What does an EKG/ECG measure?
Back: The electrical activity of the heart over time.
Why: EBS is 18% of 072040.

Front: On an EKG, what does the QRS complex represent?
Back: Ventricular depolarization (the ventricles contracting).

Front: An EKG shows a very high beat frequency with normal-shaped waves. What does this indicate?
Back: Tachycardia - a fast heart rate.

Front: How do you estimate heart rate from an EKG strip?
Back: Count the beats (R-waves) over a known time interval and convert to beats per minute.

Front: Trace the path of air from the nose to the gas-exchange site.
Back: Nose/mouth -> pharynx -> larynx -> trachea -> bronchi -> bronchioles -> alveoli.

Front: What is the alveolus and what happens there?
Back: A tiny air sac in the lungs where O2 enters the blood and CO2 leaves it by diffusion.

Front: Why are alveoli small, numerous, and thin-walled?
Back: They maximize surface area and minimize diffusion distance for efficient gas exchange.
Why: Structure-to-function move.

Front: Which way do O2 and CO2 diffuse at the alveolus?
Back: O2 diffuses from alveolar air into blood; CO2 diffuses from blood into the alveolus - each moves down its concentration gradient.

Front: Why does damage to alveoli (e.g., emphysema) reduce oxygen uptake?
Back: It destroys surface area for diffusion, so less O2 can enter the blood per breath.

Front: How does the diaphragm drive inhalation?
Back: It contracts and flattens, increasing chest volume and lowering pressure so air flows in.

Front: What does spirometry measure?
Back: Lung volumes and airflow during breathing.

Front: What is tidal volume?
Back: The volume of air moved in or out in a normal, quiet breath.

Front: What is vital capacity?
Back: The maximum air a person can exhale after a maximal inhalation.

Front: A spirometry graph shows reduced vital capacity. What might that suggest?
Back: Restricted lung function (e.g., weakened muscles, scarring, or disease) limiting how much air can be moved.

Front: What does a pulse oximeter measure?
Back: The percentage of hemoglobin saturated with oxygen (SpO2) in the blood.

Front: A client's SpO2 drops during exercise. What does this indicate?
Back: Oxygen demand may be outpacing delivery, suggesting reduced respiratory/cardiovascular capacity to clear them for that activity.
Why: Links to the 'clear a client for activity' skill.

Front: Why is it wrong to say most oxygen travels dissolved freely in the plasma?
Back: Most O2 is carried bound to hemoglobin inside red blood cells; only a small fraction dissolves in plasma, which is why hemoglobin levels strongly affect oxygen delivery.

Front: Why are the heart and lungs called a connected (cardiopulmonary) system?
Back: Blood is pumped to the lungs to load O2 and unload CO2, then returned to the heart to deliver O2 to the body - the two organs depend on each other.
Why: Core Unit 3 integration.

Front: Why does heart rate increase during exercise?
Back: Working muscles need more O2 and nutrients and produce more CO2, so the heart pumps faster to meet demand and clear waste.

Front: Innate vs adaptive immunity?
Back: Innate is the fast, nonspecific first line (skin, inflammation, phagocytes); adaptive is slower, specific, and has memory (B and T cells).
Why: Core compare/contrast.

Front: What is an antigen?
Back: A molecule (often on a pathogen) that the immune system recognizes as foreign and responds to.

Front: What is an antibody?
Back: A protein made by B cells that binds a specific antigen to neutralize or mark it for destruction.

Front: Why is the antigen-antibody interaction so specific?
Back: An antibody's shape is complementary to one antigen, so it binds that target only - structure determines function.

Front: B cells vs T cells?
Back: B cells make antibodies (humoral immunity); T cells kill infected cells or help coordinate the response (cell-mediated immunity).

Front: What is the first line of defense against pathogens?
Back: Physical/chemical barriers such as skin, mucus, and stomach acid.

Front: What is the role of phagocytes (e.g., macrophages)?
Back: They engulf and digest pathogens and cell debris (phagocytosis), part of innate defense.

Front: Name two functions of the lymphatic system.
Back: It returns fluid to the blood, filters lymph at lymph nodes, and houses immune cells.

Front: Why do lymph nodes swell during an infection?
Back: Immune cells proliferate there to fight the pathogen, enlarging the node.

Front: How does a vaccine create immunity without causing the disease?
Back: It exposes the body to a harmless form/part of a pathogen, triggering adaptive immunity and memory cells so a real infection is fought quickly.
Why: High-yield mechanism.

Front: Active vs passive immunity?
Back: Active immunity is made by your own immune response (infection or vaccine) and lasts long; passive immunity is borrowed antibodies (e.g., from mother or injection) and is temporary.

Front: Why is it wrong to think a vaccine works instantly the moment it is given?
Back: It takes days to weeks for the adaptive immune system to build memory cells and antibodies, so protection is not immediate after the dose.

Front: Why does herd immunity protect people who cannot be vaccinated?
Back: When most are immune, the pathogen spreads poorly, lowering exposure for the vulnerable.

Front: What does a plaque assay measure?
Back: The number of infectious virus particles, counted as clear zones (plaques) where viruses have lysed host cells in a lawn.

Front: How does a plaque form in the assay?
Back: A single virus infects a cell, replicates, and spreads to neighbors, killing a localized patch that appears as a clear plaque.

Front: Fewer plaques appear after adding an antiviral drug. What does that suggest?
Back: The antiviral reduced viral infectivity/replication - evidence it works.

Front: Why include an untreated (no-drug) plate in a plaque assay?
Back: It is the control/baseline showing normal viral plaque count so you can judge the drug's effect.

Front: Why does high altitude cause hypoxia?
Back: Lower air pressure means less oxygen available per breath, reducing blood O2 saturation.

Front: How does the body acclimatize to high altitude over time?
Back: It makes more red blood cells (and breathes faster) to carry more oxygen.

Front: What is risk mitigation in a medical/field context?
Back: Identifying hazards and taking steps to reduce their likelihood or severity.

Front: Name one risk-mitigation step for an expedition into a pathogen-prone region.
Back: Examples: vaccination, water treatment, PPE, prophylactic medication, or a medical evacuation plan.

Front: Why assess both likelihood and severity when ranking a health risk?
Back: A high-severity but rare event and a frequent minor one need different responses; combining both prioritizes resources effectively.

Front: An item asks you to 'relate structure to function' for the alveolus. What must your answer do?
Back: Describe the structure (thin, many, large surface area) AND explain how it enables efficient gas exchange.
Why: Core HBS reasoning move.

Front: A spirometry-CER prompt asks if a client is cleared for activity. What must you include?
Back: A claim, the specific spirometry/SpO2 data as evidence, and reasoning connecting the data to respiratory capacity.
Why: Mirrors the 'spirometry/clearance CER' evidence.

Front: What does a 'predict' cardiovascular prompt require beyond the outcome?
Back: The predicted result PLUS the physiological reasoning (e.g., why exercise raises heart rate).

Front: Strategy: how do you tackle an unfamiliar cardio/respiratory/immune term on a test?
Back: Break it into prefix + root + suffix and translate each part (e.g., tachy+cardi+a).
Why: Leverages MEDTERM word-part cards.

Front: How do the cardiovascular and respiratory systems work together to power activity?
Back: The respiratory system loads O2 into blood and removes CO2; the cardiovascular system transports that blood to tissues - together they meet metabolic demand.
Why: Core Unit 3 integration.

Front: How does gas exchange at the alveolus connect to cellular respiration (AP Bio)?
Back: O2 delivered by the blood is the final electron acceptor in cellular respiration, and the CO2 produced is carried back to be exhaled.
Why: Bridges HBS to AP Bio energetics.

Front: How does antibody specificity illustrate that structure determines function?
Back: An antibody's shape complements one antigen, so only the right fit binds - the same protein-shape logic seen in enzymes and receptors.

Front: How does diffusion explain both gas exchange and capillary nutrient transfer?
Back: In both, molecules move passively from high to low concentration across thin walls, no energy required.

Front: How does the immune response connect to homeostasis?
Back: It detects and removes pathogens/abnormal cells, restoring and protecting the body's stable internal state.

Front: Name the main components of blood.
Back: Plasma (liquid), red blood cells, white blood cells, and platelets.

Front: What does hemoglobin do?
Back: It binds and carries oxygen (and some CO2) in red blood cells.

Front: Red blood cells vs white blood cells (function)?
Back: Red cells transport oxygen; white cells defend against infection.

Front: What is the role of platelets?
Back: They help form clots to stop bleeding.

Front: Why does the body increase red blood cell production at high altitude?
Back: More red cells carry more oxygen to offset the lower oxygen availability.

Front: What is the function of the coronary arteries?
Back: They supply oxygen-rich blood to the heart muscle itself.

Front: Why does a blocked coronary artery cause a heart attack?
Back: Heart muscle downstream loses oxygen and begins to die without blood supply.

Front: What does the suffix -megaly mean (e.g., cardiomegaly)?
Back: Enlargement (cardiomegaly = enlarged heart).

Front: What does the root thromb/o- mean?
Back: Clot (e.g., thrombosis, thrombus).

Front: On an EKG, what does the P wave represent?
Back: Atrial depolarization (the atria contracting).

Front: Why does the 'lub-dub' heart sound occur?
Back: Heart valves snapping shut: 'lub' as AV valves close (start of systole), 'dub' as semilunar valves close (start of diastole).

Front: Why is high blood pressure (hypertension) dangerous over time?
Back: It strains the heart and damages vessels, raising risk of heart attack, stroke, and kidney damage.

Front: How does exhalation normally occur at rest?
Back: The diaphragm relaxes, chest volume decreases, pressure rises, and air flows out (passive).

Front: Inhalation vs exhalation in terms of pressure?
Back: Inhalation lowers lung pressure below atmospheric (air in); exhalation raises it above atmospheric (air out).

Front: What protein in red blood cells carries most oxygen?
Back: Hemoglobin.

Front: What primarily drives the urge to breathe?
Back: Rising blood CO2 (and falling pH) sensed by the brainstem, more than low O2.

Front: What does the root bronch/o- mean?
Back: Bronchus/airway (e.g., bronchitis, bronchodilator).

Front: Decode 'apnea' from its parts.
Back: A- (without) + -pnea (breathing) = absence of breathing.

Front: A spirogram shows a fast, deep breath. Which volume increases most above tidal volume?
Back: Inspiratory reserve volume - the extra air inhaled beyond a normal breath.

Front: What is inflammation?
Back: A nonspecific innate response (redness, heat, swelling, pain) that increases blood flow and brings immune cells to fight infection or injury.

Front: How does a fever help fight infection?
Back: Raising body temperature slows pathogen growth and speeds immune activity.

Front: What is a memory cell?
Back: A long-lived adaptive immune cell that responds faster and stronger on re-exposure to the same antigen.

Front: Why is the second exposure to a pathogen usually fought faster?
Back: Memory cells from the first exposure mount a quicker, stronger secondary response.

Front: Decode 'lymphoma' from its parts.
Back: Lymph/o (lymph) + -oma (tumor) = a tumor of lymphatic tissue.

Front: Why might a vaccine require a booster dose?
Back: To re-stimulate memory cells and maintain a high level of long-term protection.

Front: Plaque counts decrease as antiviral dose increases. What relationship is shown?
Back: A dose-dependent antiviral effect: more drug, fewer infectious viruses.

Front: Why is dehydration a major risk in extreme heat or altitude?
Back: Fluid loss reduces blood volume and impairs circulation, temperature regulation, and oxygen delivery.

Front: An EKG shows ~150 bpm with normal-shaped P, QRS, and T waves at rest. Name the finding and explain what the normal wave shapes tell you.
Back: Resting tachycardia (fast rate); normal wave morphology means each beat conducts normally, so the problem is rate (too fast), not a conduction defect.
Why: Interpret an EKG scenario.

Front: A patient with a blocked coronary artery develops chest pain and dying heart muscle downstream. Explain the cause-and-effect chain.
Back: The blockage cuts oxygen-rich blood supply to that region of heart muscle; deprived of O2, the tissue cannot make enough ATP and begins to die (heart attack).
Why: Trace cause to effect.

Front: A client's spirometry shows reduced vital capacity and SpO2 falls during exercise. Should they be cleared for strenuous activity, and on what evidence?
Back: No/cautiously: reduced vital capacity plus exercise desaturation indicate respiratory capacity may not meet demand, so clearance is not supported without further evaluation.
Why: Spirometry/clearance CER scenario.

Front: A climber at high altitude has an SpO2 of 82% and rapid breathing. Explain why altitude lowers SpO2 and why breathing speeds up.
Back: Lower air pressure means less O2 per breath, so hemoglobin saturation falls; the body breathes faster to take in more O2 and offload CO2.
Why: Apply gas-exchange to environment.

Front: A patient fights off a virus far faster the second time they encounter it. Which cells explain this, and what is the principle behind vaccination?
Back: Memory cells from the first exposure mount a faster, stronger secondary response; vaccines exploit this by creating memory without causing disease.
Why: Connect memory cells to vaccines.

Front: In a plaque assay, plates with increasing antiviral dose show progressively fewer plaques than the untreated control. What relationship does this support and why is the control essential?
Back: A dose-dependent antiviral effect (more drug, fewer infectious viruses); the untreated control gives the baseline plaque count needed to judge the drug's effect.
Why: Interpret assay with a control.

Q: Blood flows right atrium -> [...] -> [...] -> left atrium -> [...] -> body.
A: right ventricle; lungs; left ventricle

Q: In the cardiac cycle, [...] is contraction (pumping out) and [...] is relaxation (filling).
A: systole; diastole

Q: At the alveolus, [...] diffuses into the blood and [...] diffuses out, each moving down its [...] gradient.
A: oxygen; carbon dioxide; concentration

Q: [...] is the air moved in a normal breath, while [...] is the maximum exhaled after a maximal inhalation.
A: Tidal volume; vital capacity

Q: [...] immunity is fast and nonspecific, while [...] immunity is specific and has [...].
A: Innate; adaptive; memory

Q: An [...] is the foreign molecule recognized; an [...] is the protein made by [...] that binds it.
A: antigen; antibody; B cells

Q: [...] carry blood away from the heart under high pressure, while [...] return blood and contain [...] to prevent backflow.
A: Arteries; veins; valves

Front: What does the root nephr/o- mean?
Back: Kidney (e.g., nephron, nephritis, nephrology).
Why: Word-part decoding is heavily tested (MEDTERM 22%).

Front: What does the root ren/o- mean?
Back: Kidney (e.g., renal, renal artery).

Front: What does the root ur/o- (urin/o-) mean?
Back: Urine/urinary tract (e.g., urology, urinalysis).

Front: What does the suffix -uria mean?
Back: A urine condition (e.g., hematuria = blood in urine, glycosuria = sugar in urine).

Front: What does the prefix dia- mean (as in dialysis)?
Back: Through/across (dialysis = filtering across a membrane).

Front: What does the root gastr/o- mean?
Back: Stomach (e.g., gastritis, gastrointestinal).

Front: What does the root enter/o- mean?
Back: Intestine (e.g., gastroenteritis, enteric).

Front: What does the root hepat/o- mean?
Back: Liver (e.g., hepatitis, hepatic).

Front: What does the suffix -ase signal in enzyme names?
Back: An enzyme (e.g., lipase, amylase, protease).

Front: Decode 'hematuria' from its parts.
Back: Hemat/o (blood) + -uria (urine condition) = blood in the urine.
Why: Shows decode strategy.

Front: Decode 'gastroenteritis' from its parts.
Back: Gastr/o (stomach) + enter/o (intestine) + -itis (inflammation) = inflammation of stomach and intestine.

Front: What are the main functions of the kidneys?
Back: To filter blood, remove wastes (e.g., urea) as urine, and regulate water, electrolytes, and blood pH.

Front: What is the nephron?
Back: The functional filtering unit of the kidney that produces urine.
Why: Trunk structure for Unit 4 renal.

Front: What happens at the glomerulus?
Back: Blood pressure forces water and small solutes out of the capillaries into the nephron, forming the filtrate (filtration).
Why: High-yield mechanism.

Front: What is reabsorption in the nephron?
Back: Useful substances (glucose, water, ions) are returned from the filtrate back into the blood.

Front: Filtration vs reabsorption in the nephron?
Back: Filtration moves fluid/solutes OUT of blood into the nephron; reabsorption returns needed substances back INTO the blood.

Front: Why are large proteins and blood cells normally NOT in the filtrate?
Back: They are too big to pass through the glomerular filtration membrane, so they stay in the blood.

Front: Why does finding protein or blood cells in urine signal a problem?
Back: It suggests the filtration membrane is damaged and leaking molecules that should stay in the blood.
Why: Links to urinalysis interpretation.

Front: How do the kidneys help regulate blood pressure and water balance?
Back: By adjusting how much water and salt are reabsorbed vs excreted, changing blood volume.

Front: What is dialysis?
Back: A treatment that filters wastes and excess fluid from the blood when the kidneys fail, using a semipermeable membrane.

Front: What principle moves wastes across the dialysis membrane?
Back: Diffusion: wastes move from the high-concentration blood into the dialysate (low concentration) across the membrane.

Front: Why is the dialysate designed without the wastes but with needed solutes?
Back: So wastes diffuse out of the blood while needed substances (e.g., glucose, ions) do not diffuse away.

Front: Why is it wrong to say dialysis fully cures kidney failure?
Back: Dialysis replaces some filtering function but does not restore the kidneys; it manages the condition rather than curing it.

Front: Why must dialysis use a semipermeable membrane rather than a solid barrier?
Back: It must let small wastes pass through while keeping blood cells and proteins in - selective permeability.

Front: What is urinalysis?
Back: The physical, chemical, and microscopic analysis of urine to assess health.
Why: EBS is 18% of 072040.

Front: Glucose is found in a urine sample. What might that indicate?
Back: Possible diabetes/hyperglycemia, where excess blood glucose exceeds what the nephron can reabsorb.

Front: A urine sample shows high protein. What does that suggest?
Back: Possible kidney damage allowing protein to leak into the filtrate (proteinuria).

Front: Why standardize collection (e.g., timing, container) in urinalysis?
Back: To make samples comparable and avoid contamination that could skew results.

Front: Why is urine a useful diagnostic fluid?
Back: Its composition reflects kidney function and what the blood is carrying, revealing many conditions noninvasively.

Front: What does gel electrophoresis separate molecules by?
Back: For nucleic acids (uniform negative charge) and SDS-treated proteins, by size: smaller molecules migrate farther toward the positive electrode. Note: native (untreated) proteins separate by size, charge, AND shape.

Front: Why do DNA fragments move toward the positive electrode?
Back: DNA is negatively charged (phosphate backbone), so it migrates toward the positive pole.

Front: Two samples produce different band patterns. What can you infer?
Back: Their molecules differ in size/composition - useful for comparing DNA, proteins, or identifying variants.

Front: Why run a known size standard (ladder) alongside samples?
Back: It provides a reference to estimate the size of unknown bands.

Front: Why is it wrong to say larger fragments travel farther through the gel in electrophoresis?
Back: Smaller fragments move faster and farther because they pass through the gel matrix more easily; larger ones lag behind near the wells.

Front: Trace the path of food through the GI tract.
Back: Mouth -> esophagus -> stomach -> small intestine -> large intestine -> rectum/anus.

Front: Mechanical vs chemical digestion?
Back: Mechanical physically breaks food into smaller pieces (chewing, churning); chemical uses enzymes/acids to break bonds into absorbable molecules.

Front: Where is most nutrient absorption, and what structure maximizes it?
Back: The small intestine; villi and microvilli vastly increase surface area for absorption.
Why: Structure-to-function move.

Front: What is the main role of the large intestine?
Back: To absorb water and form/compact feces.

Front: What is a digestive enzyme?
Back: A protein that speeds the breakdown of a specific food molecule (e.g., amylase, lipase, protease).

Front: Amylase vs lipase vs protease - what does each break down?
Back: Amylase digests carbohydrates/starch; lipase digests fats; protease digests proteins.

Front: Why is each digestive enzyme specific to one substrate?
Back: Its active site shape is complementary to one substrate, so it only catalyzes that reaction - structure determines function.

Front: Why does stomach pepsin work best in acidic conditions but stop in the small intestine?
Back: Each enzyme has an optimal pH; pepsin needs the stomach's acid, and the neutral small intestine denatures/inactivates it.

Front: Predict what happens to fat digestion if lipase is deficient.
Back: Fats are not broken down well, leading to poor fat absorption (e.g., fatty stools).
Why: Predict-with-reasoning move.

Front: Why is it wrong to say enzymes are used up each time they catalyze a reaction?
Back: Enzymes are reusable catalysts; they emerge unchanged and can catalyze many reaction cycles, so they are not consumed by the reaction.

Front: What is the gut microbiome?
Back: The community of microorganisms (mostly bacteria) living in the digestive tract.

Front: Name one beneficial role of gut microbes.
Back: They help digest fiber, produce certain vitamins (e.g., K, some B), and support the immune system.

Front: Why can antibiotics disrupt digestion?
Back: They can kill beneficial gut bacteria along with pathogens, altering digestion and immunity.

Front: Why is the host-microbiome relationship described as mutualistic?
Back: Microbes get nutrients and habitat while the host gains digestion, vitamins, and protection - both benefit.

Front: An item asks you to 'relate structure to function' for the nephron or villi. What must your answer do?
Back: Describe the structure AND explain how it enables its function (filtration or absorption), not just name it.
Why: Core HBS reasoning move.

Front: A urinalysis-CER prompt gives lab values. What must your answer include?
Back: A claim about the patient, the specific urinalysis values as evidence, and reasoning linking them to renal function.
Why: Mirrors the patient-perspective evidence.

Front: What does a 'predict' digestive/renal prompt require beyond the outcome?
Back: The predicted result PLUS the physiological reasoning for why it occurs.

Front: Strategy: how do you tackle an unfamiliar renal/digestive term on a test?
Back: Break it into prefix + root + suffix and translate each part (e.g., hemat+uria).
Why: Leverages MEDTERM word-part cards.

Front: Why does HBS frame Unit 4 around patient 'perspectives'?
Back: It connects body-system science to real patient experiences, helping students reason about diagnosis, treatment, and quality of life.

Front: How do the digestive and circulatory systems work together?
Back: The digestive system breaks food into absorbable molecules; the circulatory system transports those nutrients to cells throughout the body.
Why: Core Unit 4 integration.

Front: How do the kidneys support homeostasis?
Back: They regulate water, electrolytes, pH, and waste removal, keeping the internal environment stable.

Front: How does enzyme specificity in digestion parallel enzyme function in AP Bio?
Back: Both depend on active-site/substrate complementarity (lock-and-key/induced fit); structure determines which reaction is catalyzed.
Why: Bridges HBS to AP Bio.

Front: How does dialysis apply the same diffusion principle as alveolar gas exchange?
Back: Both move molecules passively across a semipermeable membrane down a concentration gradient, no energy required.
Why: Connects Unit 4 to Unit 3.

Front: How does nephron filtration relate to selective permeability seen in cells?
Back: The glomerular membrane lets small molecules pass while blocking large ones - the same selective-permeability logic as a cell membrane.

Front: Name the structures urine passes through after leaving the kidney.
Back: Ureter -> urinary bladder -> urethra -> out of the body.

Front: What is the main nitrogenous waste the kidneys excrete?
Back: Urea (a byproduct of protein breakdown).

Front: What is secretion in the nephron?
Back: The active transfer of additional wastes/ions from the blood into the filtrate to be excreted.

Front: How do the kidneys help regulate blood pH?
Back: By excreting or retaining hydrogen ions and bicarbonate to keep blood pH in a narrow range.

Front: Why does dehydration lead to more concentrated urine?
Back: The kidneys reabsorb more water to conserve it, producing less, more concentrated urine.

Front: Why are the kidneys considered excretory AND regulatory organs?
Back: They remove wastes (excretion) and also regulate water, electrolytes, and pH (homeostasis).

Front: Hemodialysis vs the natural kidney - one key difference?
Back: Hemodialysis filters blood through an external machine/membrane; the kidney does it continuously with living nephrons that also reabsorb selectively.

Front: What does the suffix -lysis mean (as in dialysis)?
Back: Breaking down/separation/loosening.

Front: What does the root cyst/o- mean (urinary context)?
Back: Bladder (e.g., cystitis = bladder inflammation).

Front: Decode 'nephritis' from its parts.
Back: Nephr/o (kidney) + -itis (inflammation) = inflammation of the kidney.

Front: A urine sample is very dark and low volume. What might it indicate?
Back: Dehydration - the kidneys are conserving water, concentrating the urine.

Front: Bacteria and white blood cells appear in a urine sample. What is suggested?
Back: A urinary tract infection.

Front: Name two physical properties checked in a urinalysis.
Back: Examples: color, clarity/turbidity, and specific gravity (concentration).

Front: Why is electrophoresis useful for diagnosing some genetic conditions?
Back: It can reveal abnormal protein or DNA fragment patterns (e.g., sickle-cell hemoglobin) by their distinct band positions.

Front: What pulls molecules through the gel in electrophoresis?
Back: An electric field (current) applied across the gel.

Front: What is the role of the liver in digestion?
Back: It produces bile, which emulsifies fats to aid their digestion and absorption.

Front: What does the gallbladder do?
Back: It stores and concentrates bile, releasing it into the small intestine.

Front: What is the role of the pancreas in digestion?
Back: It secretes digestive enzymes and bicarbonate into the small intestine.

Front: Why does the stomach produce acid (HCl)?
Back: Acid kills many pathogens and provides the low pH that activates pepsin for protein digestion.

Front: Why does damage to intestinal villi (e.g., celiac disease) cause malnutrition?
Back: Reduced surface area lowers nutrient absorption even when food is eaten.

Front: What is peristalsis?
Back: Wavelike smooth-muscle contractions that move food along the GI tract.

Front: Where does carbohydrate digestion begin and with what enzyme?
Back: In the mouth, with salivary amylase.

Front: Predict the effect of an enzyme at a temperature far above its optimum.
Back: It denatures (loses shape), so its active site no longer works and the reaction stops.

Front: What does the suffix -emesis mean?
Back: Vomiting (e.g., hematemesis = vomiting blood).

Front: What does the root chol/e- mean?
Back: Bile/gall (e.g., cholecystitis = gallbladder inflammation).

Front: Decode 'hepatitis' from its parts.
Back: Hepat/o (liver) + -itis (inflammation) = inflammation of the liver.

Front: Why is it wrong to say all gut bacteria are harmful?
Back: Most gut bacteria are harmless or beneficial, aiding digestion of fiber, vitamin production, and immune support; only some are pathogenic.

Front: Why might probiotics be taken after a course of antibiotics?
Back: To help restore beneficial gut bacteria that the antibiotics reduced.

Front: A patient on long-term dialysis becomes anemic (low red blood cell count). Knowing a healthy kidney also makes erythropoietin, explain why.
Back: Healthy kidneys secrete erythropoietin (EPO), which stimulates red blood cell production. In kidney failure, EPO falls, so fewer red cells are made and anemia develops; dialysis filters blood but does not replace this hormone role.

Front: Excretion vs elimination?
Back: Excretion removes metabolic wastes from the blood (e.g., urea in urine); elimination expels undigested material (feces).

Front: Why is it wrong to say most chemical digestion happens in the stomach?
Back: Most chemical digestion and nearly all absorption occur in the small intestine, using pancreatic and intestinal enzymes plus bile; the stomach mainly begins protein digestion.

Front: How does 'explain' differ from 'identify' on an HBS item?
Back: 'Identify' = name briefly; 'explain' = give the how/why mechanism.

Front: Why is timing/frequency important for a dialysis patient?
Back: Wastes and fluid build up continuously, so regular sessions are needed to keep them in a safe range.

Front: Filtration vs secretion in waste removal?
Back: Filtration passively forces fluid/solutes out of blood at the glomerulus; secretion actively adds specific extra wastes to the filtrate later.

Front: Substrate vs product of an enzyme reaction?
Back: The substrate is what the enzyme acts on; the product is what the reaction yields (e.g., starch -> sugars by amylase).

Front: Why does removing the gallbladder usually still allow fat digestion?
Back: The liver still makes bile; it just drips directly into the intestine instead of being stored and concentrated.

Front: Why is it wrong to assume a trace of glucose or protein in urine is always normal?
Back: Healthy urine has essentially no glucose and only minimal protein; notable amounts can signal hyperglycemia or kidney damage and warrant investigation.

Front: A urinalysis shows glucose AND protein present. Interpret what each finding suggests about this patient's physiology.
Back: Glucose suggests blood sugar has exceeded the nephron's reabsorption capacity (possible diabetes); protein suggests a damaged filtration membrane leaking large molecules (possible kidney damage).
Why: Interpret combined lab values.

Front: A patient produces little lipase. Predict the effect on fat digestion and one observable symptom, with reasoning.
Back: Fats are poorly broken down and absorbed because lipase is the fat-digesting enzyme; an observable result is fatty, greasy stools (steatorrhea).
Why: Predict from a missing enzyme.

Front: A patient with damaged intestinal villi (celiac disease) eats enough food but is malnourished. Explain the apparent contradiction.
Back: Villi provide the surface area for absorption; when they are damaged, nutrients pass through without being absorbed, so adequate intake still leaves the patient malnourished.
Why: Resolve a structure-function paradox.

Front: After heavy sweating with no water intake, a person's urine is dark and low in volume. Trace the renal response that explains this.
Back: Low body water triggers increased water reabsorption in the nephron (less excreted), conserving fluid and producing small amounts of concentrated, dark urine.
Why: Trace a homeostatic response.

Front: A hemoglobin gel-electrophoresis run shows a patient's band sitting at a different position than the normal control band. What can you infer and what does the control provide?
Back: The patient's hemoglobin differs in size/charge from normal (e.g., a variant such as sickle-cell hemoglobin); the normal control gives the reference position needed to detect the shift.
Why: Interpret electrophoresis bands.

Q: At the [...], blood pressure forces water and small solutes into the nephron ([...]); useful substances are then returned to blood by [...].
A: glomerulus; filtration; reabsorption

Q: Dialysis filters blood using a [...] membrane, with wastes moving out by [...] into the dialysate.
A: semipermeable; diffusion

Q: For nucleic acids and SDS-treated proteins, gel electrophoresis separates by [...]; [...] fragments travel farther, and DNA (uniformly negative) moves toward the [...] electrode.
A: size; smaller; positive

Q: [...] digests carbohydrates, [...] digests fats, and [...] digests proteins.
A: Amylase; lipase; protease

Q: Most nutrient absorption occurs in the [...], where [...] increase surface area; the [...] absorbs water.
A: small intestine; villi; large intestine

Q: Finding [...] in urine may signal diabetes, while [...] in urine may signal kidney damage.
A: glucose; protein

Q: The gut [...] helps digest [...] and produce certain vitamins, a [...] relationship with the host.
A: microbiome; fiber; mutualistic