Question 1

Which organ is responsible for RBC production in adults?

Accepted Answer

Answer reason: In adults, erythropoiesis occurs primarily in the red marrow of bones (especially the axial skeleton), where hematopoietic stem cells differentiate into mature red blood cells. The kidney’s main role is endocrine regulation via erythropoietin release in response to hypoxia, not direct RBC formation. The liver is a major site of fetal hematopoiesis, and the spleen mainly filters and removes aged or abnormal RBCs, with extramedullary hematopoiesis only in certain disease states.
Category reason: This tests where erythropoiesis occurs in the adult body, a foundational body-function concept, so it fits Physiology rather than a nursing intervention or safety decision.

Question 2

Which of the following is NOT a component of blood plasma?

Accepted Answer

Answer reason: Plasma is the liquid portion of blood that contains water, electrolytes, and dissolved proteins such as albumin, globulins, and fibrinogen. Platelets are formed elements (cell fragments) suspended in plasma, not part of the plasma itself. When blood clots, fibrinogen in plasma is consumed to form fibrin, which is why serum lacks fibrinogen.
Category reason: This question tests knowledge of blood components and what constitutes plasma versus formed elements, which is a foundational concept in physiology.

Question 3

Which finding is normal for a 4-year-old child?

Accepted Answer

Answer reason: B) Riding a tricycle By age 4, gross motor skills commonly include pedaling and steering a tricycle (often achieved around age 3–4). Two-word sentences are expected much earlier (around age 2), and a 4-year-old typically speaks in longer phrases/sentences. Jumping with both feet is usually mastered by about age 2, so inability at 4 suggests delay. Following simple directions is expected in toddler years, so inability at 4 is not typical development.
Category reason: This question tests normal child developmental milestones (motor and language), which is foundational knowledge about human growth and function and best fits Physiology rather than a nursing intervention scenario.

Question 4

Which developmental milestone should a 9-month-old achieve?

Accepted Answer

Answer reason: c) Sitting without support Gross motor development typically includes sitting independently by around 6–9 months, making this an expected milestone at 9 months. Walking independently is more typical closer to 12–15 months. Using a spoon is usually a later fine-motor/self-feeding skill (around 12–18 months). Speaking in short phrases is a language milestone expected closer to 18–24 months rather than at 9 months.
Category reason: This question tests normal infant developmental milestones (gross motor development timing), which is foundational human development physiology rather than a nursing intervention or prioritization scenario.

Question 5

The number of calories required to raise the temperature of 1g of water from 15 to 16°C is called?

Accepted Answer

Answer reason: This describes the definition of specific heat (heat capacity): the amount of heat energy needed to raise the temperature of a unit mass of a substance by 1°C. For water, 1 calorie raises 1 gram of water by 1°C (historically referenced from 15°C to 16°C). Heat of vaporization instead refers to energy required for a phase change from liquid to gas at constant temperature, so it does not apply here. The other options are not standard definitions for this measurement.
Category reason: This tests a foundational thermodynamics concept (heat required to raise temperature of water), which is part of basic physiology/biophysics rather than nursing clinical decision-making.

Question 6

ABG: pH = 7.36. PaCO2 = 30 mmHg, HCO3- = 18 mEq/L. Which disorder is shown?

Accepted Answer

Answer reason: The pH is low-normal (near 7.35) with a clearly decreased bicarbonate, indicating a primary metabolic acidosis. The PaCO2 is also low, showing respiratory compensation via hyperventilation to reduce carbonic acid. Using Winter’s formula, expected PaCO2 ≈ 1.5(18) + 8 ± 2 = 33–37 mmHg; the measured 30 is slightly lower but still consistent with strong/near-appropriate compensation and a near-normal pH. Therefore this fits a metabolic acidosis with compensation rather than isolated respiratory alkalosis or a normal ABG.
Category reason: This question tests interpretation of arterial blood gas values and acid–base compensation mechanisms, which is core physiology rather than a nursing intervention or prioritization scenario.

Question 7

Which of the following hormones is primarily responsible for increasing water reabsorption in the kidneys, thus reducing urine output?

Accepted Answer

Answer reason: ADH acts on V2 receptors in the kidney collecting ducts to insert aquaporin-2 water channels, increasing free-water reabsorption. This concentrates urine and decreases urine volume (antidiuresis), helping maintain plasma osmolality and circulating volume. Aldosterone primarily increases sodium reabsorption (with water following secondarily), ANP promotes natriuresis/diuresis, and PTH mainly regulates calcium and phosphate handling.
Category reason: This question tests the physiologic role of specific hormones in renal water handling and urine output regulation, which is a core concept in Physiology.

Question 8

Hemoglobin in humans has the highest affinity for which of the following gases?

Accepted Answer

Answer reason: Carbon monoxide binds to hemoglobin at the heme iron with an affinity ~200–250 times greater than oxygen, forming carboxyhemoglobin. This both reduces the number of available oxygen-binding sites and shifts the oxyhemoglobin dissociation curve to the left, impairing oxygen unloading to tissues. Methane and nitrous oxide do not significantly bind hemoglobin, and carbon dioxide is primarily transported as bicarbonate or bound to globin chains (carbaminohemoglobin) rather than having the strongest heme-site affinity.
Category reason: This tests gas transport and hemoglobin binding characteristics, a core concept in respiratory physiology rather than a nursing-intervention scenario.

Question 9

A patient with low erythropoietin levels may develop which condition?

Accepted Answer

Answer reason: Erythropoietin (primarily produced by the kidneys) stimulates the bone marrow to produce red blood cells. When erythropoietin levels are low, erythropoiesis decreases, leading to reduced red blood cell mass and a lower hemoglobin/hematocrit. This mechanism is classically seen in chronic kidney disease and results in anemia rather than electrolyte, blood pressure, or glucose abnormalities.
Category reason: This question tests the physiologic role of erythropoietin in red blood cell production and the consequence of decreased hormone levels, which is a core Physiology concept rather than a nursing intervention scenario.

Question 10

Yellow color of urine in due to Presences of?

Accepted Answer

Answer reason: Urochrome (also called urobilin) is a normal pigment derived from hemoglobin breakdown and is primarily responsible for the typical yellow color of urine. Its concentration varies with hydration status, making urine appear pale yellow when dilute and darker yellow when concentrated. Cholesterol and lymph are not normal pigments that determine urine color, and bile pigments more typically cause dark yellow-brown urine when present (e.g., cholestasis).
Category reason: This item tests the normal physiologic basis of urine coloration and pigment metabolism rather than a nursing intervention or patient-care decision, so it fits Physiology under NursingScience.

Question 11

Daily production of saliva is about?

Accepted Answer

Answer reason: Normal salivary secretion in adults is commonly cited at about 1 to 1.5 liters per day, varying with hydration status, autonomic stimulation, medications (e.g., anticholinergics), and sleep (lower flow). Values like 2–2.3 liters/day are higher than typical baseline physiology for most individuals. Among the options provided, the closest standard “about” value is 1 liter/day.
Category reason: This question tests normal body fluid secretion rates (salivary gland output), which is a foundational function of the digestive/oral system and therefore belongs to Physiology rather than nursing care decisions.

Question 12

Vitamin supplementation needed after gastrectomy is?

Accepted Answer

Answer reason: After gastrectomy, loss of gastric parietal cells reduces intrinsic factor production, which is required for ileal absorption of cobalamin. This leads to progressive deficiency over months to years, causing megaloblastic anemia and possible neurologic symptoms. Therefore routine long-term replacement (often parenteral or high-dose oral depending on the surgery type) is indicated.
Category reason: This tests the physiologic basis of nutrient absorption after removal of the stomach (intrinsic factor–dependent cobalamin absorption), which is foundational biomedical knowledge rather than a nursing action/prioritization scenario.

Question 13

Which organ is primarily responsible for detoxifying the body?

Accepted Answer

Answer reason: a) Liver The liver is the body’s main site for biotransformation of drugs, toxins, and metabolic waste via Phase I (e.g., cytochrome P450) and Phase II conjugation reactions, which make substances less toxic and more water-soluble for elimination. It also detoxifies endogenous compounds such as ammonia by converting it to urea. While kidneys excrete many waste products, they are primarily responsible for filtration and elimination rather than the core biochemical detoxification processes.
Category reason: This item tests foundational organ function—detoxification/biotransformation roles of the liver—making it a physiology knowledge question rather than a nursing judgment or intervention scenario.

Question 14

Glycogen is mainley stored in?

Accepted Answer

Answer reason: The liver is a primary storage site for glycogen and plays a central role in maintaining blood glucose between meals via glycogenolysis and gluconeogenesis. Although skeletal muscle also stores large amounts of glycogen, that glycogen is used locally for muscle activity and cannot be directly released as free glucose into the bloodstream due to lack of glucose-6-phosphatase. The thyroid and kidney are not major glycogen storage organs under normal physiology.
Category reason: This question tests knowledge of carbohydrate storage and glucose homeostasis, which are core concepts in Physiology rather than nursing care actions.

Question 15

In a hospital error, a 60-year-old woman is infused with large volumes of a solution that causes lysis of her red blood cells (RBCs). The solution was most likely?

Accepted Answer

Answer reason: Red blood cell lysis occurs when the intracellular environment becomes effectively hypotonic, driving water into cells until they rupture. Urea is a penetrating solute that rapidly crosses the RBC membrane, so an initially isosmotic urea solution becomes effectively hypotonic as urea equilibrates into the cell, increasing intracellular osmoles and pulling water inward. In contrast, NaCl and mannitol are effectively nonpenetrating (tonic) solutes at these concentrations and therefore do not cause osmotic swelling/hemolysis. Hypertonic solutions would shrink RBCs rather than lyse them.
Category reason: This item tests osmolarity vs tonicity and membrane permeability effects on red blood cell volume, which is a core concept in cellular and fluid physiology rather than a nursing management/intervention scenario.

Question 16

A fluid part of the blood is called?

Accepted Answer

Answer reason: Blood consists of a liquid component and formed elements. The liquid component is plasma, which is mostly water and contains proteins (albumin, globulins, fibrinogen), electrolytes, nutrients, hormones, and waste products. Platelets and erythrocytes are formed elements (cellular components), and “corpuscle” refers broadly to formed elements rather than the fluid portion.
Category reason: This is a foundational question about the components of blood and their functions, which is primarily studied under Physiology rather than nursing care decision-making.

Question 17

What is the function of saliva digestion?

Accepted Answer

Answer reason: Saliva contains salivary amylase (ptyalin), an enzyme that begins chemical digestion in the mouth by hydrolyzing complex carbohydrates into smaller sugars such as maltose and dextrins. This initiates carbohydrate digestion before the food reaches the stomach. Proteins are primarily digested by gastric and pancreatic proteases, and most fat digestion occurs via lingual/pancreatic lipase later in the GI tract. Dietary fiber is not digested by human enzymes.
Category reason: This tests the normal enzymatic role of saliva in the digestive process, which is a core concept of gastrointestinal physiology rather than a nursing intervention or clinical decision.

Question 18

The normal PH of body fluid is _?

Accepted Answer

Answer reason: This range reflects normal arterial blood pH, maintained tightly by buffer systems, the lungs (CO2 regulation), and the kidneys (bicarbonate handling). Values below this indicate acidemia and above this indicate alkalemia, both of which can impair enzyme function and cellular metabolism. The other ranges are not compatible with normal systemic body fluid pH and would represent extreme alkalinity or marked acidity.
Category reason: This item tests normal acid–base balance values of body fluids, a foundational function of homeostasis covered under Physiology rather than nursing interventions or prioritization.

Question 19

Which Structure vibrates in response to Sound waves?

Accepted Answer

Answer reason: B) Eardrum Sound waves entering the external ear strike the tympanic membrane, causing it to vibrate at the same frequency as the sound. These vibrations are then transmitted via the ossicles (malleus, incus, stapes) to the oval window. The cochlea converts the resulting fluid waves into neural signals, while the auditory nerve carries those signals to the brain rather than vibrating in response to sound itself.
Category reason: This question tests the functional mechanism of hearing (how sound waves are converted into mechanical vibrations and then neural signals), which is a core concept in physiology.

Question 20

How much is the amount of plasma in blood?

Accepted Answer

Answer reason: In normal whole blood, plasma comprises the majority of the volume, while the formed elements (primarily red blood cells) make up the remainder. Typical values are about 55% plasma and about 45% formed elements, reflected by an average hematocrit near 45%. This proportion can shift with dehydration, overhydration, anemia, or polycythemia, but the standard physiologic reference remains approximately 55%.
Category reason: This question tests the normal proportion of plasma in whole blood, a foundational concept about body fluid composition and circulating blood components, which is core Physiology.

Question 21

The part of the brain responsible for regulating body temperature is the ____________.?

Accepted Answer

Answer reason: B) Hypothalamus It serves as the body’s primary thermoregulatory center, integrating input from peripheral and central thermoreceptors and coordinating heat-loss and heat-production responses. It triggers autonomic and endocrine mechanisms such as sweating, shivering, vasodilation/vasoconstriction, and behavioral drives (e.g., seeking warmth/coolth). The hippocampus is mainly involved in memory, and the cerebellum primarily coordinates motor activity and balance rather than temperature homeostasis.
Category reason: This is a foundational question about how a brain region controls a normal body function (temperature homeostasis), which is primarily physiology rather than nursing care decision-making.

Question 22

Which of the following part of the brain controls breathing in human being?

Accepted Answer

Answer reason: It contains the primary respiratory centers that generate and regulate the basic rhythm of breathing and adjust ventilation in response to blood CO2/pH. These autonomic functions are part of the brainstem’s vital control systems. The cerebrum is responsible for higher cognition and voluntary control, the cerebellum coordinates movement and balance, and the spinal cord mainly conducts neural signals and mediates reflexes rather than initiating respiratory rhythm.
Category reason: This item tests foundational control of respiration by specific brain structures, which is a core concept in Physiology rather than a nursing care decision.

Question 23

WHICH ELECTROLYTE IMBALANCE IS MOST ASSOCIATED WITH CARDIAC DYSRHYTHMIAS?

Accepted Answer

Answer reason: Low potassium increases myocardial cell excitability and delays repolarization, predisposing to ectopy and ventricular dysrhythmias. Typical ECG changes include flattened/inverted T waves, ST depression, and prominent U waves, and it increases risk of digoxin-related arrhythmias. Compared with sodium, calcium, and magnesium disturbances listed, potassium abnormalities are most classically and strongly linked with clinically significant dysrhythmias.
Category reason: This item tests how electrolyte levels affect cardiac electrical activity and membrane excitability, which is primarily a foundational body-function concept within Physiology rather than a nursing action/prioritization scenario.

Question 24

At synapse which structure contains neuro transmitters-?

Accepted Answer

Answer reason: Neurotransmitters are stored in membrane-bound vesicles within the presynaptic terminal and are released by exocytosis when an action potential triggers calcium influx. The synaptic cleft is the extracellular gap where neurotransmitters diffuse after release, not a storage site. Synaptic knobs (axon terminals) contain the vesicles but the specific structure that holds the neurotransmitters is the vesicle. Schwann cells are peripheral glial cells involved in myelination and do not store synaptic neurotransmitters.
Category reason: This is a foundational question about where neurotransmitters are stored and released at a synapse, which is a core concept of neuronal function and therefore falls under Physiology rather than nursing care decisions.

Question 25

A(n) ________ is the movement of an action potential along an axon.?

Accepted Answer

Answer reason: A) is the movement of an action potential along an axon This describes propagation (conduction) of the nerve impulse, where sequential depolarization and repolarization occur along the axonal membrane. The direction and speed depend on factors like myelination and axon diameter, but the defining feature is movement of the action potential along the axon. The other choices describe ion movement directions or a nonspecific statement about speed rather than defining the process.
Category reason: This tests how nerve impulses travel along neurons, a foundational concept of neural signaling and membrane potentials, which is part of Physiology.

Question 26

Unmyelinated axon: slow nerve impulses:

Accepted Answer

Answer reason: B) myelinated axon: fast nerve impulses Myelin increases the speed of action potential conduction by enabling saltatory conduction between nodes of Ranvier, which is faster than continuous conduction in unmyelinated fibers. This directly contrasts with unmyelinated axons, where impulses propagate more slowly along the entire membrane. The other options contain inaccurate statements about neuronal structure or the pathway of impulse transmission.
Category reason: This question tests how myelination affects nerve impulse conduction speed, which is a core concept in neurophysiology rather than a nursing intervention or clinical judgment scenario.

Question 27

Why does a reflex arc result in a very quick response?

Accepted Answer

Answer reason: B) because the impulse does not travel to the brain Reflexes are mediated primarily at the spinal cord (or brainstem) level through a short reflex pathway, allowing a rapid motor response without first requiring cortical processing. Sensory input synapses quickly—often through an interneuron—onto motor neurons to produce immediate action. Although the brain may be informed after the response, bypassing higher-level processing is what makes the response fast.
Category reason: This question tests the physiological mechanism of reflex arcs and neural signal pathways rather than nursing interventions or clinical decision-making, so it belongs to Physiology.

Question 28

Neurotransmitters are ...?

Accepted Answer

Answer reason: D) released at synapses Neurotransmitters are chemical messengers stored in presynaptic vesicles and released into the synaptic cleft in response to an action potential. They bind to receptors on the postsynaptic membrane to alter ion flow or activate second-messenger pathways, changing the target cell’s activity. They are not the electrical impulse itself, and their presence is not limited to myelinated neurons. They are synthesized primarily by neurons (and some specialized cells), not by muscles as a general rule.
Category reason: This question tests how neuronal signaling works at the synapse, which is a core concept of body function and cell communication in Physiology.

Question 29

Nodes of Ranvier

Accepted Answer

Answer reason: A) are gaps in the myelin sheath These are periodic interruptions in the myelin covering of a myelinated axon where the axonal membrane is exposed. They enable saltatory conduction by concentrating voltage-gated sodium channels, allowing the action potential to “jump” between nodes and thereby speed conduction. They are normal anatomical features, not signs of axonal malfunction, and they do not slow impulses. Myelin provides insulation and helps protect axons, but the nodes themselves are defined by the absence of myelin at those points.
Category reason: This item tests foundational neurophysiology about myelination and action potential conduction, which fits Physiology rather than nursing-care decision making.

Question 30

Vitamin B 12 is absorbed in which part of GIT?

Accepted Answer

Answer reason: Vitamin B12 absorption occurs in the terminal ileum after it binds to intrinsic factor produced by gastric parietal cells. This receptor-mediated uptake is specific to the distal small intestine, not the duodenum or jejunum. Diseases or resection of the terminal ileum therefore commonly lead to B12 deficiency and megaloblastic anemia.
Category reason: This item tests where a nutrient is absorbed along the gastrointestinal tract, which is a core concept of digestive physiology.

Question 31

In the physiology of pain, the first stage is known as...?

Accepted Answer

Answer reason: Tissue injury or noxious stimulation is first converted by peripheral nociceptors into electrical impulses at the site of injury. This conversion step initiates nociceptive signaling before impulses can be carried to the spinal cord and brain. After this, signals undergo transmission through afferent pathways, then are perceived in the CNS, and can be modified by inhibitory/facilitatory mechanisms (modulation).
Category reason: This item tests the sequence of nociception stages (how pain signaling begins and is processed), which is a foundational body-function concept in physiology rather than a nursing intervention or prioritization decision.

Question 32

The autonomic nervous system controls?

Accepted Answer

Answer reason: A) involuntary functions of the internal organs The autonomic nervous system regulates visceral activities such as heart rate, blood pressure, gastrointestinal motility, pupil size, and glandular secretion without conscious control. It acts through sympathetic and parasympathetic divisions to maintain homeostasis. Locomotion and voluntary movement are mediated by the somatic motor system, and common spinal reflexes are primarily somatic reflex arcs rather than autonomic control.
Category reason: This question tests physiological function of the autonomic nervous system (visceral involuntary regulation), which is a core concept in Physiology rather than a nursing intervention or prioritization scenario.

Question 33

Hair cells in the semicircular canals detect?

Accepted Answer

Answer reason: The semicircular canals are part of the vestibular system and specifically sense angular (rotational) acceleration. Movement of endolymph deflects the cupula, bending the stereocilia of hair cells and changing their firing rate. This transduces head motion into neural signals carried by the vestibular branch of CN VIII. The other options relate to vision (light) or cochlear function (sounds/loudness), not semicircular canal physiology.
Category reason: This question tests how vestibular hair cells function to detect head movement, which is a foundational body-function concept in the nervous/vestibular physiology domain.

Question 34

Something that causes your nervous system or endocrine system to produce a response is called?

Accepted Answer

Answer reason: D) stimulus A stimulus is any internal or external change that triggers a response in the body’s control systems. The nervous and endocrine systems detect stimuli via receptors, then process and coordinate responses to maintain homeostasis. A receptor is the structure that detects the stimulus, while “message” refers to signaling (e.g., neurotransmitters/hormones) rather than the triggering event itself.
Category reason: This item tests the basic concept of how the nervous and endocrine systems initiate responses to changes, which is core Physiology rather than a nursing intervention or clinical judgment scenario.

Question 35

A reflex is all of the following except?

Accepted Answer

Answer reason: Reflex actions are rapid, involuntary responses to a stimulus that occur without conscious intention. They are typically mediated by reflex arcs at the spinal cord or brainstem level to minimize response time. While higher brain centers can modulate some reflexes, the basic reflex response does not require cortical control.
Category reason: This question tests the physiological definition and control mechanisms of reflexes, which is a core concept in nervous system function rather than a nursing intervention scenario.

Question 36

Which electrolyte is essential for neuromuscular function?

Accepted Answer

Answer reason: Neuromuscular excitability depends on ionic gradients and membrane potentials. Sodium influx is key for action potential depolarization, potassium efflux is crucial for repolarization and resting membrane potential, and calcium regulates neurotransmitter release at the neuromuscular junction and influences muscle contraction. Therefore, all three electrolytes are essential to normal neuromuscular function.
Category reason: This item tests foundational mechanisms of nerve impulse conduction and muscle contraction, which is core Physiology rather than a nursing care decision.

Question 37

A client with cancer is admitted to the oncology unit. Stat lab values reveal Hgb 12.6, WBC 6500, K+ 1.9, uric acid 7.0, Na+ 136, and platelets 17,800. The nurse evaluates that the client is experiencing which of the following?

Accepted Answer

Answer reason: A potassium level of 1.9 mEq/L is critically low and indicates a severe electrolyte imbalance. Such levels raise immediate concern for dangerous cardiac dysrhythmias and neuromuscular weakness. The sodium value is normal (136), and the WBC is normal (6500), making hypernatremia and leukocytosis incorrect. Although platelets are markedly low (17,800), the most direct interpretation among the listed options based on the labs is the potassium abnormality.
Category reason: This question primarily tests interpretation of electrolyte laboratory values (potassium) and the physiologic consequences of hypokalemia rather than a nursing intervention or prioritization decision.

Question 38

Sensory neurons transmit messages?

Accepted Answer

Answer reason: Sensory (afferent) neurons carry impulses from sensory receptors toward the central nervous system for processing and integration. This direction is opposite of motor (efferent) pathways, which travel from the CNS to muscles or glands. Signals may enter the spinal cord for reflexes or ascend to the brain for conscious perception and higher-level interpretation.
Category reason: This question tests the direction of nerve impulse transmission (afferent vs efferent), which is a foundational concept in nervous system function and belongs to Physiology.

Question 39

The division of the autonomic nervous system that keeps you breathing when you fall asleep?

Accepted Answer

Answer reason: Automatic breathing during sleep is maintained by involuntary autonomic control rather than voluntary motor control. Parasympathetic activity predominates during rest and sleep and supports baseline homeostatic functions such as heart rate slowing and regular respiration. Somatic control is voluntary (e.g., consciously holding your breath), and sympathetic activity is primarily for fight-or-flight responses rather than routine ventilation. “Central” is not a division of the autonomic nervous system.
Category reason: This tests basic physiologic control of respiration and autonomic nervous system function, which falls under Physiology rather than nursing care decision-making.

Question 40

A very low-calorie diet will?

Accepted Answer

Answer reason: With significant calorie restriction, the body reduces resting energy expenditure to conserve fuel, a physiologic adaptation often called adaptive thermogenesis. Thyroid hormone conversion (T4 to active T3) and sympathetic activity can decrease, lowering basal metabolic rate. As glycogen and lean mass may decline, total daily energy expenditure can further drop, making weight loss slower over time and promoting regain when intake increases.
Category reason: This tests the physiologic regulation of energy expenditure and metabolic rate in response to caloric restriction, which is core Physiology rather than a nursing-care intervention scenario.

Question 41

What nutrient is your body mainly made of?

Accepted Answer

Answer reason: The human body is composed predominantly of water (roughly ~50–70% by weight depending on age, sex, and body composition). Water is the primary medium for cellular reactions, circulation, temperature regulation, and transport of nutrients and wastes. While proteins and fats are essential structural and energy components, they make up a smaller proportion of total body mass than water.
Category reason: This is a foundational question about overall body composition and how much of the body is made up of water, which is primarily a physiology concept.

Question 42

Which area of the brain acts as the principal regulator of body temperature?

Accepted Answer

Answer reason: It contains the body’s thermoregulatory “set point” and integrates input from central and peripheral thermoreceptors. It coordinates autonomic and behavioral responses such as sweating and cutaneous vasodilation for heat loss, and shivering and vasoconstriction for heat conservation. The thalamus primarily relays sensory information, the cerebellum coordinates movement, and the medulla controls vital cardiorespiratory reflexes rather than temperature homeostasis.
Category reason: This is a foundational question about physiologic homeostasis (thermoregulation) and the function of specific brain regions, which fits Physiology rather than nursing care decision-making.

Question 43

Pulse oximeter is used to measure?

Accepted Answer

Answer reason: A pulse oximeter uses spectrophotometry to estimate peripheral arterial oxygen saturation (SpO2) by comparing absorption of red and infrared light in pulsatile blood flow. The device also detects the pulse waveform, allowing it to calculate heart rate from the pulsations. While accuracy can be reduced by poor perfusion, motion artifact, nail polish, or dyshemoglobins, its intended outputs are SpO2 and pulse rate.
Category reason: This question tests foundational knowledge of what a monitoring device measures (SpO2 and heart rate), which is a physiologic concept rather than a nursing-priority or intervention decision.

Question 44

The refractory period of cardiac muscle prevents:

Accepted Answer

Answer reason: Cardiac myocytes have a long absolute refractory period that overlaps most of the contraction due to the plateau phase of the action potential. This prevents summation of contractions, so the myocardium cannot be driven into sustained spasm. Avoiding tetany is essential to allow diastolic relaxation and ventricular filling between beats. In contrast, arrhythmias and premature depolarizations can still occur if excitability and conduction are abnormal.
Category reason: This question tests the physiological property of cardiac muscle action potentials (refractory period) and its functional consequence, which is foundational Physiology rather than a nursing intervention or safety decision.

Question 45

Which one of the following human organs can regenerates itself?

Accepted Answer

Answer reason: The liver has a unique capacity for compensatory hyperplasia, allowing restoration of functional mass after partial surgical removal or injury. Hepatocytes re-enter the cell cycle and proliferate in response to growth factors and cytokine signaling, rebuilding tissue architecture and function. In contrast, the kidney has limited regenerative ability (mainly tubular repair) and cannot reliably restore lost nephrons, and the spleen and stomach do not regenerate organ mass in the same robust way.
Category reason: This question tests foundational knowledge of organ regenerative capacity and tissue repair mechanisms, which is a physiology concept rather than a nursing care decision.

Question 46

The following are the essential requirements for efficient haemostasis except?

Accepted Answer

Answer reason: Efficient haemostasis depends on an intact coagulation cascade, which requires multiple clotting factors and calcium as a key cofactor in several activation steps. Vitamin K is essential for hepatic gamma-carboxylation and functional activity of factors II, VII, IX, and X (and proteins C and S). Intrinsic factor, however, is a gastric glycoprotein required for vitamin B12 absorption in the ileum and is not part of the coagulation process.
Category reason: This item tests foundational knowledge of the physiologic requirements for blood coagulation and haemostasis rather than nursing interventions or prioritization, so it fits Physiology within NursingScience.

Question 47

Which of the following does not manufacturer Digestive juices?

Accepted Answer

Answer reason: Digestive juices are secretions that aid digestion in the gastrointestinal tract, such as gastric juice from the stomach, pancreatic juice from the pancreas, and bile produced by the liver. The kidney’s primary roles are filtration of blood, regulation of fluid/electrolyte and acid-base balance, and urine formation. It is not part of the digestive system’s exocrine secretory organs and does not produce digestive secretions.
Category reason: This question tests knowledge of which organs physiologically produce digestive secretions, making it a foundational body-function question best classified under Physiology.

Question 48

Oxygen is transported in blood mainly by?

Accepted Answer

Answer reason: Most oxygen in blood is carried bound to hemoglobin within red blood cells, which provides a high-capacity transport mechanism. Only a small fraction of oxygen is dissolved directly in plasma, contributing minimally to total oxygen content. Platelets (thrombocytes) function primarily in hemostasis, and leukocytes are involved in immune defense rather than gas transport.
Category reason: This question tests the physiological mechanism of oxygen transport in blood, which is a core concept of human physiology rather than a nursing intervention or safety decision.

Question 49

Which component of the blood is primarily responsible for transport oxygen throughout the body?

Accepted Answer

Answer reason: They contain hemoglobin, which binds oxygen in the lungs and releases it to tissues based on local oxygen demand and gradients. White blood cells primarily function in immune defense, and platelets are key for hemostasis and clot formation. Plasma transports many solutes (e.g., nutrients, hormones) and a small amount of dissolved oxygen, but the vast majority of oxygen is carried bound to hemoglobin within erythrocytes.
Category reason: This is a foundational question about the physiologic role of blood components in oxygen transport, not a nursing intervention or clinical prioritization task.

Question 50

Which is not a function of the cerebrospinal fluid (CSF)?

Accepted Answer

Answer reason: CSF normally helps maintain a stable intracranial environment and provides buoyancy, shock absorption, and metabolic waste clearance rather than raising intracranial pressure. Increased intracranial pressure occurs pathologically when CSF production/absorption or flow is disrupted (e.g., hydrocephalus), not as a normal function. Protective cushioning and contributing to nutrient transport are recognized supportive roles of CSF.
Category reason: This is a foundational question about the normal roles of cerebrospinal fluid in maintaining central nervous system homeostasis, which is primarily studied in physiology rather than nursing intervention or safety decision-making.

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