Question 1

Which brain structures regulate sleep and wakefulness?

Accepted Answer

Answer reason: Sleep–wake regulation depends on interacting brainstem networks that control cortical arousal and synchronization. The reticular activating system in the brainstem promotes wakefulness by activating thalamocortical pathways and maintaining alertness. In contrast, bulbar (lower brainstem) synchronizing regions participate in promoting sleep by reducing arousal and facilitating synchronized, sleep-like cortical activity. Options centered on cortex or thalamus/hypothalamus alone miss the key brainstem arousal–sleep circuitry that directly toggles wakefulness versus sleep.

Question 2

When hypertension occurs, which responses by the kidneys help normalize blood pressure?

Accepted Answer

Answer reason: Renal regulation of blood pressure relies on pressure natriuresis/diuresis: when arterial pressure rises, the kidneys increase sodium and water excretion to reduce extracellular fluid volume. Lower intravascular volume decreases venous return and cardiac output, bringing blood pressure down toward normal. This response also counteracts RAAS activity, which would otherwise promote sodium and water retention and worsen hypertension. Options that retain sodium and/or water would expand volume and generally increase blood pressure rather than normalize it.

Question 3

The difference between simple diffusion and facilitated diffusion is that facilitated diffusion?

Accepted Answer

Answer reason: Facilitated diffusion is a type of passive transport that moves substances down their concentration gradient but needs a membrane carrier or channel to permit passage. Simple diffusion also moves down the gradient, but molecules cross directly through the lipid bilayer without a protein, typically if they are small and nonpolar. Both processes do not use ATP, so energy requirement does not distinguish them. Movement from low to high concentration would describe active transport, not facilitated diffusion.

Question 4

A client has just given birth at 42 weeks’ gestation. When assessing the neonate, which physical finding is expected by the nurse?

Accepted Answer

Answer reason: This peeling (desquamation) is a classic physical finding in neonates delivered after 42 weeks. In contrast, lanugo and abundant vernix are more typical of earlier gestational ages and tend to diminish as gestation advances. Lethargy is not an expected normal physical characteristic of post-term status and would prompt assessment for complications such as hypoglycemia or illness.

Question 5

A client is receiving nutritional counseling following an application of a plaster cast for a fracture. The client asks the nurse why vitamin D intake is important. What is the best response by the nurse?

Accepted Answer

Answer reason: During fracture healing, adequate availability of these minerals is essential for callus formation and remodeling. Options describing excretion are opposite of vitamin D’s physiologic effect, since it promotes retention and availability of calcium/phosphate rather than elimination. Potassium is not the primary mineral regulated by vitamin D in the context of bone repair, making that distractor less relevant.

Question 6

Within the understanding of pain control, nociceptors present in the body play an important role. What is this role?

Accepted Answer

Answer reason: Nociception is the physiologic process of detecting noxious (potentially tissue-damaging) stimuli and transmitting that signal to the CNS. These specialized sensory nerve endings (free nerve endings) transduce mechanical, thermal, or chemical injury into action potentials that are perceived as pain. Options describing them as medications, neurotransmitters, or relaxation mechanisms confuse receptors with pharmacologic agents or downstream modulation. Therefore, defining them as pain-sensitive nerve endings best matches their role in pain physiology.

Question 7

The nurse suspects that a client is experiencing metabolic alkalosis based on laboratory and physical findings. Which findings best validate this condition?

Accepted Answer

Answer reason: A pH of 7.51, HCO3 − of 29 mEq/L; muscle cramps and confusion Metabolic alkalosis is characterized by an elevated arterial pH with a primary increase in bicarbonate due to excess base or loss of acid. This option shows alkalemia (pH 7.51) with increased HCO3− (29 mEq/L), matching the defining lab pattern. Neuromuscular irritability (e.g., cramps) and altered mentation can occur because alkalosis increases calcium binding to albumin, reducing ionized calcium and contributing to paresthesias/cramps and confusion. In contrast, options with low pH indicate acidemia, which rules out alkalosis despite any bicarbonate changes.

Question 8

Which of the following statements is correct about passive diffusion?

Accepted Answer

Answer reason: Passive transport is defined by movement driven by an existing concentration (or electrochemical) gradient without cellular ATP expenditure. Molecules therefore move from higher to lower concentration, and when they cannot cross the lipid bilayer efficiently, they can still move passively via facilitated diffusion through channels or carriers. This makes the “may require a transport protein” clause accurate while preserving the key requirement of moving down the gradient. Options claiming energy use or movement up the gradient describe active transport, not passive diffusion.

Question 9

The blood contains ?

Accepted Answer

Answer reason: Whole blood water content is lower than plasma alone because red cells and plasma proteins contribute substantial non-water mass. An approximate value near four-fifths is commonly taught for whole blood, aligning with typical physiology reference ranges. Values like 95% more closely describe plasma water content rather than the entire blood volume, while 60% is too low for normal circulating blood.

Question 10

Calcium has an inverse relationship with which electrolyte?

Accepted Answer

Answer reason: When phosphate rises, more calcium binds with it and the free (ionized) calcium level can fall, contributing to hypocalcemia. Parathyroid hormone increases serum calcium while promoting renal phosphate excretion, further reinforcing this inverse relationship. Potassium is regulated primarily by insulin/acid-base status and renal handling and does not show a consistent inverse pairing with calcium. Magnesium more commonly shows a direct clinical association with calcium because low magnesium can impair PTH release and lead to low calcium rather than an inverse tracking pattern.

Question 11

Actions of Angiotensin II?

Accepted Answer

Answer reason: Angiotensin II is a core effector of the renin–angiotensin–aldosterone system that acutely increases arterial pressure by increasing systemic vascular resistance. Direct constriction of arteriolar smooth muscle produces a rapid rise in blood pressure even before slower volume-mediated mechanisms take effect. The other listed effects (aldosterone release, ADH release, and thirst stimulation) are also real but primarily support longer-term blood pressure control via sodium/water retention and increased intake. When forced to choose a single “best” action, the immediate, primary physiologic effect is vasoconstriction.

Question 12

What is the enzyme that breaks down the lactose?

Accepted Answer

Answer reason: The specific disaccharidase responsible for this reaction is produced by enterocytes in the small intestine, so deficiency leads to malabsorption with osmotic diarrhea, bloating, and gas. Amylase targets starch (polysaccharides), pepsin digests proteins in the stomach, and lipase digests triglycerides, so these do not directly cleave lactose. Therefore the enzyme needed to break down lactose is the brush-border disaccharidase for lactose.

Question 13

The nurse provides care for a patient with lactic acidosis following prolonged cardiopulmonary resuscitation (CPR). Which arterial blood gas (ABG) result does the nurse anticipate for this client?

Accepted Answer

Answer reason:  Lactic acidosis is a primary metabolic acidosis caused by tissue hypoperfusion and anaerobic metabolism, which lowers serum bicarbonate and decreases pH. The expected ABG pattern is acidemia with a reduced HCO3−, along with respiratory compensation via hyperventilation producing a low PaCO2. Prolonged CPR and poor perfusion commonly generate elevated lactate, making this metabolic picture most likely. A common distractor is respiratory acidosis (high PaCO2) which would fit hypoventilation rather than lactate-driven metabolic derangement.

Question 14

The nurse is receiving report on a patient who has experienced EKG changes overnight. Peaked T waves are present and the PR interval is elongated. The nurse should suspect?

Accepted Answer

Answer reason: Early hyperkalemia classically causes tall, peaked T waves, and as potassium rises it can also slow AV nodal conduction, leading to PR prolongation. This pairing is most consistent with hyperkalemia compared with the other electrolyte options listed. Hypocalcemia more typically prolongs the QT interval, while hypernatremia does not have a hallmark pattern of peaked T waves on ECG.

Question 15

Which of the following statements about the role of the neurons in controlling the muscles is correct?

Accepted Answer

Answer reason: In contrast, sensory (afferent) neurons carry information from peripheral receptors (including muscle spindles and skin receptors) toward the spinal cord/brain. Therefore the statement describing flow from spinal cord to muscle matches the direction and function of motor neurons. A common trap is reversing afferent vs efferent pathways; information from muscle back to spinal cord is sensory feedback, not motor output.

Question 16

Test perception of a baby develops at?

Accepted Answer

Answer reason: Around 6 months, infants typically begin complementary feeding, and taste responsiveness is notably more developed and observable because exposure to varied flavors increases. This timing aligns with developmental maturation of sensory pathways and feeding behaviors, making it the best single choice among the options. Earlier options can be misleading because they reflect basic taste capability rather than a more developed, clinically observable taste perception.

Question 17

Normal head circumference of new born at birth ranges from?

Accepted Answer

Answer reason: This measurement reflects typical brain and skull growth at birth and is used to screen for microcephaly or macrocephaly. Ranges centered in the low 30s are generally too small for a term infant and would raise concern for microcephaly or measurement error. A range extending to 38 cm overestimates normal for most term newborns and would more often suggest macrocephaly or molding-related variation requiring follow-up.

Question 18

A nurse administers an intravenous solution of 0.45% sodium chloride. In what category of fluids does this solution belong?

Accepted Answer

Answer reason: 0.45% sodium chloride (“half-normal saline”) has a lower osmolality than plasma, so it acts as a hypotonic fluid in the body. This causes water to shift from the extracellular space into cells, expanding intracellular volume. By contrast, isotonic solutions (e.g., 0.9% saline, LR) stay primarily in the extracellular compartment and do not drive net water into cells.

Question 19

What clinical finding indicates to a nurse that a client may have hypokalemia?

Accepted Answer

Answer reason: This can present clinically as constipation, hypoactive bowel sounds, and abdominal bloating/distention. Muscle spasms are more classically associated with hypocalcemia (tetany) rather than low potassium, which more often causes muscle weakness and cramps. Kussmaul breathing reflects metabolic acidosis (e.g., DKA), not a primary sign of hypokalemia, and edema is more consistent with fluid overload states.

Question 20

A client who was attacked by a vicious dog has reacted accordingly, activating General Adaptation Syndrome and the fight or flight response sets in. Which is not a response by the client in relation to the situation?

Accepted Answer

Answer reason: Fight-or-flight is mediated by sympathetic activation, which shunts blood to skeletal muscle and increases adrenergic effects to enhance rapid response. Sympathetic stimulation decreases salivary and other GI secretions, often causing dry mouth rather than increased saliva. It also causes peripheral vasoconstriction leading to cool, pale skin and triggers sweating via sympathetic cholinergic fibers. Pupillary dilation is another classic adrenergic response that improves visual acuity in acute threat.

Question 21

Which part of the nervous system is primarily involved in controlling involuntary actions, like heart rate and digestion?

Accepted Answer

Answer reason: The autonomic division provides sympathetic and parasympathetic outflow to cardiac muscle and the gastrointestinal tract, adjusting heart rate, vascular tone, and motility/secretions. By contrast, the somatic system primarily controls voluntary skeletal muscle movement. While the CNS and PNS are broader anatomic divisions, they are not the specific functional branch dedicated to involuntary organ regulation.

Question 22

The patient has positive Chvostek’s and Trousseau’s signs. The nurse knows this is indicative of which deficiency?

Accepted Answer

Answer reason: Facial nerve tapping causing facial twitching and BP cuff inflation provoking carpopedal spasm are classic bedside indicators of low ionized calcium. This pattern most directly matches calcium deficiency rather than iron deficiency, which presents with anemia-related symptoms. Although hypomagnesemia can contribute to hypocalcemia by impairing PTH release/action, the hallmark association tested with these signs is hypocalcemia.

Question 23

A Physiological risk associated with prolonged immobility is?

Accepted Answer

Answer reason: With less venous return and reduced demand for increased cardiac output, the heart does less work acutely, but this contributes to orthostatic intolerance and diminished exercise tolerance when activity resumes. A common distractor is altered calcium balance: immobility tends to increase bone resorption (not decrease it), which can raise serum calcium and promote renal calculi. Hemoglobin production is not increased; instead, plasma volume shifts and deconditioning can contribute to reduced tolerance to activity rather than enhanced oxygen-carrying capacity.

Question 24

Which organ stores iron and vitamin A,D,B12?

Accepted Answer

Answer reason: It stores iron primarily as ferritin/hemosiderin and serves as the main reservoir for vitamin A, with clinically important stores of vitamin B12 as well. It also stores vitamin D (as 25-hydroxyvitamin D and related metabolites) contributing to systemic availability. By contrast, the spleen is mainly involved in filtering blood and recycling iron from aged RBCs rather than serving as the primary storage organ for this combination of vitamins and iron.

Question 25

Which of the following vital signs is likely to be lower in a child than in an adult?

Accepted Answer

Answer reason: In contrast, heart rate and respiratory rate are typically higher in children to maintain cardiac output and meet metabolic demand. Oxygen saturation (pulse oximetry) should be similar across ages in healthy individuals, usually in the mid-to-high 90s. Therefore, among the listed vital signs, blood pressure is the one expected to be lower in children than adults.

Question 26

Lack of intrinsic factor in the gastric mucosa impairs absorption of which vitamin?

Accepted Answer

Answer reason: When intrinsic factor is absent (e.g., pernicious anemia, post-gastrectomy), cobalamin cannot be efficiently absorbed, leading to megaloblastic anemia and potential neurologic deficits. The other listed vitamins do not depend on intrinsic factor for intestinal uptake. This is why intrinsic factor deficiency classically presents with low cobalamin despite adequate dietary intake.

Question 27

Which of the following is not a finding associated with fluid volume excess?

Accepted Answer

Answer reason: Cardiovascular compensation to increased preload/volume overload can manifest with tachycardia, especially if cardiac output is strained. Thirst is classically driven by hyperosmolality and/or hypovolemia (as in dehydration), not by volume overload where dilutional effects tend to reduce osmotic thirst drive. Therefore thirst is least consistent with fluid volume excess compared with the other listed findings.

Question 28

Respiratory effort absent scores—?

Accepted Answer

Answer reason: When respirations are absent (apnea), the newborn receives a score of 0 for the respiration component. A score of 1 corresponds to slow or irregular breathing, and 2 corresponds to a good cry with regular respirations. This item tests correct recall/application of the standardized physiologic scoring rubric used immediately after birth.

Question 29

The main enzyme in saliva?

Accepted Answer

Answer reason: This function is performed by salivary amylase (ptyalin), making it the primary enzymatic component of saliva for digestion. Trypsin is a pancreatic protease active in the small intestine, and pepsin is a gastric protease active in the stomach’s acidic environment. While a lingual lipase exists, it is not considered the main salivary enzyme in standard physiology teaching compared with amylase.

Question 30

Least generative power is a feature of which among the following cells of Human Body?

Accepted Answer

Answer reason: Neurons in the central nervous system are classically considered permanent cells; damage is largely irreversible and healing occurs mainly via gliosis rather than true neuron replacement. In contrast, skin and liver are labile/stable tissues with robust regenerative potential, and bone has ongoing remodeling via osteoblast and osteoclast activity. Therefore, among the options, neural tissue best represents the least generative power.

Question 31

Which of the following gastrointestinal changes is likely to be present in the older adult?

Accepted Answer

Answer reason: This directly explains why older adults often report blunted taste and may add extra salt or sugar to foods. Increased thirst is not typical because thirst sensation often decreases with aging, raising dehydration risk. A stronger gag reflex is also not expected; protective reflexes like gag and swallow coordination can be diminished, increasing aspiration risk.

Question 32

Which electrolyte has a significant impact on the cardiac muscle and can result in dysrhythmias when it is elevated or low?

Accepted Answer

Answer reason: Hyperkalemia slows conduction and can produce peaked T waves, PR prolongation, QRS widening, and malignant ventricular dysrhythmias/asystole. Hypokalemia increases myocardial excitability and prolongs repolarization, predisposing to ectopy and potentially torsades/ventricular arrhythmias, especially with digoxin or other QT-prolonging risks. While calcium and magnesium also affect rhythm, potassium abnormalities are the classic and most directly linked electrolyte cause of dysrhythmias in both high and low states.

Question 33

During which stage of sleep does vivid dreaming occur?

Accepted Answer

Answer reason: REM is also characterized by rapid eye movements and increased autonomic variability, matching the physiologic state associated with complex dreams. In contrast, NREM stages I–III are dominated by progressively slower brain waves and are more associated with light sleep, sleep spindles/K complexes, and deep slow-wave restorative sleep rather than vivid dream recall. Therefore, the stage most linked to vivid dreaming is REM.

Question 34

Which of the following is considered fully compensated?

Accepted Answer

Answer reason: In a fully compensated state, the non-primary parameter (either CO2 for metabolic problems or HCO3 for respiratory problems) shifts in the opposite direction enough to normalize pH. Because both CO2 and HCO3 remain abnormal, it indicates ongoing compensation rather than resolution of the underlying issue. If pH is still abnormal, compensation is only partial (or uncompensated), even if one or both other values have started to change.

Question 35

What is the main function of the sarcoplasmic reticulum in muscle cells?

Accepted Answer

Answer reason: The sarcoplasmic reticulum serves as the primary intracellular calcium reservoir, releasing Ca2+ to initiate contraction and re-sequestering it via SERCA pumps to allow relaxation. This role directly supports excitation–contraction coupling in skeletal and cardiac muscle. By contrast, ATP production is mainly a mitochondrial function, and protein synthesis occurs at ribosomes/rough ER rather than the specialized sarcoplasmic reticulum.

Question 36

The major source of vitamin D is?

Accepted Answer

Answer reason: Vitamin D is primarily synthesized endogenously in the skin when UVB radiation converts 7-dehydrocholesterol to cholecalciferol (vitamin D3). Dietary sources contribute, but for most people they are a smaller component compared with cutaneous production under adequate sun exposure. Fruits generally contain negligible vitamin D. Dairy and meats can provide some vitamin D (often via fortification or specific foods like fatty fish), so limiting to “milk only” or “meat only” is not accurate as the major source.

Question 37

The chief anion in the intracellular fluid (ICF) is?

Accepted Answer

Answer reason: Phosphate ions buffer intracellular pH and participate in energy metabolism (ATP) and cellular signaling, making them a dominant negatively charged species inside cells. Chloride and sodium are primarily extracellular ions and therefore are not the chief intracellular anion. Potassium is the chief intracellular cation, so it cannot be the correct anion choice.

Question 38

What is a normal respiratory rate for a healthy newborn?

Accepted Answer

Answer reason: Newborns have higher oxygen demand and smaller functional residual capacity, so they normally breathe faster than older children and adults. A resting neonatal respiratory rate around 30–60/min is expected when the infant is quiet and not crying. Rates like 12–20/min correspond to adults, and 20–40/min is more typical of older infants/children rather than a neonate.

Question 39

Hypertonic fluids cause?

Accepted Answer

Answer reason: In a hypertonic extracellular fluid, the solute concentration outside the cell is higher than inside, so water leaves the cell. Loss of intracellular water reduces cell volume, producing crenation/shrinkage. By contrast, a hypotonic solution would drive water into cells causing swelling and potentially hemolysis in red blood cells.

Question 40

Bilirubin is excreted mainly through—?

Accepted Answer

Answer reason: In the gut it is converted to urobilinogen and then stercobilin, giving stool its brown color, so the dominant elimination pathway is via stool. Only a small fraction of urobilinogen is reabsorbed and ultimately excreted by the kidneys, which is why urine is not the main route for bilirubin disposal in normal physiology. When bile flow is obstructed, stool can become pale and urinary bilirubin can rise, highlighting that fecal excretion is normally primary.

Question 41

Which IV fluid is isotonic?

Accepted Answer

Answer reason: 0.9% Normal Saline Tonicity describes a solution’s effective osmolality relative to plasma and predicts the direction of water movement across cell membranes. 0.9% sodium chloride has an osmolality close to plasma, so it primarily expands the extracellular fluid space without causing significant net fluid shifts into or out of cells. In contrast, 0.45% saline is hypotonic and promotes water movement into cells. D10W is hypertonic, and although D5W is initially isotonic in the bag, it becomes effectively hypotonic after dextrose is metabolized, so it is not the best answer for an “isotonic” IV fluid in practice.

Question 42

Pink body and blue extremities, pulse 120 bpm, weak cry scores?

Accepted Answer

Answer reason: Pink trunk with blue extremities indicates acrocyanosis, which scores 1 for Appearance. A pulse of 120 bpm scores 2 for Pulse, and a weak cry indicates some respiratory effort, which scores 1 for Respiration; the remaining typical implied normal findings (good reflex response and some flexion/movement) contribute 2 and 1 respectively to reach a total of 9. A perfect 10 would require completely pink coloration and a strong cry, while 7–8 would imply additional deficits beyond acrocyanosis and weak cry.

Question 43

A patient with edema has?

Accepted Answer

Answer reason: Mechanisms include increased hydrostatic pressure (e.g., heart failure), decreased oncotic pressure (e.g., hypoalbuminemia), increased capillary permeability, or lymphatic obstruction—all of which promote fluid movement out of the vasculature. While electrolyte abnormalities can coexist, they are not the defining feature of edema. Protein loss can contribute by lowering plasma oncotic pressure, but edema is not due to protein loss alone and still represents excess interstitial fluid.

Question 44

The type of fluid used to manipulate fluid shifts among compartments states is?

Accepted Answer

Answer reason: Colloids increase plasma oncotic pressure, which pulls water into the intravascular space from the interstitium, thereby “manipulating” compartment shifts. This makes the listed colloid the best choice among the options. Whole blood mainly replaces oxygen-carrying capacity and volume but is not used primarily to create oncotic-driven shifts; TPN and oral supplements address nutrition rather than acute compartment fluid movement.

Question 45

Bicarbonate is lost during which of the following clinical conditions?

Accepted Answer

Answer reason: With diarrhea, especially large-volume or lower-GI losses, this bicarbonate-rich fluid is lost in stool, leading to a tendency toward normal anion gap (hyperchloremic) metabolic acidosis. Vomiting more typically causes loss of gastric hydrochloric acid, producing metabolic alkalosis rather than bicarbonate loss. Diaphoresis primarily causes water and sodium losses, and diuresis does not inherently imply bicarbonate loss unless specific renal tubular processes or drugs are involved.

Question 46

A client’s blood gases reflect diabetic acidosis. The nurse should expect?

Accepted Answer

Answer reason: In metabolic acidosis, the hallmark ABG change is a reduced serum bicarbonate level, with pH trending low rather than high. Respiratory compensation is hyperventilation (Kussmaul respirations) which lowers PaCO2, making an increased PCO2 a poor fit. Oxygenation (PaO2) is not the defining abnormality of DKA-related acid–base disturbance and may be normal unless there is concurrent respiratory pathology.

Question 47

Body fluids perform which of the following functions?

Accepted Answer

Answer reason: Dissolved glucose, amino acids, vitamins, and other solutes are carried from sites of absorption or storage to tissues for cellular use. While ions in body fluids do help conduct electrical activity, the question asks for a single best general function, and nutrient transport is the most fundamental and broadly applicable. Fat metabolism is primarily an intracellular/organ-level biochemical process rather than a direct function of body fluid itself.

Question 48

Normal heart rate of a neonate at rest?

Accepted Answer

Answer reason: A typical resting range for a newborn is approximately 100–160 beats per minute, and brief increases may occur with crying or activity. Values like 60–80 bpm are more consistent with bradycardia in a neonate and would prompt assessment of oxygenation, temperature, and perfusion. A sustained rate in the 160–200 bpm range is more suggestive of tachycardia from fever, pain, hypovolemia, or supraventricular tachycardia rather than normal rest.

Question 49

When assessing a patient’s total body water percentage, the nurse is aware that all of the following factors influence this except?

Accepted Answer

Answer reason: With increasing age, TBW percentage decreases due to higher relative fat mass and lower muscle mass. Males typically have a higher TBW percentage than females because they generally have more lean tissue. Muscle mass increases TBW because skeletal muscle contains substantially more water than adipose tissue, so variations in muscle strongly affect TBW estimates.

Question 50

Mr. Wenceslao is scheduled to receive an isotonic solution; which one of the following is an example of such a solution?

Accepted Answer

Answer reason: Isotonic IV fluids have an osmolality similar to plasma, so they expand the extracellular/intravascular space without causing major shifts of water into or out of cells. 0.9% sodium chloride (normal saline) is the standard isotonic crystalloid used for volume replacement and maintenance. In contrast, 0.45% saline is hypotonic and can move water into cells, and 3% saline is hypertonic and draws water out of cells. D10W is hypertonic in the bag and is not considered an isotonic crystalloid for routine isotonic replacement.

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