Question 1

Toxic substances are detoxified in human body in?

Accepted Answer

Answer reason: The liver is the primary organ for detoxification, performing biotransformation of xenobiotics via phase I (cytochrome P450) and phase II conjugation reactions to make compounds more water‑soluble. The kidneys mainly excrete these metabolites rather than detoxify them. The lungs can eliminate volatile substances but are not the main site of detoxification, and the stomach is involved in digestion, not detoxification.

Question 2

How much salt is present in our body?

Accepted Answer

Answer reason: The salinity of human extracellular fluid is approximately equivalent to 0.9% sodium chloride, which is considered isotonic (normal saline). Many general references round this to about 1% salt content when describing the body’s overall salinity. Among the given options, 1% is the closest and best answer.

Question 3

Which organ is called the balancing organ?

Accepted Answer

Answer reason: Balance is primarily mediated by the vestibular apparatus in the inner ear, which includes the semicircular canals and the otolith organs (utricle and saccule). These structures detect angular and linear acceleration and send signals to the brain to maintain posture and equilibrium. While the brain integrates the information and the eyes contribute, the ear is the organ specifically responsible for balance.

Question 4

Glucose stored in ...?

Accepted Answer

Answer reason: The body stores excess glucose primarily in the liver as glycogen, which can be broken down to maintain blood glucose during fasting. Kidneys mainly reabsorb filtered glucose and do not store it. The pancreas regulates glucose via insulin and glucagon secretion rather than storage. Nephrons are renal functional units and are not sites of glucose storage.

Question 5

What is the normal body temperature of a healthy human?

Accepted Answer

Answer reason: The average normal core body temperature in healthy adults is approximately 37°C, with a typical range of about 36.5–37.5°C depending on site and circadian variation. A value of 35°C suggests hypothermia, while 38°C is consistent with fever. Therefore, 37°C is the best single answer representing normal.

Question 6

Which of the following descriptions best defines general adaptation syndrome?

Accepted Answer

Answer reason: General adaptation syndrome (GAS), described by Selye, is the body's nonspecific physiological response to any stressor across the stages of alarm, resistance, and exhaustion. It encompasses both acute and chronic responses mediated by the sympathetic-adrenal-medullary and HPA axes. The other options describe fear/avoidance behavior, memory-related hippocampal arousal, or a psychiatric outcome (depression), none of which define GAS.

Question 7

Which part of the body continues to grow throughout life?

Accepted Answer

Answer reason: The nose and ears contain elastic cartilage and connective tissue that demonstrate appositional growth and age-related changes in collagen, making them enlarge over time. Gravity and tissue laxity also contribute to their apparent increase in size with aging. In contrast, long bones stop growing after epiphyseal plate closure, brain size stabilizes after adolescence, and teeth do not continue to grow (though they may slowly erupt with wear).

Question 8

The pH of human blood is?

Accepted Answer

Answer reason: Normal arterial blood pH is tightly regulated between 7.35 and 7.45 by the bicarbonate buffer system, lungs (CO2 excretion), and kidneys (H+ secretion and HCO3− reabsorption). Values below this range indicate acidemia and above indicate alkalemia, both of which can impair cellular function and enzyme activity. The other ranges listed are outside the physiologically normal limits for healthy human blood.

Question 9

A patient with liver failure is most likely to have low levels of?

Accepted Answer

Answer reason: In liver failure, the urea cycle is impaired, so ammonia is not efficiently converted to urea, resulting in a low blood urea nitrogen (BUN). Ammonia levels tend to be elevated, not low. Creatinine is primarily a marker of renal function and is not decreased by hepatic failure alone. Chloride levels are generally unaffected by isolated liver dysfunction.

Question 10

A patient is admitted to the emergency department with hypoventilation and decreased respiratory rate after an opioid overdose. Arterial blood gas analysis reveals a pH of 7.29, PaCO2 of 60 mmHg, and HCO3- of 28 mEq/L. Which of the following compensatory mechanisms is expected in this patient?

Accepted Answer

Answer reason: The ABG shows respiratory acidosis (low pH with elevated PaCO2) from hypoventilation due to opioid overdose. The immediate physiologic response that helps correct hypercapnia is an increase in ventilation to blow off CO2, raising pH toward normal. Options b, c, and d would all worsen acidosis—reducing ventilation or losing bicarbonate buffering or retaining hydrogen ions. Renal compensation also involves bicarbonate retention and increased H+ excretion, consistent with the slightly elevated HCO3−.

Question 11

Which of following called the powerhouse of cell?

Accepted Answer

Answer reason: Mitochondria generate most of the cell’s ATP through oxidative phosphorylation, so they are termed the powerhouse of the cell. Vesicles primarily transport and store substances. The nucleus houses genetic material and controls gene expression. The Golgi apparatus modifies, sorts, and packages proteins and lipids for trafficking.

Question 12

Foremilk is rich in?

Accepted Answer

Answer reason: Foremilk, the milk released at the start of a feed, is thin and high in water and lactose to satisfy the infant’s thirst. It is comparatively low in fat, which increases later in the feeding as hindmilk is expressed. Protein content is relatively stable and not particularly high in foremilk, and calcium levels are not a distinguishing feature. Therefore, foremilk is rich in water.

Question 13

The process of fusion of male and female gametes in plants is called?

Accepted Answer

Answer reason: Syngamy specifically refers to the fusion of male and female gametes to form a zygote, which is the core event of fertilization in plants. Pollination is only the transfer of pollen to the stigma and does not involve gamete fusion. Conjugation refers to genetic exchange in certain microbes/algae and is not the standard term for plant gamete fusion. Therefore, the most precise term for gamete fusion is syngamy.

Question 14

Which of the following is a sign of dehydration?

Accepted Answer

Answer reason: Dehydration reduces total body water and extracellular fluid volume, leading to decreased salivary secretions and a classic finding of dry mucous membranes. In dehydration, the body conserves fluid via ADH and renal mechanisms, typically causing decreased urine output rather than increased. Heart rate more commonly increases (tachycardia) as a compensatory response to hypovolemia, not decreases. Appetite is not a reliable hallmark sign compared with mucosal dryness and thirst.

Question 15

The main function of blood is to transport ____ and ____ to tissues?

Accepted Answer

Answer reason: A primary physiological role of blood is transport: red blood cells carry oxygen (bound to hemoglobin) to body tissues, and plasma carries nutrients (e.g., glucose, amino acids, lipids) to cells for metabolism. This transport supports cellular respiration and energy production. The other choices list body structures (hair, nails, skin, fat) or incomplete/less accurate framing of what blood primarily delivers (water and sugar alone).

Question 16

In human body urea is synthesized by?

Accepted Answer

Answer reason: Urea is synthesized in the liver via the urea (ornithine) cycle, which converts toxic ammonia produced from amino acid metabolism into urea for safer transport in blood. The kidneys primarily excrete urea in urine but do not synthesize it. The gallbladder stores bile and the heart has no role in urea production.

Question 17

Hypothermia in preterm babies occurs due to?

Accepted Answer

Answer reason: Preterm infants are prone to hypothermia because they have reduced brown adipose tissue, limiting non-shivering thermogenesis. Their skin is thin and more permeable with less subcutaneous fat, increasing heat loss through evaporation and conduction. They also have a relatively large surface-area-to-body-mass ratio, which accelerates radiant and convective heat loss. Therefore, all listed factors contribute.

Question 18

Generally biological activity is relatively little?

Accepted Answer

Answer reason: Most biological processes are enzyme-mediated and show minimal activity at very low temperatures because molecular motion and enzyme-substrate collisions are greatly reduced. At higher temperatures, many enzymes and proteins begin to denature, leading to loss of function and thus reduced biological activity; a commonly taught general threshold is around >50°C for many organisms and tissues. Therefore, biological activity is relatively little below 0°C or above 50°C compared with the normal physiologic range. The other options use temperature cutoffs that are less consistent with general enzyme/biologic activity limits.

Question 19

Which type of muscle is involved in peristalsis?

Accepted Answer

Answer reason: Peristalsis is an involuntary, rhythmic wave of contraction that propels contents through the gastrointestinal tract. This movement is produced by smooth muscle in the walls of the esophagus, stomach, and intestines under autonomic and enteric nervous system control. Cardiac muscle is confined to the heart, skeletal muscle is primarily voluntary movement, and “myofibril muscle” is not a recognized muscle type.

Question 20

Which of following has the highest protein content?

Accepted Answer

Answer reason: Plasma contains the highest protein concentration because it normally includes abundant circulating proteins such as albumin, globulins, and fibrinogen. Lymph is derived from interstitial fluid and generally has lower protein levels than plasma (though it varies by tissue). Synovial fluid is an ultrafiltrate of plasma with added hyaluronic acid and relatively low protein. CSF has very low protein due to the blood-brain barrier and selective transport.

Question 21

The first shunt to close after birth is?

Accepted Answer

Answer reason: After birth, the umbilical arteries constrict rapidly in response to increased oxygen tension and removal of placental circulation, functionally closing within minutes. This prevents blood loss from the newborn via the severed umbilical cord. The umbilical vein and ductus venosus close later (hours to days), and the foramen ovale closes functionally with rising left atrial pressure after lung expansion.

Question 22

Which plasma protein maintains colloid osmotic pressure?

Accepted Answer

Answer reason: Albumin is the most abundant plasma protein and is the primary contributor to plasma colloid (oncotic) pressure, helping retain water within the intravascular space. When albumin levels fall (e.g., liver disease, nephrotic syndrome), oncotic pressure decreases and fluid shifts into the interstitial space, causing edema/ascites. Fibrinogen and prothrombin are mainly involved in coagulation, and globulins primarily function in transport and immunity rather than maintaining oncotic pressure.

Question 23

Which organelle is responsible for protein modification, sorting, and packaging?

Accepted Answer

Answer reason: The Golgi apparatus receives proteins from the rough endoplasmic reticulum and performs post-translational modification (such as glycosylation), then sorts and packages these proteins into vesicles for secretion, membrane insertion, or delivery to other organelles.

Question 24

Lysosomes are produced by which of the following cell organelles?

Accepted Answer

Answer reason: Lysosomes are formed from vesicles that bud off the Golgi complex after it packages hydrolytic enzymes synthesized in the rough endoplasmic reticulum.

Question 25

Which enzyme digest plant proteins?

Accepted Answer

Answer reason: Erepsin refers to intestinal peptidases in the small intestine that complete protein digestion by breaking peptides into amino acids; these enzymes act on proteins from any dietary source, including plant proteins. Pepsin is the primary gastric protease but is not the classic answer for “plant proteins” in such MCQs. Renin (rennin/chymosin) is involved in milk (casein) coagulation in infants, not plant protein digestion. Therefore, erepsin is the best option among those listed.

Question 26

Normal pulse rate for a newborn is around?

Accepted Answer

Answer reason: A normal resting heart rate for a term newborn is typically about 120–160 beats per minute due to higher metabolic demand and lower stroke volume compared with older children and adults. Rates like 40–60/min suggest marked bradycardia, while 80–100/min is more consistent with older children/adults. A sustained rate of 180–200/min would be concerning for tachycardia and possible pathology (e.g., fever, dehydration, SVT) rather than normal baseline.

Question 27

Vibrating sound is transmitted by Tympanic membrane to one of the following structures?

Accepted Answer

Answer reason: The tympanic membrane (eardrum) vibrates in response to sound waves and transmits these mechanical vibrations directly to the ossicles, beginning with the malleus attached to the membrane. The ossicles (malleus, incus, stapes) amplify and conduct the vibrations to the oval window of the inner ear. The auditory meatus only conducts sound waves to the tympanic membrane, while the cochlea and vestibule are inner-ear structures that receive vibrations after ossicular transmission.

Question 28

What part of the brain controls breathing and heart rate?

Accepted Answer

Answer reason: The medulla oblongata contains vital autonomic centers that regulate respiration (respiratory rhythm generation) and cardiovascular function (heart rate and blood pressure control). These brainstem nuclei integrate input from chemoreceptors and baroreceptors to maintain homeostasis without conscious effort. The cerebrum and frontal lobe primarily manage higher cognitive and voluntary motor functions, while the cerebellum coordinates movement and balance rather than basic life-sustaining autonomic control.

Question 29

Normal fetal heart rate is?

Accepted Answer

Answer reason: The normal baseline fetal heart rate is typically 110–160 beats per minute, so the closest option is 120–160/min. Rates below this range suggest fetal bradycardia and can indicate hypoxia or conduction problems, while higher sustained rates suggest tachycardia (e.g., infection, maternal fever, medications). Therefore, 120–160/min best represents the normal fetal heart rate range among the choices.

Question 30

The element that helps in blood clotting?

Accepted Answer

Answer reason: Vitamin K is required for hepatic gamma-carboxylation of clotting factors II, VII, IX, and X as well as proteins C and S, enabling them to bind calcium and function in the coagulation cascade. Deficiency leads to impaired clot formation and an increased bleeding tendency. The other listed fat-soluble vitamins (A, D, E) do not directly support synthesis/activation of these coagulation factors, and vitamin E excess can actually increase bleeding risk.

Question 31

Sunlight is the best source of which vitamin?

Accepted Answer

Answer reason: Sunlight (UVB radiation) triggers conversion of 7-dehydrocholesterol in the skin to cholecalciferol (vitamin D3), making sun exposure a major natural source of vitamin D. Vitamins A, B-complex, and C must primarily be obtained from dietary sources rather than synthesized via sunlight. Vitamin D is then activated in the liver and kidneys to support calcium/phosphate homeostasis and bone health.

Question 32

Which vessel carries the least oxygenated blood in fetus?

Accepted Answer

Answer reason: In fetal circulation, the umbilical vein carries the most oxygenated blood from the placenta to the fetus. Blood returning from the fetus back to the placenta via the umbilical arteries has already delivered oxygen to fetal tissues and is therefore relatively deoxygenated. The inferior vena cava contains a mix of oxygenated blood (from ductus venosus) and deoxygenated blood (from lower body), so it is not the least oxygenated. The right atrium also contains mixed blood due to streaming and venous return, not the least oxygenated overall.

Question 33

The normal range for adult respiratory rate is?

Accepted Answer

Answer reason: Normal adult resting respiratory rate is typically taught as about 12–20 breaths per minute, and many nursing references accept 10–20 as a normal range for healthy adults at rest. The other choices extend the upper limit into tachypnea (>20) or are too narrow to represent the usual accepted range. Therefore, 10–20 breaths per minute is the best answer among the provided options.

Question 34

The spindle apparatus is formed during the -------- phase of mitosis?

Accepted Answer

Answer reason: The mitotic spindle begins to form during prophase as centrosomes migrate to opposite poles and microtubules polymerize to create the spindle framework. This setup is necessary before chromosomes can align at the metaphase plate. Metaphase is characterized by completed spindle attachment and alignment, anaphase by chromatid separation, and telophase by spindle breakdown and nuclear reformation.

Question 35

Glucose stored in ...?

Accepted Answer

Answer reason: Glucose is stored primarily as glycogen, with the liver serving as a major glycogen storage site that helps maintain blood glucose between meals. While skeletal muscle also stores glycogen, it is not offered as an option here. The pancreas regulates blood glucose via insulin and glucagon but is not a storage organ. Kidneys/nephrons handle filtration and glucose reabsorption rather than storing glucose.

Question 36

The organ that stores excess sugar than the body needs is?

Accepted Answer

Answer reason: The liver stores excess glucose by converting it to glycogen (glycogenesis) and can later release glucose through glycogenolysis to help maintain blood glucose levels. While muscle also stores glycogen, the classic single-organ answer for excess sugar storage and systemic glucose regulation is the liver. The pancreas primarily regulates blood glucose via insulin and glucagon secretion rather than storing sugar. The heart and stomach are not glucose storage organs.

Question 37

In man, Cardiac Cycle duration is?

Accepted Answer

Answer reason: At a normal resting heart rate of about 75 beats/min, one cardiac cycle takes approximately 60/75 ≈ 0.8 seconds. This duration encompasses atrial systole, ventricular systole, and the relaxation/filling phases. While the cardiac cycle shortens with tachycardia and lengthens with bradycardia, 0.8 seconds is the standard physiologic value for an average adult at rest.

Question 38

Which acid-base imbalance is most commonly associated with hyperventilation?

Accepted Answer

Answer reason: Hyperventilation increases alveolar ventilation and causes excessive CO2 to be blown off, lowering PaCO2. Because CO2 is an acid (via carbonic acid), the drop in PaCO2 raises blood pH, producing alkalemia. This is therefore a primary respiratory disturbance (not metabolic) and is best classified as respiratory alkalosis.

Question 39

Which electrolyte is crucial for cardiac function?

Accepted Answer

Answer reason: Potassium is the key intracellular electrolyte that determines the resting membrane potential of cardiac myocytes and strongly influences cardiac conduction and rhythm. Both hypokalemia and hyperkalemia can precipitate dangerous dysrhythmias and characteristic ECG changes. While calcium and magnesium also affect cardiac contractility and electrical stability, potassium is most directly crucial for maintaining normal cardiac electrical function.

Question 40

Total volume of blood in a normal human being is?

Accepted Answer

Answer reason: In a normal adult, total blood volume averages about 70 mL/kg, which is roughly 5 liters in a 70-kg person. Common teaching ranges place adult blood volume around 4.5–6 liters depending on body size and sex. Therefore, 5–6 liters is the best match among the options. The other ranges are either too low for most adults (3–4 L) or far above normal (8–10 L, 10–12 L).

Question 41

Which of the following is the respiratory organ in earthworms?

Accepted Answer

Answer reason: Earthworms do not have specialized respiratory organs like lungs, gills, or spiracles. They exchange oxygen and carbon dioxide by diffusion across their moist body surface (cutaneous respiration). Adequate moisture is essential because gases diffuse through a thin film of water on the skin. Therefore, the skin is the functional respiratory surface.

Question 42

The blood contains ?

Accepted Answer

Answer reason: Whole blood is composed of plasma and formed elements (RBCs, WBCs, platelets). Plasma is ~90–92% water, and because plasma makes up about 55% of blood volume, a common exam approximation is that blood contains about 80% water overall; however, among the provided options, 90% best matches the physiologic fact typically tested (plasma water content). The other choices (95% and 60%) are not consistent with standard physiologic composition values. Therefore, 90% is the best answer given the options.

Question 43

Which organ stores glycogen in the human body?

Accepted Answer

Answer reason: The liver is the primary organ for glycogen storage and plays a central role in maintaining blood glucose between meals through glycogenolysis and gluconeogenesis. While skeletal muscle also stores glycogen, it is used locally and does not directly release glucose into the bloodstream. The pancreas regulates glucose via hormones (insulin and glucagon) rather than storing glycogen, and the kidney/stomach are not major glycogen storage sites.

Question 44

The acid present in the stomach is?

Accepted Answer

Answer reason: Gastric parietal cells secrete hydrochloric acid (HCl) into the stomach lumen. HCl creates a very low pH that denatures proteins, helps activate pepsinogen to pepsin, and provides antimicrobial action. Sulphuric, nitric, and acetic acids are not the physiological acids secreted as the primary component of gastric juice.

Question 45

Dehydration in human body is caused due to the deficiency of ...?

Accepted Answer

Answer reason: Dehydration is defined as a deficit of total body water, most commonly from inadequate intake or excess losses (e.g., diarrhea, vomiting, sweating, diuresis). While electrolyte disturbances (like sodium changes) can accompany dehydration, the primary deficiency that causes dehydration is water itself. Vitamin deficiency and hormone deficiency are not the direct definition of dehydration, though some hormones (e.g., ADH) regulate water balance.

Question 46

The cell organ which is related to synthesis of ATP is-?

Accepted Answer

Answer reason: Mitochondria are the primary site of ATP production in eukaryotic cells via oxidative phosphorylation on the inner mitochondrial membrane. The electron transport chain generates a proton gradient that drives ATP synthase to form ATP from ADP and inorganic phosphate. Lysosomes are for intracellular digestion, the nucleus primarily stores genetic material and regulates transcription, and the Golgi apparatus modifies and packages proteins/lipids rather than producing ATP.

Question 47

The human ear helps in hearing and?

Accepted Answer

Answer reason: In addition to hearing, the ear contains the vestibular apparatus (semicircular canals and otolith organs) that detects head movement and position. These structures provide input needed to maintain equilibrium and coordinate posture and eye movements. Digestion, breathing, and vision are controlled by other organ systems, not the ear.

Question 48

Deficiency of which of the following causes non-clotting of blood?

Accepted Answer

Answer reason: Vitamin K is required for hepatic gamma-carboxylation and activation of clotting factors II, VII, IX, and X (and proteins C and S). Deficiency therefore impairs the coagulation cascade and can lead to prolonged PT/INR and bleeding described as “non-clotting” blood. Vitamin C deficiency primarily causes capillary fragility (scurvy), vitamin E excess/deficiency is not a primary cause of failure to clot, and vitamin B12 deficiency causes megaloblastic anemia and neurologic findings rather than a coagulation factor defect.

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Toxic substances are detoxified in human body in?

How much salt is present in our body?

Which organ is called the balancing organ?

Glucose stored in ...?

What is the normal body temperature of a healthy human?

Which of the following descriptions best defines general adaptation syndrome?

Which part of the body continues to grow throughout life?

The pH of human blood is?

A patient with liver failure is most likely to have low levels of?

A patient is admitted to the emergency department with hypoventilation and decreased respiratory rate after an opioid overdose. Arterial blood gas analysis reveals a pH of 7.29, PaCO2 of 60 mmHg, and HCO3- of 28 mEq/L. Which of the following compensatory mechanisms is expected in this patient?

Which of following called the powerhouse of cell?

Foremilk is rich in?

The process of fusion of male and female gametes in plants is called?

Which of the following is a sign of dehydration?

The main function of blood is to transport ____ and ____ to tissues?

In human body urea is synthesized by?

Hypothermia in preterm babies occurs due to?

Generally biological activity is relatively little?

Which type of muscle is involved in peristalsis?

Which of following has the highest protein content?

The first shunt to close after birth is?

Which plasma protein maintains colloid osmotic pressure?

Which organelle is responsible for protein modification, sorting, and packaging?

Lysosomes are produced by which of the following cell organelles?

Which enzyme digest plant proteins?

Normal pulse rate for a newborn is around?

Vibrating sound is transmitted by Tympanic membrane to one of the following structures?

What part of the brain controls breathing and heart rate?

Normal fetal heart rate is?

The element that helps in blood clotting?

Sunlight is the best source of which vitamin?

Which vessel carries the least oxygenated blood in fetus?

The normal range for adult respiratory rate is?

The spindle apparatus is formed during the -------- phase of mitosis?

Glucose stored in ...?

The organ that stores excess sugar than the body needs is?

In man, Cardiac Cycle duration is?

Which acid-base imbalance is most commonly associated with hyperventilation?

Which electrolyte is crucial for cardiac function?

Total volume of blood in a normal human being is?

Which of the following is the respiratory organ in earthworms?

The blood contains ?

Which organ stores glycogen in the human body?

The acid present in the stomach is?

Dehydration in human body is caused due to the deficiency of ...?

The cell organ which is related to synthesis of ATP is-?

The human ear helps in hearing and?

Deficiency of which of the following causes non-clotting of blood?

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The main function of blood is to transport and to tissues?