Question 1

During slow wave sleep (stage 3 and 4 NREM sleep)?

Accepted Answer

Answer reason: In slow-wave (stage 3–4) NREM sleep, arousal disorders such as sleepwalking (somnambulism) and night terrors typically occur; REM is the stage most associated with dreaming. Cortisol is not highest in slow-wave sleep, and growth hormone peaks—so stating it is lowest is incorrect.

Question 2

Which of the following is correct?

Accepted Answer

Answer reason: By osmosis, water moves across a semipermeable membrane from a region of lower solute concentration (less concentrated) to higher solute concentration (more concentrated).

Question 3

A pregnant patient presents with a dark vertical line running from the umbilicus to the pubic region. What is this line called?

Accepted Answer

Answer reason: Linea nigra develops due to increased melanocyte-stimulating hormone and estrogen during pregnancy, causing hyperpigmentation along the midline of the abdomen. It is a normal physiologic change.

Question 4

A pregnant woman has a dark vertical abdominal line from umbilicus to pubis. What is this called?

Accepted Answer

Answer reason: Hormonal changes in pregnancy increase melanocyte activity, causing midline hyperpigmentation known as linea nigra.

Question 5

Which hormone increases during pregnancy and causes hyperpigmentation such as linea nigra and melasma?

Accepted Answer

Answer reason: MSH increases during pregnancy and stimulates melanocytes to produce more melanin, leading to pigment changes such as linea nigra and melasma.

Question 6

The normal pH of human blood is–?

Accepted Answer

Answer reason: Normal arterial blood pH is tightly regulated around 7.35–7.45, with 7.4 as the commonly cited midpoint. This balance is maintained by the bicarbonate buffer system, respiratory CO2 regulation, and renal acid-base handling. Values below 7.35 indicate acidemia and above 7.45 indicate alkalemia, both of which can impair cellular function.

Question 7

Which organ is called the "control center" of the body?

Accepted Answer

Answer reason: The brain serves as the body’s control center by integrating sensory input and coordinating motor output. It regulates conscious activities such as movement and cognition and oversees involuntary functions through the autonomic nervous system. Structures like the hypothalamus help maintain homeostasis, controlling temperature, hunger, and endocrine responses.

Question 8

Mitochondria function in the synthesis of?

Accepted Answer

Answer reason: Mitochondria are the primary site of oxidative phosphorylation, where the electron transport chain generates a proton gradient used by ATP synthase to produce ATP from ADP and inorganic phosphate. While mitochondria contain their own DNA and can transcribe RNA, their hallmark function is cellular energy production. Therefore, the product most associated with mitochondrial function is ATP.

Question 9

The "blood bank" of our body is?

Accepted Answer

Answer reason: The spleen functions as a major blood reservoir, storing several hundred milliliters of blood that can be mobilized during hemorrhage or sympathetic stimulation. It also removes aged erythrocytes and participates in immune surveillance. While the liver can hold some blood, the classic and primary physiologic 'blood bank' is the spleen. The lungs and heart do not serve as blood reservoirs in this sense.

Question 10

Which of the following is correctly matched?

Accepted Answer

Answer reason: Olfactory receptors in the nasal mucosa are chemoreceptors that detect odorant chemicals, making this the correct match. Photoreceptors are in the retina of the eye, not the ear. Auditory receptors (mechanoreceptors/phonoreceptors) are in the ear, not the eye. Gustatory receptors for taste are located on the tongue and palate, not the skin.

Question 11

During dehydration, the substance that the body usually loses is?

Accepted Answer

Answer reason: Dehydration typically involves loss of water along with extracellular electrolytes, especially sodium and chloride, through sweat, vomiting, or diarrhea. Sodium is the primary extracellular cation and chloride the major anion, making NaCl the predominant salt lost in body fluids. Potassium losses are smaller by comparison, and sugar or calcium phosphate are not typically lost in significant amounts during dehydration.

Question 12

The example of ECF is-?

Accepted Answer

Answer reason: Extracellular fluid (ECF) encompasses all body fluids outside cells, including interstitial fluid, plasma, and transcellular fluids. CSF is a transcellular ECF, interstitial fluid bathes the tissues, and the plasma component of blood is part of ECF. Therefore, each listed option represents an ECF compartment, making 'All of these' correct.

Question 13

Human blood bank is?

Accepted Answer

Answer reason: The spleen serves as a reservoir for blood and platelets, releasing them during hemorrhage or stress, which is why it is called the body's blood bank. It also filters circulating blood, removes senescent red blood cells, and recycles iron. While the liver and heart are highly vascular, they do not function as primary blood reservoirs.

Question 14

Body temperature is regulated by ...?

Accepted Answer

Answer reason: Thermoregulation is controlled by the preoptic area of the anterior hypothalamus, which acts as the body’s thermostat. It integrates input from central and peripheral thermoreceptors and initiates responses such as sweating, vasodilation, shivering, and behavioral changes to maintain set-point temperature. The medulla coordinates autonomic functions like respiration and circulation, the pituitary mediates endocrine responses, and the cerebrum handles higher cognition.

Question 15

Human blood bank is called-?

Accepted Answer

Answer reason: The spleen acts as a reservoir for blood, storing red blood cells and about one-third to two-fifths of the body’s platelets. During hemorrhage or stress, it can contract to release these cells into circulation, functioning like a physiologic ‘blood bank.’ It also filters aged or damaged erythrocytes and participates in immune responses.

Question 16

The PH of human blood is between?

Accepted Answer

Answer reason: Normal arterial blood pH is tightly regulated between 7.35 and 7.45, reflecting a slightly alkaline state. This range is maintained by the bicarbonate buffer system along with respiratory and renal compensation. Values like 6.5–7 or 4.5–5 are too acidic and incompatible with normal physiology, while 8–9 is excessively alkaline. Therefore, 7.35–7.45 is the correct range.

Question 17

Increase in the size or mass of the tissue is?

Accepted Answer

Answer reason: Growth refers to an increase in size or mass of tissues or the organism, typically through hypertrophy and/or hyperplasia. Maturation is the process of reaching functional or full developmental capacity. Development describes qualitative changes such as differentiation and complexity. Progress of skill relates to acquisition of abilities and does not indicate tissue mass increase.

Question 18

PH of blood?

Accepted Answer

Answer reason: Normal arterial blood pH is tightly regulated around 7.35–7.45, with 7.4 as the typical midpoint. This alkalinity is maintained by the bicarbonate buffer system and respiratory and renal compensation. Values such as 5, 6.8, or 7 are far too acidic and would be incompatible with normal physiologic function. Therefore, 7.4 is the best answer.

Question 19

Low calcium level in the body fluid may be the cause of?

Accepted Answer

Answer reason: Hypocalcemia increases neuromuscular excitability by lowering the threshold potential, leading to paresthesias, muscle cramps, and carpopedal spasm—classic findings of tetany. Angina pectoris is due to myocardial ischemia, not low calcium. Anaemia reflects reduced red-cell mass or hemoglobin. Gout results from hyperuricemia with urate crystal deposition, unrelated to hypocalcemia.

Question 20

The normal pH of human blood is?

Accepted Answer

Answer reason: Normal arterial blood pH is tightly regulated around 7.35–7.45, commonly cited as 7.4. This range is maintained by the bicarbonate buffer system along with respiratory and renal compensation. A pH of 6.4 is incompatible with life and 7.0 is neutral water, not physiologic for blood. A pH of 7.5 indicates alkalemia.

Question 21

In laminar flow, streamlines?

Accepted Answer

Answer reason: In laminar flow, fluid particles move in smooth, orderly layers and each point in the fluid has a single velocity vector at a given time. Streamlines are tangent to the local velocity field, so they cannot cross—intersection would imply two different velocities at the same point. Random or crossing paths characterize turbulent flow, not laminar. A parabolic description applies to the velocity profile in a pipe, not to the streamlines themselves.

Question 22

Cardiac muscles are–?

Accepted Answer

Answer reason: Cardiac muscle contains sarcomeres, giving it a striated appearance similar to skeletal muscle. However, it contracts without conscious control and is regulated by the autonomic nervous system and intrinsic pacemaker cells, making it involuntary. Intercalated discs with gap junctions coordinate synchronized, rhythmic contractions of the heart.

Question 23

The powerhouse of the cell is–?

Accepted Answer

Answer reason: Mitochondria generate most of the cell’s ATP via oxidative phosphorylation, making them the primary energy source or “powerhouse.” The nucleus stores genetic material and regulates gene expression, not energy production. Ribosomes synthesize proteins. Chloroplasts carry out photosynthesis in plants and are not the main ATP source in animal cells.

Question 24

Blood is?

Accepted Answer

Answer reason: Normal arterial blood pH is about 7.35–7.45, making it slightly alkaline rather than neutral or acidic. While blood contains buffer systems (bicarbonate, phosphate, proteins) to resist pH changes, its inherent pH is alkaline. Therefore, the best single descriptor is alkaline.

Question 25

Which of the following organs of human body provides instant energy?

Accepted Answer

Answer reason: The liver stores glycogen and can rapidly convert it to glucose (glycogenolysis), releasing it into the bloodstream to provide immediate energy during acute demand. Lungs provide oxygen for metabolism but do not supply energy substrates. The pancreas regulates glucose via hormones but does not directly provide energy. Muscles use their own ATP and glycogen locally rather than supplying the body with instant energy.

Question 26

Daily insensible water loss?

Accepted Answer

Answer reason: Insensible water loss occurs via evaporation from the skin and water vapor from the lungs and is not measurable. In a temperate environment for a healthy adult, this typically totals about 400–800 mL/day. It increases with fever, hyperventilation, or high ambient temperature but is lower than renal or gastrointestinal losses. Therefore, 400–800 mL is the best estimate.

Question 27

Freely permiable through mictochondrial membrane___________?

Accepted Answer

Answer reason: The inner mitochondrial membrane is highly selective and largely impermeable to ions and most polar solutes, but small nonpolar molecules and water can cross. Water moves readily via aquaporins (e.g., AQP8) and simple diffusion. In contrast, charged species typically require specific carriers or channels. Therefore, H2O is considered freely permeable compared with the other listed options.

Question 28

Maximum amount of urea present in...?

Accepted Answer

Answer reason: Urea is synthesized in the liver from ammonia via the urea cycle. Blood leaving the liver through the hepatic vein therefore has the highest urea concentration. The renal vein has reduced urea because the kidneys filter and excrete it. The hepatic portal vein carries nutrient-rich blood from the gut before hepatic conversion, and the dorsal aorta reflects systemic arterial levels, both lower than hepatic venous blood.

Question 29

Normal body temperature in Celsius is?

Accepted Answer

Answer reason: Normal adult core body temperature is about 37°C, with a typical resting range around 36–37°C depending on site and circadian variation. A temperature of 34°C indicates hypothermia. Temperatures of 39°C and 41°C reflect fever and hyperpyrexia, respectively, not normal. Therefore, 36–37°C is the correct normal range.

Question 30

Newborn jaundice appears due to?

Accepted Answer

Answer reason: Neonatal jaundice is caused by hyperbilirubinemia—an accumulation of unconjugated bilirubin from increased red cell turnover and immature hepatic conjugation. The yellow discoloration of skin and sclera typically appears when total serum bilirubin exceeds about 5 mg/dL. Low glucose, infection, or dehydration do not directly cause jaundice, though they may exacerbate illness severity. Therefore, elevated bilirubin is the primary cause.

Question 31

Power house of the cell is called?

Accepted Answer

Answer reason: Mitochondria are termed the powerhouse of the cell because they produce most of the cell’s ATP via oxidative phosphorylation along the inner mitochondrial membrane. They have a double membrane with cristae that increase surface area for ATP-generating reactions. The nucleus stores genetic material, ribosomes synthesize proteins, and chloroplasts perform photosynthesis in plant cells, not ATP production for animal cells.

Question 32

Fever is generally defined as body temperature above?

Accepted Answer

Answer reason: Normal core temperature varies around 36.5–37.5°C. Most clinical guidelines define fever as a temperature of at least 38.0°C (100.4°F) when measured orally or rectally. Values like 37–37.5°C can be normal variation or low-grade elevation and do not meet the standard fever threshold, whereas 39°C indicates a high fever.

Question 33

Excess vomiting causes—?

Accepted Answer

Answer reason: Prolonged vomiting leads to loss of gastric hydrochloric acid, resulting in a net loss of hydrogen ions and chloride. This produces a metabolic alkalosis, often accompanied by volume contraction and hypochloremia. Acidosis is seen more with diarrhea or renal acid retention, not vomiting. Hypoxia and hyperglycemia are not primary consequences of emesis.

Question 34

Which organ can regenerate itself—even if 75% is removed?

Accepted Answer

Answer reason: The liver has remarkable regenerative capacity and can restore its mass after a major partial hepatectomy, even when 70–75% is removed. Hepatocytes re-enter the cell cycle under the influence of cytokines (e.g., IL-6) and growth factors such as HGF. In contrast, the heart and brain have minimal true regenerative ability, and while lungs can repair tissue, they do not reliably regenerate to this extent.

Question 35

The normal range of body temperature in Celsius is?

Accepted Answer

Answer reason: Normal core body temperature is regulated around 37°C with typical daily variation of about ±0.5°C. Thus, values between roughly 36.5–37.5°C are considered normal. Among the options, 36–37°C best represents the normal range, whereas 37–38°C trends into low-grade fever and 35–36°C suggests hypothermia.

Question 36

In the human body, fats are stored in the ...?

Accepted Answer

Answer reason: Adipose tissue contains adipocytes specialized for storing triglycerides and serves as the body’s primary long-term energy reservoir. The epidermis and epithelium are protective tissue layers and are not major fat stores. The liver metabolizes and packages fats but is not the main storage site; excess energy is stored predominantly in adipose tissue.

Question 37

The study of function of the body is called?

Accepted Answer

Answer reason: Physiology is the science of how the body and its parts function. Anatomy describes structures, morphology focuses on form and structure more broadly, and cytology studies cells. Therefore the term that specifically denotes the study of bodily functions is physiology.

Question 38

Which of organic continuously works (24 hours)?

Accepted Answer

Answer reason: The heart contracts continuously to maintain circulation and perfusion, driven by intrinsic pacemaker activity that functions without rest, even during sleep. Eyes rest and close during sleep, and visual processing diminishes. Nasal airflow is not continuous because mouth breathing can occur. While the brain remains active during sleep, the classic physiologic organ that mechanically works nonstop to sustain life is the heart.

Question 39

Hindmilk is richer in?

Accepted Answer

Answer reason: Hindmilk is the milk delivered later in a feeding as the breast empties. Its fat content rises substantially, providing higher energy density that promotes satiety and weight gain. Protein and lactose concentrations remain relatively constant throughout a feed, and foremilk is more watery. Therefore, hindmilk is richer in fat.

Question 40

What is the normal pH of human blood?

Accepted Answer

Answer reason: Normal arterial blood pH is tightly regulated around 7.35–7.45, making 7.4 the best answer. This range is maintained by the bicarbonate buffer system, respiratory control of CO2, and renal regulation of bicarbonate and hydrogen ions. A pH of 7.0 is neutral and indicates significant acidemia, 6.5 is incompatible with life, and 8.0 reflects severe alkalemia outside physiologic norms.

Question 41

The predominant cation in the intracellular compartment is?

Accepted Answer

Answer reason: Potassium is the major intracellular cation, maintaining the cell’s resting membrane potential and osmotic balance. Sodium is the predominant extracellular cation, while chloride is an anion. Magnesium is an important intracellular cation but is less abundant than potassium. Free cytosolic calcium is kept very low, with most calcium stored in organelles or extracellularly.

Question 42

Dehydration means loss of?

Accepted Answer

Answer reason: Dehydration is defined as a deficit of total body water when fluid output exceeds intake. It primarily refers to loss of water from the body’s compartments, leading to hypovolemia and increased serum osmolality. Blood loss is hemorrhage, plasma loss is a component of volume depletion but not the definition, and glucose loss does not define dehydration.

Question 43

The "Blood bank" of our body is ______?

Accepted Answer

Answer reason: The spleen functions as a reservoir for blood, storing red blood cells and platelets that can be released during hemorrhage or increased demand (e.g., exercise). It also filters aged or damaged erythrocytes and participates in immune responses. While the liver can hold some blood, the primary physiologic "blood bank" is the spleen.

Question 44

Energy is used to move molecules by?

Accepted Answer

Answer reason: Active transport requires cellular energy, typically ATP, to move molecules across membranes against their concentration or electrochemical gradients. In contrast, diffusion and osmosis are passive processes driven by gradients and do not require energy. Passive transport encompasses diffusion, osmosis, and facilitated diffusion, all energy-independent.

Question 45

........... Is refers to as the power house of the cell?

Accepted Answer

Answer reason: Mitochondria generate most of the cell’s ATP through oxidative phosphorylation, so they are known as the cell’s powerhouse. Ribosomes are responsible for protein synthesis, not energy production. The nucleus stores genetic material and controls gene expression but does not produce ATP. Therefore, mitochondria best fit the description.

Question 46

Angiotensin converting enzyme is secreted from?

Accepted Answer

Answer reason: Angiotensin-converting enzyme (ACE) is produced predominantly by the endothelial cells of the pulmonary capillaries. It converts angiotensin I to angiotensin II and also degrades bradykinin. Although ACE is present in other tissues (e.g., kidneys and endothelium elsewhere), the lungs are the principal source for systemic ACE activity.

Question 47

Which of organ continuously works (24 hours)?

Accepted Answer

Answer reason: The heart contracts continuously from birth to death, driven by the sinoatrial node and cardiac conduction system, with only brief diastolic intervals between beats, not periods of rest. Eyes rest during sleep and vision is inactive when closed. The brain remains metabolically active but its activity cycles with sleep; it is not a continuously contracting organ. The nose is a conduit for airflow, not an organ with constant active work like the heart.

Question 48

What is the normal human body temperature?

Accepted Answer

Answer reason: Normal adult oral body temperature is approximately 37°C, which equals 98.6°F. Typical physiologic variation ranges around 36.4–37.6°C depending on site and circadian rhythm. Options 81.1°F and 95.9°F indicate hypothermia, while 37.5 labeled in °F is a unit error (37.5°C ≈ 99.5°F). Therefore, 98.6°F is the best answer.

Question 49

What is the Ph value of human blood?

Accepted Answer

Answer reason: Normal arterial blood pH is tightly regulated around 7.35–7.45, with 7.40 as the typical midpoint. This narrow range is essential for enzyme function and oxygen delivery. A pH of 7.00 is neutral and reflects severe acidemia, 8.00 is incompatible with life, and 0.00 is impossible physiologically.

Question 50

What is the first sign of clinical death?

Accepted Answer

Answer reason: Clinical death is defined by the cessation of circulation and respiration, with loss of an effective heartbeat being primary. Absence of a pulse indicates no perfusion and thus clinical death, even if agonal respirations may still be observed transiently. Lack of breathing alone can occur in respiratory arrest without immediate clinical death, and dilated pupils are a later, hypoxia-related sign.

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