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29 questions with worked solutions.
Q1. Hemoglobin in the RBCs helps in the
Answer: Both A and C
Hemoglobin’s primary role is to carry oxygen from the lungs to tissues. It also helps transport carbon dioxide back to the lungs, so the best choice includes both gases.
Answer: (1)-water, (2)-electrolytes, (5)-renin
The ascending limb of Henle’s loop is impermeable to water but actively transports electrolytes, so (1) = water and (2) = electrolytes. Also, a fall in renal perfusion/GFR stimulates juxtaglomerular cells to release renin, not angiotensin or angiotensinogen.
Q3. Secretin stimulates secretion of bicarbonate from
Answer: Pancreas
Secretin is released from the duodenum in response to acid and stimulates pancreatic duct cells to secrete bicarbonate-rich fluid. This bicarbonate helps neutralize gastric acid in the small intestine.
Q4. The upper chambers of the heart are called
Answer: Auricles
The upper chambers of the heart are the atria, also called auricles in some contexts. Ventricles are the lower pumping chambers, while the other options are unrelated terms.
Q5. Dialysis fluid contains all the constituents as in plasma except
Answer: Proteins
Dialysis fluid is formulated to resemble plasma in small dissolved substances so exchange can occur without major shifts. Proteins are excluded because they are large molecules and are not normally present in dialysis fluid.
Q6. Red blood cells
Answer: Do not divide
Mature red blood cells are anucleate and lack the machinery needed for cell division. They are produced in the bone marrow from precursors, but once mature they do not divide.
Q7. Heart beat is accelerated by
Answer: Sympathetic nerves and noradrenaline
Heart rate increases when sympathetic stimulation acts on the heart, mainly through noradrenaline released from sympathetic nerve endings. This speeds the SA node and strengthens cardiac activity.
Q8. In humans, the concentration of carbon dioxide in the plasma
Answer: Regulates breathing rate by its effect on the medulla
Carbon dioxide in plasma is a major driver of respiration because it alters blood pH and is detected by chemoreceptors that influence the medulla. The medulla then adjusts breathing rate and depth to restore CO2 and pH balance.
Q9. Incorrect statement in the following
Answer: Symptoms of uremia is swelling of feet
The incorrect statement is the one about uremia because swelling of feet is not a defining symptom of uremia. The other options are correct facts about kidney anatomy or bio-diesel sources.
Answer: 15 litres/min
Normal resting cardiac output is about 5 litres per minute in a healthy adult. Since 15 litres/min is not the standard normal value, the given correct answer does not match typical physiology.
Q11. Which organ is part of circulatory system but does not take part in pumping?
Answer: spleen
The spleen is associated with the circulatory system because it filters blood and helps remove old blood cells. Unlike the heart, it does not pump blood.
Q12. Sensory crista of ampulla of mammalian ear is connected with
Answer: Sense of balance
The sensory crista in the ampulla is part of the vestibular apparatus of the inner ear. It detects angular movements of the head, so it is involved in maintaining balance, not hearing.
Q13. The breakdown of complex components of food into simple ones is called as
Answer: Digestion
Digestion is the process in which complex food molecules are broken down into simpler substances. This makes nutrients small enough to be absorbed and used by the body.
Q14. Enzyme renin is secreted by
Answer: The cells of juxtaglomerular apparatus of kidney
Renin is produced by juxtaglomerular (granular) cells in the juxtaglomerular apparatus of the kidney. These cells release renin in response to low renal perfusion, low sodium delivery, or sympathetic stimulation.
Q15. In humans, blood vascular system has
Answer: Double circulation
Humans have two separate circuits: pulmonary circulation and systemic circulation. Because blood passes through the heart twice in one complete round, the system is called double circulation.
Q16. How many nodes are found in heart of human?
Answer: Two
The human heart has two main nodes in its conduction system: the sinoatrial (SA) node and the atrioventricular (AV) node. These coordinate the heartbeat by starting and passing on electrical signals.
Answer: Oxygenated blood to brain
The carotid arteries are the main arteries in the neck that carry oxygen-rich blood to the head and brain. They do not supply the lungs or intestine, so the correct choice is oxygenated blood to the brain.
Q18. The opening of the urinary bladder is
Answer: Urethra
The urinary bladder stores urine and releases it through the urethra. Ureters bring urine from the kidneys to the bladder, while the urethra is the outlet from the bladder to the exterior.
Q19. Which of the following statements is false?
Answer: The term pleura refers to the double layered covering of the kidney.
Pleura is the double-layered membrane surrounding the lungs, not the kidney. The other statements are correct: the pulmonary artery carries blood from the right heart to the lungs, the pancreas has both exocrine and endocrine functions, and scurvy results from vitamin C deficiency.
Q20. The average lung capacity is
Answer: 7 litres
The average total lung capacity in an adult is commonly given as about 7 litres in basic physiology references. This is the standard rounded value among the options provided.