Biology - Comprehensive Mock Test 18

Question 171 Medium

ACTH stimulates the adrenal cortex to release a group of hormones called ______

A) Mineralocorticoid B) Glucocorticoid C) Endorphins D) Glucagon

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Question 172 Easy

Damage to thymus in children may lead to ?

A) Loss of antibody mediated immunity B) Reduction in stem cell production C) Reduction of hemoglobin content of blood D) Loss of cell-mediated immunity

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Question 173 Medium

Concentration of the urine is controlled by ______

A) MSH B) ADH C) Oxytocin D) ACTH

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Question 174 Medium

Cornea transplant in humans is almost never rejected. This is because?

A) It is a non-living layer B) Its cells are least penetrable by bacteria C) It has no blood supply D) It is composed of enucleated cells

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Question 175 Medium

The function of vagus nerve innervating the heart is to ?

A) Initiate the heart beat B) Reduce the heart beat C) Accelerate the heart beat D) Maintain constant heart beat

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Question 176 Medium

If vagus nerve in man is damaged, which of the following will not be affected?

A) pancreatic secretion B) gastrointestinal movements C) tongue movements D) cardiac movements

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Question 177 Medium

Unidirectional transmission of a nerve impulse through nerve fibre is due to the fact that?

A) nerve fibre is insulated by a medullary sheath B) sodium pump starts operating only at the cyton and then continues into the nerve fibre C) neurotransmitters are released by dendrites and not by axon endings D) neurotransmitters are released by the axon endings and not by dendrites

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Question 178 Medium

Patients suffering from cholera are given a saline drip because ?

A) NaCl is an important component of energy supply B) NaCl furnishes most of the fuel required for cellular activity C) Na+ ions help in stopping nerve impulses and hence, sensation of pain D) Na+ ions help in the retention of water in the body tissues

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Question 179 Hard

During the transmission of nerve impulse through a nerve fibre, the potential on the inner side of the plasma membrane has which type of electric charge?

A) First positive, then negative and continue to be negative B) First negative, then positive and again back to negative C) First positive, then negative and again back to positive D) First negative, then positive and continue to be positive.

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Question 180 Medium

Which one of the following is an example of negative feedback loop in humans?

A) Constriction of skin blood vessels and contraction of skeletal muscles when it is too cold B) Secretion of tears after falling of sand particles into the eyes C) Salivation of mouth at the sight of delicious food D) Secretion of sweat glands and constriction of skin blood vessels when it is too hot

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