All Free Biology MCQs with Answers

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19844 questions · page 708 of 1985

7071. Which one of the following is only a glucocorticoid?

Moderate
  • A. Cortisol
  • B. Aldosterone
  • C. Corticosterone
  • D. Androgen

Explanation: Cortisol is a pure glucocorticoid, regulating metabolism, blood glucose, and stress responses. Aldosterone is a mineralocorticoid.

Correct answer: Cortisol

7072. Which one of the following is exclusively a mineralocorticoid?

Moderate
  • A. Cortisol
  • B. Aldosterone
  • C. Corticosterone
  • D. Androgen

Explanation: Aldosterone is the chief mineralocorticoid, maintaining Na+/K+ balance and blood pressure. Cortisol, in contrast, is a glucocorticoid.

Correct answer: Aldosterone

7073. All of the following are produced in adrenal gland, except:

Moderate
  • A. Epinephrine
  • B. Cortisol
  • C. Calcitriol
  • D. Androgen

Explanation: Calcitriol (active vitamin D3) is produced in the kidney, not adrenal gland. Adrenal gland produces epinephrine, cortisol, and androgens.

Correct answer: Calcitriol

7074. Aggressive behavior during routine life can be a symptom of:

Moderate
  • A. Hyperthyroidism
  • B. Overproduction of STH
  • C. Overproduction of adrenal cortex
  • D. Overproduction of adrenal medulla

Explanation: The excess secretion of epinephrine/norepinephrine from adrenal medulla increases aggression, anxiety, BP, and heart rate.

Correct answer: Overproduction of adrenal medulla

7075. Peripheral vasoconstriction is a function of:

Moderate
  • A. Vasopressin
  • B. Secretin
  • C. Epinephrine
  • D. Norepinephrine

Explanation: Norepinephrine causes vasoconstriction by acting on α- adrenergic receptors, helping raise blood pressure during stress.

Correct answer: Norepinephrine

7076. Which one is not due to adrenal cortical abnormality?

Moderate
  • A. Addison's disease
  • B. Cushing's disease
  • C. Failure to cope stress
  • D. Tay Sachs disease

Explanation: Tay-Sachs is a genetic lipid storage disorder, unrelated to adrenal cortex. Addison's and Cushing's are adrenal cortical disorders

Correct answer: Tay Sachs disease

7077. A tumor in the inner part of adrenal cortex in female results in all except:

Moderate
  • A. Sterility
  • B. Male-like characters in female
  • C. Over androgen production
  • D. High steroid level in blood

Explanation: Tumors of adrenal cortex increase androgens, leading to virilization and high steroids. Sterility is not a direct result.

Correct answer: Sterility

7078. The action of epinephrine and nor-epinephrine differs on vessels supplying blood to:

Moderate
  • A. All parts of body
  • B. Skin and gut
  • C. Brain and muscles
  • D. Skin and muscles

Explanation: In stress response, epinephrine and norepinephrine constrict skin/gut vessels to divert blood toward muscles and brain.

Correct answer: Skin and gut

7079. Diabetes insipidus is associated with:

Moderate
  • A. Insulin
  • B. Glucagon
  • C. Glucocorticoid
  • D. Vasopressin

Explanation: Diabetes insipidus is due to deficiency or insensitivity of ADH (vasopressin), leading to excessive urination and thirst.

Correct answer: Vasopressin

7080. Which one of the following is not a tropic hormone?

Moderate
  • A. TSH
  • B. FSH
  • C. ACTH
  • D. ADH

Explanation: Tropic hormones stimulate other endocrine glands. ADH (vasopressin) acts directly on kidneys, so it is not tropic.

Correct answer: ADH