Biology · General Awareness

Human Endocrine System

1,530 Questions

The human endocrine system comprises glands that secrete hormones to regulate bodily functions like metabolism, growth, and reproduction. Competitive exams frequently test the specific roles of hormones such as adrenaline, insulin, and progesterone. Use these questions to master the locations and functions of different hormones.

Hormone functionsIslets of LangerhansFight or flight responseBlood pressure regulationFemale sex hormonesWater soluble hormones

Human Endocrine System Questions

Multiple choice

What is the primary function of Leydig cells of the testes?

  1. Regulating pituitary secretion of prolactin

  2. Inhibin secretion

  3. Nitric oxide release

  4. Testosterone synthesis

  5. Synthesis of androgen binding protein
Reveal answer Fill a bubble to check yourself
D Correct answer
Explanation

The primary function of Leydig cells is to synthesize and secrete testosterone. Leydig cells do this in a dose-dependent manner in response to LH.

Multiple choice

Which hormones initiate the growth of pubic and axillary hair?

  1. hCG

  2. FSH

  3. ACTH

  4. IGF-1

  5. DHEA and DHEA-S
Reveal answer Fill a bubble to check yourself
E Correct answer
Explanation

In males and females, the adrenal gland produces and secretes increased amounts of several weak androgens during puberty: androstenedione, dehydroepiandrosterone (DHEA) and dehydroepiandrosterone sulfate (DHEA-S). DHEA and DHEA-S are responsible for the commencement of pubic and axillary hair growth.

Multiple choice

Arrange the following in correct sequence of signal transduction pathway:

  1. Hormone
  2. 7 TM receptor
  3. G protein
  4. cAMP
  5. PKA

  1. 1 → 2 → 3 → 4 → 5

  2. 1 → 3 → 2 → 4 → 5

  3. 1 → 4 → 3 → 2 → 5

  4. 5 → 2 → 3 → 4 → 1

  5. 5 → 4 → 3 → 2 → 1
Reveal answer Fill a bubble to check yourself
A Correct answer
Explanation

Correct answer. Correct sequence of signal transduction pathway is Hormone → 7 TM receptor → G protein → cAMP → PKA. In the G protein associated signal cascade system, binding of hormone to a cell surface receptor, like the 7TM (a 7 transmembrane alpha helices) which is a part of G protein. This will activate production of second messengers like cAMP by the enzyme adenylate cyclase. The cAMP in turn binds and activates downstream signal proteins line cAMP dependent protein kinase A (PKA).