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 zoology the endocrine system adrenal gland thymus and adrenal gland adrenal glands

The fight-or-flight response is developed by the hormones of

  1. hypothalamus

  2. middle pituitary

  3. adrenal medulla

  4. adrenal cortex
Reveal answer Fill a bubble to check yourself
C Correct answer
Explanation

The adrenal medulla secretes two hormones called adrenaline or epinephrine and noradrenaline or norepinephrine. These are commonly called as catecholamines. Adrenaline and noradrenaline are rapidly secreted in response to the stress of any kind and during emergency situations and are called emergency hormones or hormones of Fight or Flight.

So the correct option is adrenal medulla.

Multiple choice zoology the endocrine system adrenal gland thymus and adrenal gland adrenal glands

Which of the following is a mineralocorticoid?

  1. Testosterone

  2. Progesterone

  3. Adrenaline

  4. Aldosterone
Reveal answer Fill a bubble to check yourself
D Correct answer
Explanation

Aldosterone is a major mineralocorticoid, secreted by adrenal cortex. It regulates mineral metabolism and controls the sodium and potassium ratio in the extracellular and intracellular fluid. Therefore, it is called salt-retaining hormone.

Multiple choice zoology the endocrine system adrenal gland thymus and adrenal gland adrenal glands

Reabsorption of $Na^+$ is controlled by which one of the following hormones?

  1. Aldosterone

  2. Estrogen

  3. Glucocorticoids

  4. Testosterone
Reveal answer Fill a bubble to check yourself
A Correct answer
Explanation

Aldosterone(secreted by adrenal medulla) acts mainly on the renal tubules and stimulates the reabsorption of $Na^+$ and water and excretion of $K^+$ and phosphate ions.

Multiple choice zoology the endocrine system adrenal gland thymus and adrenal gland adrenal glands

Glucocorticoid hormones are secreted by the:

  1. adrenal medulla

  2. islets of Langerhans

  3. parafollicular cells

  4. adrenal cortex
Reveal answer Fill a bubble to check yourself
D Correct answer
Explanation

(a) The adrenal medulla secretes two hormones called adrenaline and noradrenaline.

(b) The pancreas is a composite glans which acts as both exocrine and endocrine gland. The endocrine pancreas consists of Islets of Langerhans. 
(c) Parafollicular cells are neuroendocrine cells in the thyroid which primary function is to secrete calcitonin.
(d) The adrenal cortex secretes many hormones called as corticoids. The corticoids which are involved in carbohydrate metabolism are called glucocorticoids. 
So the correct option is adrenal cortex.

Multiple choice zoology the endocrine system adrenal gland thymus and adrenal gland adrenal glands

Which of the following hormones is not proteinaceous is nature?

  1. TSH

  2. Aldosterone

  3. LH

  4. FSH
Reveal answer Fill a bubble to check yourself
B Correct answer
Explanation

Aldosterone is a steroid hormone and has three cyclohexyl rings and one cyclopentyl ring joined into a single structure. TSH, FSH and LH are peptide hormones and have long amino acid chains. Thus, the correct answer is option B. 

Multiple choice zoology the endocrine system adrenal gland thymus and adrenal gland adrenal glands

Zona fasciculata secretes

  1. Aldosterone

  2. Cortisol

  3. Thyroxine

  4. Adrenaline
Reveal answer Fill a bubble to check yourself
B Correct answer
Explanation

Adrenal gland just lies above the kidney. It is divided into two regions outer cortex and inner medulla. Cortex region secret the steroid hormone. Inner medulla region is divided into three regions zona glomerulosa, zona fasiculata and zona reticularis. Each zone is responsible for secreting specific hormone.

 Name of the hormone Organ 
 Aldosterone  Secreted by zona glomerulosa (adrenal cortex)
 Cortisol Secreted by zona fasiculata (adrenal cortex)
 Thyroxine  Secreted by the thyroid gland
 Adrenaline  Secreted by the adrenal medulla

So, the correct answer is ' Cortisol '

Multiple choice zoology the endocrine system adrenal gland thymus and adrenal gland adrenal glands

Which of the following induces goose flesh?

  1. Adrenal Cortex

  2. Adrenal medulla

  3. Pituitary

  4. Thyroxine
Reveal answer Fill a bubble to check yourself
B Correct answer
Explanation

Goose flesh (piloerection) is caused by the contraction of arrector pili muscles, which is mediated by the sympathetic nervous system and the release of epinephrine (adrenaline) from the adrenal medulla.

Multiple choice zoology the endocrine system adrenal gland thymus and adrenal gland adrenal glands

Which one of the following hormones also produces anti-inflammatory reactions in man and suppresses the immune response in addition to its primary functions?

  1. Thyrocalcitonin

  2. Cortisol

  3. Erythropoietin

  4. Thymosin
Reveal answer Fill a bubble to check yourself
B Correct answer
Explanation

Cortisol has a powerful anti-inflammatory action, even when secreted at normal levels. It acts quickly to remove and prevent redness and swelling of nearly all tissues. Cortisol also reduces the rate at which lymphocytes multiply and accelerates their programmed cell death to further protect the body from this overreaction. In fact, when cortisol is elevated during the alarm reaction stage, there is almost a complete disappearance of lymphocytes from the blood. That is why the immune system is suppressed when the body is under stress or taking corticosteroids. 

So, the correct answer is B.

Multiple choice zoology the endocrine system adrenal gland thymus and adrenal gland adrenal glands

The main mineralocorticoid in human is

  1. aldosterone

  2. cortisol

  3. testosterone

  4. adrenaline
Reveal answer Fill a bubble to check yourself
A Correct answer
Explanation

Mineralocorticoids: These hormones are secreted by the outer region of the adrenal cortex. They regulate mineral metabolism.

A. Aldosterone: The major mineralocorticoid is aldosterone, commonly called salt-retaining hormone. It tends to increase the reabsorption of sodium from urine, saliva, bile and sweat to reduce its loss from the body.
B. Cortisol: It is a glucocorticoid.
C. Testosterone: It is a sexcorticoids.
So, the correct answer is 'Aldosterone'.

Multiple choice zoology the endocrine system adrenal gland thymus and adrenal gland adrenal glands

Which of the following option is correct for the secretion of the adrenal cortex?
(i)   Mineralocorticoids are secreted by Zona Fasciulata.
(ii)  Zona Glomerulosa regulates the balance of water and Na$^{+2}$.
(iii) Sex corticoids are secreted by both Zona Fasciculata and Zona Reticularis.
(iv) Zona Glomerulosa regulates carbohydrate, protein and fat metabolism.

  1. (ii), (iii)

  2. (i), (iv)

  3. (ii), (iv)

  4. (i), (iii), (iv)
Reveal answer Fill a bubble to check yourself
A Correct answer
Explanation

Glucocorticoids are secreted by Zona fasciculata. Mineralocorticoids are secreted by the Zona glomerulosa of the adrenal cortex.Zona glomerulosa is the outermost layer of the adrenal cortex. The hormone regulates electrolyte balance. It regulates the balance of water and Na$^{+2}$ ions. Zona reticularis secretes androgens like dehydroepiandrosterone (DHEA) and androstenedione. 

Thus, the correct answer is '(ii), (iii).'

Multiple choice zoology endocrine system and chemical co-ordination adrenal gland thymus and adrenal gland adrenal glands

RAAS secrete which of the following hormone

  1. Mineralocorticoids

  2. Glucocorticoids

  3. Both 1 and 2

  4. None of these
Reveal answer Fill a bubble to check yourself
A Correct answer
Explanation

RAAS stands for rennin- angiotensin- aldosterone system. It is a hormone system that regulates blood pressure and fluid balance in the body. When blood pressure is low, the juxtaglomerular cells in the kidney release renin, which convert the angiotensinogen into angiotensin I after that it changes into angiotensin Ii. Angiotensin II (mineralocorticoids)is a vasoconstrictor that increases the blood pressure. Aldosterone is released by the adrenal gland. It is a mineral corticoid. It increases the absorption from distal convoluted tubule and collecting duct of kidney's nephrons.

So, the correct answer is ' Mineralocorticoids'.

Multiple choice zoology endocrine system and chemical co-ordination adrenal gland thymus and adrenal gland adrenal glands

Cortisol is a 

  1. Mineralocorticoid

  2. Glucocorticoid

  3. Catecholamines

  4. Thymosins
Reveal answer Fill a bubble to check yourself
B Correct answer
Explanation

Our body has one pair of adrenal glands, one at the anterior part of each kidney. The gland is composed of two types of tissues. The centrally located tissue is called the adrenal medulla, and outside this lies the adrenal cortex.
The adrenal cortex can be divided into three layers, called zona reticularis (inner layer), zona fasciculata (middle layer) and zona glomerulosa (outer layer). The adrenal cortex secretes many hormones, commonly called as corticoids. 
 The corticoids, which are involved in carbohydrate metabolism are called glucocorticoids. In our body, cortisol is the main glucocorticoid.

So, the correct option is 'Glucocorticoid'. 

Multiple choice zoology endocrine system and chemical co-ordination adrenal gland thymus and adrenal gland adrenal glands

Besides corticotropin releasing hormone (CRH) which other hormone also stimulate the release of adrenocorticotropic hormone (ACTH) ? 

  1. Glucagon

  2. Insulin

  3. Aldosterone

  4. Epinephrine
Reveal answer Fill a bubble to check yourself
B Correct answer
Explanation

Insulin has been shown to stimulate the release of ACTH in certain physiological contexts, acting alongside CRH. While CRH is the primary stimulator, insulin is also recognized as a factor.