Biology · General Awareness

Human Endocrine System

1,395 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 excretion and osmoregulation micturition urine and urine formation urine formation

Urine output is reduced by

  1. Oxytocin

  2. ACTH

  3. LH

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

The distal convoluted tubule (DCT) reacts to the amount of anti-diuretic hormone (ADH) or vasopressin in the blood. The more ADH is present in the blood, the more water is reabsorbed into it. This happens because the presence of ADH in the blood causes the cells in the DCT to become more permeable to water, therefore they allow more water to pass from the tubular fluid back into the blood. This results in more concentrated urine.

Multiple choice zoology excretion and osmoregulation micturition urine and urine formation urine formation

Which of the following is responsible for excretion of dilute urine?

  1. More secretion of insulin

  2. Less secretion of vasopressin

  3. More secretion of aldosterone

  4. Less secretion of glucagon
Reveal answer Fill a bubble to check yourself
B Correct answer
Explanation

The more ADH is present in the blood, the more water is reabsorbed into it. This happens because the presence of ADH in the blood causes the cells in the last section of the DCT to become more permeable to water, therefore they allow more water to pass from the tubular fluid back into the blood. This results in more concentrated urine.

Multiple choice zoology excretion and osmoregulation micturition urine and urine formation urine formation

Vasopressin is related with

  1. Dilution of urine

  2. Quick digestion

  3. Concentration of urine

  4. Slow heart beat
Reveal answer Fill a bubble to check yourself
C Correct answer
Explanation

The more ADH is present in the blood, the more water is reabsorbed into it. This happens because the presence of ADH in the blood causes the cells in the DCT to become more permeable to water, therefore they allow more water to pass from the tubular fluid back into the blood. This results in more concentrated urine.

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

Given are four statements(A-D) each with one or two blanks. Select the option which correctly fills up the blank in any two statements.
(A) Thymus secretes _____(i) which help in differentiation of _(ii).
(B) The adrenal medulla secretes _(i) which stimulates the breakdown of _(ii) to increase the blood glucose concentration during emergency situations.
(C) The Leydig's cells or __(i) present in the intertubular spaces in testis, produce a group of hormone called __(ii).
(D) Thyroid gland secretes ___(i) and triiodothyronine which contain ______(ii)

  1. (A)-(i) melatonin, (ii) T-lymphocytes, (B)- (i) adrenaline, (ii) fat

  2. (B)- (i) catecholamine, (ii) glycogen, (C)-(i) interstitial cells, (ii) glycogen

  3. (B)-(i) catecholamine, (ii) glycogen, (D)- (i) thyroxine, (ii) iodine

  4. (D)- (i) parathyroid hormone, (ii) calcium, (A)-(i) thymosin, (ii) B- lymphocytes
Reveal answer Fill a bubble to check yourself
C Correct answer
Explanation
The adrenal medulla secretes catecholamine  which stimulates the breakdown of glycogen to increase the blood glucose concentration during emergency situations.
Thyroid gland secretes thyroxine and triiodothyronine which contain iodine.
So, the correct option is '(B)-(i) catecholamine, (ii) glycogen, (D)-(i) thyroxine, (ii) iodine'
Multiple choice zoology endocrine system and chemical co-ordination thymus thymus gland pineal gland and thymus

Which of the following hormone is correctly matched with it's source and function?

  1. Vasopressin - Anterior pituitary - Induces reabsorption of water in nephron

  2. Oxytocin - Anterior pituitray - Contraction in uterine muscles during birth (parturation)

  3. Thymosin - Thymus - Helps in differentiation of T - Lymphocyte
  4. Glucagon - Pancreatic $ \alpha $ cells- Induces the uptake of utilization of glucose inside cells
Reveal answer Fill a bubble to check yourself
C Correct answer
Explanation

The thymus gland, located behind the sternum and between lungs, is only active until puberty. After puberty, the thymus starts to slowly shrink and become replaced by fat. Thymosin is the hormone of the thymus, and it stimulates the differentiation of disease-fighting T cells.

So, the correct answer is 'Thymosin - Thymus - Helps in the differentiation of T - Lymphocyte'.

Multiple choice zoology plants and animal hormones thymus thymus gland pineal gland and thymus

Thymosin hormone is secreted by 

  1. Thyreid

  2. Thymus

  3. Parathyroid

  4. Hypothalamus
Reveal answer Fill a bubble to check yourself
B Correct answer
Explanation
A. Thyroid gland is situated between the trachea and larynx in the neck and secretes thyroxine hormone which increases oxygen consumption by metabolically active tissues.
B. Thymus gland is associated with the development of immune system and present on the dorsal side of heart. It secretes thymosin hormone which plays an important role in the differentiation of T-lymphocytes.
C. Parathyroid gland is present in the form of four small pouches which are embedded in the posterior surface of lobes of thyroid gland. This gland secretes parathormone which increases calcium reabsorption from the bones and causes mobilisation of calcium in the blood.
D. Hypothalamus is present in the forebrain. This gland secretes hormones that regulate the synthesis and secretion of hormones of pituitary gland. 
So, the correct answer is 'Thymus'.
Multiple choice zoology plants and animal hormones thymus thymus gland pineal gland and thymus

Which of these is the correct combination for gland, hormone and its function?

  1. Anterior pituitary - oxytocin - contraction of uterine muscles

  2. Anterior pituitary - vasopressin - induces reabsorption of water in nephron

  3. Thymus - thymosin - proliferation of T-lymphocytes
  4. $\alpha$-cells - glucagon - uptake of glucose by cells
Reveal answer Fill a bubble to check yourself
C Correct answer
Explanation
A. Oxytocin is secreted from the posterior pituitary and helps in the contraction of uterus during childbirth and also stimulates release of milk from mammary glands i.e. lactation.
B. Vasopressin or Anti diuretic hormone (ADH), is secreted from the posterior part of pituitary gland. This hormone increases reabsorption of water in kidneys and this results in decreased rate of urine production.
C. Thymus gland is associated with the development of immune system and present on the dorsal side of heart. It secretes thymosin hormone which plays an important role in the differentiation of T-lymphocytes.
D. Glucagon is secreted from αα-cells of islets of Langerhans of pancreas. It increases blood sugar level by stimulating glycogenolysis (i.e. break down of glucose) and gluconeogenesis (synthesis of glucose).
Hence, option C is the correct combination for gland, hormone and its function.
So, the correct answer is 'Thymus - thymosin - proliferation of T-lymphocytes'.
Multiple choice zoology plants and animal hormones thymus thymus gland pineal gland and thymus

Which of the following helps in differentiation of cells of immune system?

  1. Cortisol

  2. Thyroxine

  3. Thymosin

  4. Steroid
Reveal answer Fill a bubble to check yourself
C Correct answer
Explanation
A. Cortisol is secreted by adrenal cortex of adrenal gland. It produces anti-inflammatory reactions and suppresses the immune response.
B. Thyroxine is secreted by thyroid hormone. It controls basal metabolic rate and physical growth.
C. Thymosin is secreted by thymus gland. It plays a major role in the differentiation of T -lymphocytes which provide cell-mediated immunity.
D. Steroids are secreted by adrenal cortex of adrenal medulla. Example aldosterone, cortisol, androgens.
So, the correct answer is 'Thymosin'.
Multiple choice zoology plants and animal hormones thymus thymus gland pineal gland and thymus

Which of the following do not play any role in calcium balance in the human body?

  1. Vitamin D

  2. Parathyroid hormone

  3. Thyrocalcitonin

  4. Thymosin
Reveal answer Fill a bubble to check yourself
D Correct answer
Explanation
Thymosin is a hormone released by the thymus. It has a major role in the maturation of the T lymphocytes. It has no role in maintaining the calcium balance in the body.
Thus, the correct answer is 'Thymosin.'
Multiple choice zoology molecular basis of inheritance genome projects human genome project human genome project and dna fingerprinting

The appropriate description of animal hormones is _____________.

  1. Have size smaller than 5 kDa

  2. Comprise of proteins only

  3. Comprise of lipid molecule only

  4. Are pour directly into the blood
Reveal answer Fill a bubble to check yourself
D Correct answer
Explanation

Animal hormones are chemical messengers produced by endocrine glands. A defining characteristic is that they are secreted directly into the bloodstream to reach target organs.

Multiple choice female reproductive structure reproductive system of human hormones, homeostasis, and reproduction human physiology biology

Estrogen is secreted by

  1. Liver

  2. Spleen

  3. Ovaries

  4. Pituitary
Reveal answer Fill a bubble to check yourself
C Correct answer
Explanation
  • Estrogen is secreted by follicles on the ovaries and is also secreted by the corpus luteum after the egg has been released from the follicle and from the placenta.
  •  Follicle-stimulating hormone (FSH) stimulates the ovarian production of estrogens by the granulosa cells of the ovarian follicles and corpora lutea.
  • Hence estrogen is secreted by Ovaries.
  • So, the correct answer is 'Ovaries'.
Multiple choice female reproductive structure reproductive system of human hormones, homeostasis, and reproduction human physiology biology

Ovulation hormone is 

  1. FSH

  2. ICSH

  3. LH

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

The average length of the menstrual cycle is about 28 days. By convention the days of the cycle are numbered from the beginning of the menstrual phase of the menstrual cycle, which usually lasts about 4 days. This is followed by the proliferative phase (about 10 days), then by the secretory phase (about 14 days). 

The secretion of gonadotropins (LH and FSH) increases gradually during the follicular phase, and stimulates follicular development as well as secretion of estrogens by the growing follicles. Both LH and FSH attain a peak level in the middle of cycle (about 14th day). Rapid secretion of LH leading to its maximum level during the mid-cycle is called as LH surge, induces rupture of Graafian follicle and thereby the release of ovum (ovulation).

Multiple choice female reproductive structure reproductive system of human hormones, homeostasis, and reproduction human physiology biology

In mammals the female secondary sexual characters are developed mainly by the hormone

  1. Relaxin

  2. Estrogens

  3. Progesterone

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

Estrogens are the primary female sex hormones. They promote the development of female accessory/secondary sexual characteristics, such as breasts, and are also involved in the thickening of the endometrium and other aspects of regulating the menstrual cycle.

Multiple choice female reproductive structure reproductive system of human hormones, homeostasis, and reproduction human physiology biology

Estrogen is secreted by

  1. Ovary

  2. Membrana granulosa of Graafian follicle

  3. Germinal epithelium of ovary

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

A cross section of ovary reveals a cortex and a vesicular medulla. The cortex contains round epithelial vesicle or follicles; follicles are actual center of ovum production or oogenesis. Each primary oocyte is surrounded by a layer of granulosa cells and then called the primary follicle. Follicles are usually located directly beneath the cortex of the ovary. They secret estrogen. But once they begin to mature, they migrate towards the inner medulla. The medulla consists of layers of soft stromal tissue. The stromal tissue contains rich supply of blood vessels, nerves and lymph vessels.

Multiple choice female reproductive structure reproductive system of human hormones, homeostasis, and reproduction human physiology biology

Progesterone is secreted by

  1. Corpus aorta

  2. Corpus albicans

  3. Corpus luteum

  4. Corpus callosum
Reveal answer Fill a bubble to check yourself
C Correct answer
Explanation

Progesterone is produced in large amounts in the ovaries by the corpus luteum. It begins producing at the stage of puberty and produced till menopause. It is involved in the menstrual cycle, pregnancy and embryogenesis of humans and other species.