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.

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Human Endocrine System Questions

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. 

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

The hormone that initiates ejection of milk, stimulates milk production and growth of ovarian follicles are respectively known as

  1. PRL, OT and LH

  2. OT, PRL and FSH

  3. LH, PRL and FSH

  4. PRH, OT and LH
Reveal answer Fill a bubble to check yourself
B Correct answer
Explanation
I. Ejection of milk is stimulated by the hormone oxytocin (OT).
II. Milk production is stimulated by the hormone prolactin (PRL).
III. Growth of ovarian follicles is maintained by the hormone Follicle Stimulating Hormone (FSH).
So, the correct answer is 'OT, PRL and FSH'.
Multiple choice female reproductive structure reproductive system of human hormones, homeostasis, and reproduction human physiology biology

The secretion of progesterone by corpus luteum is initiated by

  1. FSH

  2. LH

  3. MSH

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

The luteal phase is marked by the increased concentration of the luteinizing hormone. The LH stimulates the corpus luteum to secrete progesterone which helps in the maintenance of the pregnancy by increasing the thickening of the cell lining of the endometrial wall. 

Thus, the correct answer is option B. 

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

In human adult females oxytocin

  1. stimulates pituitary to secrete vasopressin

  2. causes strong uterine contractions during parturition

  3. is secreted by anterior pituitary

  4. simulates growth of mammary glands.
Reveal answer Fill a bubble to check yourself
B Correct answer
Explanation

In human adult female oxytocin is a hormone released by the pituitary gland (neurohypophysis), that causes contraction of the uterine muscles during labour.

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

Luteinizing hormone is responsible for 

  1. Ovulation and formation of corpus luteum

  2. Controlling activity of corpus luteum

  3. Development of mammary glands

  4. Growth of female reproductive organs
Reveal answer Fill a bubble to check yourself
A Correct answer
Explanation

LH is secreted by anterior pituitary which inhibits secretion of FSH, stimulate maturation and rupture of Graafian follicle and release of ovum. LH also stimulates the formation of corpus luteum (the luteal/secretory phase; days 15-28) from ovulated Graafian follicle which in turn secretes estrogens and progesterone. In absence of implantation, progesterone and estrogens exerts negative feedback control over the anterior pituitary’s secretion of LH and causes degeneration of corpus luteum in the ovary. The lower progesterone level, as caused by disintegration of corpus luteum, results in disintegration of endometrium thereby initiating the next menstrual cycle. Thus, corpus luteum activity is under the regulation of estrogen and progesterone via negative feedback control. LTH (luteotropic hormone/prolactin) is secreted by the anterior pituitary gland and targets mammary gland to stimulate breast development and milk production after baby birth. Estrogens serves to stimulate the growth of the uterus and the vagina, is necessary for egg maturation as well as for the development of the secondary sex characteristics in females. Thus, the correct answer is A. 

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

Gonadotropic hormone is secreted by

  1. Adenohypophysis of the pituitary gland

  2. Parathyroids

  3. Interstitial cells of the testes

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

Gonadotropin is secreted from the anterior pituitary gland and it acts on the gonads (i.e., the ovaries or testes). The anterior pituitary contains five types of endocrine cell, and they are defined by the hormones they secrete-somatotropes (GH); Lactotropes (PRL); gonadotropes (LH and FSH); corticotrophs (ACTH) and thyrotropes (TSH). Gonadotrophs, cells that constitute about 10 percent of the pituitary gland, secrete two primary gonadotropins: luteinizing hormone (LH) and follicle-stimulating hormone (FSH). Secretion of LH and FSH is low in both males and females prior to puberty

So, the correct answer is 'adenohypophysis of the pituitary gland'

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

Follicle-stimulating hormone (FSH)

  1. Is secreted by females but not males

  2. Stimulates the seminiferous tubules to produce sperm

  3. Secretion is controlled by gonadotropin releasing hormone (GnRH)

  4. Both (B) and (C)
Reveal answer Fill a bubble to check yourself
D Correct answer
Explanation

Follicle stimulating hormone is produced by the pituitary gland. It regulates the functions of both the ovaries and testes. Follicle stimulating hormone is one of the gonadotropic hormones, the other being a luteinising hormone. FSH enters the testes, stimulating the Sertoli cells, which help to nourish the sperm cells that the testes produce, to begin facilitating spermatogenesis. The Sertoli cell is a kind of sustentacular cell which serves as a “nurse” cell of the testes and which is part of a seminiferous tubule.

So the correct option is 'both (b) and (c)'.

Multiple choice zoology control and coordination in living organisms pineal gland pituitary gland and pineal gland pineal gland and thymus

The recently discovered hormone, melatonin is derived from serotonin which is synthesised by

  1. Adrenal gland

  2. Pineal gland

  3. Thymus gland

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

The pineal gland is a small endocrine gland in the vertebrate brain. It produces melatonin, a serotonin derived hormone, that affects the modulation of sleep patterns in both seasonal and circadian rhythms.

Multiple choice zoology control and coordination in living organisms pineal gland pituitary gland and pineal gland pineal gland and thymus

Serotonin is secreted from

  1. $\alpha $- cells
  2. $\beta $- cells
  3. $\delta $- cells

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

Serotonin is the hormone that contributes the feeling of well being and happiness in animals including humans. It is basically derived from tryptophan and is located in the gastrointestinal tract (GI tract), blood platelets and central nervous system. 90% of the total serotonin is primarily located in GI tract in Enterochromaffin cells and used for regulation of intestinal movements. Hence, answer D is correct.