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 biology chemical coordination and integration mechanism of hormone action coordination in human beings- chemical control endocrine system in humans

When the secretion of hormones is under the control of factors or hormones it is called as

  1. Homeostasis

  2. Feedback control

  3. Conjugation

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

When the secretion of hormone is controlled by the factors or other hormones it is called feedback control. For example, homeostasis means keeping the internal environment of the body constant. Hormones help in maintaining internal environment of the body. Thus, the correct answer is option B.

Multiple choice biology chemical coordination and integration mechanism of hormone action coordination in human beings- chemical control endocrine system in humans

Which is an example of negative feedback?

  1. Nursing action stimulates the hypothalamus to release oxytocin that triggers mammary gland milk production.

  2. When the blood becomes dilute, ADH is no longer released from the hypothalamus.

  3. Uterine stretching sends nerve impulses to the hypothalamus that releases oxytocin that triggers uterine contraction.

  4. TRH stimulate the anterior pituitary to release thyroid-stimulating hormone.
Reveal answer Fill a bubble to check yourself
B Correct answer
Explanation

When a high level of particular hormone inhibits their further secretion is called as negative feedback. As the level of water in the blood falls, negative feedback ensures that the amount of ADH rises. As the level of water in the blood rises, negative feedback ensures that the amount of ADH falls. Thus, the correct answer is option B.

Multiple choice biology chemical coordination and integration mechanism of hormone action coordination in human beings- chemical control endocrine system in humans

Feedback control for hormone can be

  1. Positive only

  2. Negative only

  3. Both A and B

  4. None of the above
Reveal answer Fill a bubble to check yourself
C Correct answer
Explanation

When the secretion of hormone is controlled by some factors or other hormones is called as feedback control. It can be both positive and negative. When the hormone secretion is amplified by its own secretion is called as positive feedback. When a high level of particular hormone inhibits their further secretion is called as negative feedback. Thus, the correct answer is option C.

Multiple choice biology chemical coordination and integration mechanism of hormone action coordination in human beings- chemical control endocrine system in humans

Most of the endocrine hormone is controlled by

  1. Negative feedback inhibition

  2. Positive feedback inhibition

  3. Competitive inhibition

  4. All of the above
Reveal answer Fill a bubble to check yourself
A Correct answer
Explanation

Most of the hormones, especially the hormones of the pituitary gland are controlled by the negative feedback inhibition. This system operates between endocrine gland secreting the hormone and the target cells. For example ACTH secreted by the anterior lobe of pituitary stimulates the target cells present in the adrenal gland to produce cortisol. As soon as the concentration of cortisol rises above the set point in the blood stream it acts on pituitary gland to inhibit the secretion of ACTH. Thus option A is the correct answer.

Multiple choice biology chemical coordination and integration mechanism of hormone action coordination in human beings- chemical control endocrine system in humans

How does chemical coordination take place in animals?

  1. Endocrine glands----> hormones-----> blood----> organs / tissues----> biochemical / physiological activity.

  2. Endocrine glands----> hormones----> biochemical / physiological activity-----> blood----> organs / tissues.

  3. Hormones----> biochemical / physiological activity-----> blood----> organs / tissues----> endocrine glands.

  4. Hormones----> biochemical / physiological activity-----> endocrine glands----> blood----> organs / tissues
Reveal answer Fill a bubble to check yourself
A Correct answer
Explanation

Endocrine glands----> hormones-----> blood----> organs / tissues----> biochemical / physiological activity.

Chemical coordination in multicellular organisms take place through the special chemical substances called hormones, which are produced in endocrine glands. These chemicals unlike nerve cells, reach all the cells of the body and bring about desirable changes as instructed by the brain and spinal cord. This is done by using a hormone named adrenaline. It is directly secreted into the blood and carried to different parts of the body. The heart, beats faster to supply more oxygen to our muscles. The breathing rate also increases. All these responses enable the animal body to be ready to face the situation. Such hormones constitute a second way of control and coordination.

Multiple choice biology chemical coordination and integration mechanism of hormone action coordination in human beings- chemical control endocrine system in humans

Feed back mechanism controls

  1. Nervous system

  2. Enzyme production

  3. Time and amount of hormones released by endocrine glands

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

Most hormones are regulated by feedback mechanisms. A feedback mechanism is a loop in which a product feeds back to control its own productions. Most negative feedback loops get involved from hormone feedback mechanisms. Here the time delay occurs and hormones are released.

So, the correct option is 'Time and amount of hormones released by endocrine glands'.

Multiple choice biology chemical coordination and integration mechanism of hormone action coordination in human beings- chemical control endocrine system in humans

Group of hormones which is released with cytoplasmic bounded receptors?

  1. Hypothalamic hormones and epinephrine

  2. Thyroid hormone and estradiol

  3. Insulin and glucagon

  4. GH and MSH
Reveal answer Fill a bubble to check yourself
A Correct answer
Explanation

There are two sets of nerve cells in the hypothalamus that produce hormones.

One set sends the hormones they produce down through the pituitary stalk to the posterior lobe of the pituitary gland where these hormones are released directly into the bloodstream. These hormones are anti-diuretic hormone and oxytocin.
So, the correct option is 'Hypothalamic hormones and epinephrine.

Multiple choice biology chemical coordination and integration mechanism of hormone action coordination in human beings- chemical control endocrine system in humans

A feedback mechanism regulates the action of the 

  1. Hormones

  2. Lipids

  3. Cell division

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

The feedback mechanism is the process wherein the upregulation and downregulation of genes, hormones, homoeostasis and other factors are controlled. For example, if the level of sugar concentration in blood has increased feedback mechanism upregulates the hormone insulin which helps to stabilise the sugar in the blood. 

So, the correct answer is option A.

Multiple choice biology transportation in plants and circulation in animals heart beat cardiac cycle heart, blood vessels and cardiac cycle

The hormone that stimulates heart beat is

  1. Thyroxine

  2. Adrenaline

  3. Glucagon

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

Adrenaline (epinephrine) is the primary hormone released during stress that stimulates the heart to beat faster and with more force. Thyroxine also affects heart rate, but adrenaline is the classic stimulator for immediate heart rate increases.

Multiple choice biology digestive system of human digestive glands liver pancreas

Which one of the following is not secreted by pancreas

  1. Insulin

  2. Glucagon

  3. Renin

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

Renin is an enzyme secreted by the juxtaglomerular cells of the kidney, not the pancreas. Insulin, glucagon, and somatostatin are all produced by the endocrine pancreas.

Multiple choice biology digestive system of human digestive glands liver pancreas

Growth hormone is secreted by

  1. Acidophilic $\alpha$ - cells
  2. Acidophilic $\beta$ - cells
  3. Basophilic $\alpha$ - cells
  4. Basophilic $\beta$ - cells
Reveal answer Fill a bubble to check yourself
A Correct answer
Explanation
Pituitary gland has two parts; adenohypophysis and neurohypophysis. Adenohypophysis has two types of cells, chromophobe cells and chromophil cells. Chromophil cells are divided into acidophilic or alpha cells and basophilic or beta cells depending upon whether they stain with acidic or basic dyes.
Growth hormone (GH) is secreted from acidophilic cells i.e. alpha cells (α) of anterior pituitary. It stimulates body growth and metabolism.
So, the correct answer is 'Acidophilic αα - cells'.
Multiple choice biology digestive system of human digestive glands liver pancreas

Glucagon is produced by 

  1. Peptic cells

  2. Oxyntic cells

  3. Alpha cells

  4. Beta cells
Reveal answer Fill a bubble to check yourself
C Correct answer
Explanation
A. Peptic cells secrete pepsinogen (inactive form of pepsin enzyme that degrades proteins).
B. Oxyntic cells, also known as parietal cells, secrete HCl (Hydrochloric acid) in the stomach.
C. Alpha cells are part of islets of Langerhans in pancreas and secrete glucagon hormone which increases blood sugar level.
D.  Beta cells are part of islets of Langerhans in pancreas and secrete insulin hormone which decreases blood sugar level.
So, the correct answer is 'Alpha cells'.
Multiple choice biology control and coordination in living organisms control of blood glucose endocrine system and hormone hormones in human reproduction testes and ovary parts of the brain kidney

Growth hormone is produced in

  1. Adrenals

  2. Thyroid

  3. Pituitary

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

Growth hormone is released into the bloodstream from the anterior pituitary gland. Growth hormone release is caused by another hormone (growth hormone-releasing hormone), which is released from the hypothalamus and it causes the pituitary gland to release the growth hormone.

Multiple choice biology control and coordination in living organisms control of blood glucose endocrine system and hormone hormones in human reproduction testes and ovary parts of the brain kidney

The follicle stimulating hormone is secreted from

  1. Posterior lobe of pituitary gland

  2. Reproductive gland

  3. Thyroid gland

  4. Anterior lobe of pituitary gland
Reveal answer Fill a bubble to check yourself
D Correct answer
Explanation

Follicle-stimulating hormone (FSH) is a glycoprotein and gonadotropin secreted by the anterior pituitary in response to gonadotropin-releasing hormone (GnRH) released by the hypothalamus. It helps in the development of follicles in female and triggers Sertoli cells to initiate spermatogenesis in the male.

So, the correct answer is option D.