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 hormones coordination in human beings- chemical control endocrine system in humans

Choose the correct answer from the alternatives given.
Which hormone stimulates secretion of milk in mammary glands?

  1. TSH

  2. Prolactin

  3. Vasopressin

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

(A) Thyroid stimulating hormone (TSH) promotes growth and function if thyroid gland. 

(B) Prolactin hormone stimulates lactation (milk production) and has a direct effect on the breasts immediately after parturition.
(C) Vasopressin or antidiuretic hormone (ADH) acts mainly at the kidney and stimulates resorption of water and electrolytes by the distal tubules and thereby reduce the loss of water through urine (diuresis). 
(D) Thyroxine is primarily responsible for regulation of metabolism.
So the correct answer is vasopressin.

Multiple choice biology chemical coordination and integration hormones coordination in human beings- chemical control endocrine system in humans

Choose the correct answer from the alternatives given.
Which of the following is not an accurate statement about hormones?

  1. Hormones are chemical messengers that travel to target cells through the circulatory system

  2. Hormones often regulate .homeostasis through antagonistic functions

  3. Hormones of the same chemical class usually have the same general function

  4. Hormones are often regulated through feedback loops
Reveal answer Fill a bubble to check yourself
C Correct answer
Explanation

Hormones are nonnutrient chemicals which act as intercellular messengers and are produced in trace amounts. All hormones produce their specific effects on target tissue/cells by binding to the specific proteins called as hormone receptors. The normal functioning of endocrine glands and the level of hormones in the body needs to be regulated. This is possible through a feedback mechanism.

So the correct answer is hormones of the same chemical class usually have the same general function.

Multiple choice biology chemical coordination and integration hormones coordination in human beings- chemical control endocrine system in humans

Choose the correct answer from the alternatives given.
Second messengers include:

  1. steroid hormones

  2. cyclic AMP

  3. protein hormones

  4. both (a) and (b)
Reveal answer Fill a bubble to check yourself
B Correct answer
Explanation

Hormones which interact with membrane-bound receptors normally do not enter the target cell but generate second messengers (eg, cyclic AMP, IP3, Calcium Ions etc) which in turn regulate cellular metabolism. Hormones which interact with intracellular receptors (eg, steroid hormones, iodothyronines, etc) mostly regulate gene expressions or chromosome function by the interaction of hormone receptor complex with the genome. 

So the correct answer is cyclic AMP.

Multiple choice biology chemical coordination and integration hormones coordination in human beings- chemical control endocrine system in humans

Choose the correct answer from the alternatives given.
Which organ does not synthesize hormones?

  1. Heart

  2. Adrenal cortex

  3. Anterior pituitary

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

Endocrine gland lack ducts and are called ductless glands. Their secretions are called hormones. Adrenal cortex secrets many hormones commonly called as corticoids. Anterior pituitary secretes many hormones such as GH, PRL, TSH, ACTH etc. The pineal gland secretes three hormones namely, melatonin, serotonin, adrenoglomerulotropin.

So the correct answer is the heart. 

Multiple choice biology chemical coordination and integration hormones coordination in human beings- chemical control endocrine system in humans

Choose the correct answer from the alternatives given.
Human sex hormones are classified as:

  1. amino acids

  2. lipids

  3. triacyiglycerols

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

Human sex hormone is steroid hormones. The natural steroid hormones are generally synthesized from cholesterol in the gonads and adrenal glands. These forms of hormones are lipids. 

So the correct answer is lipids.

Multiple choice biology chemical coordination and integration hormones coordination in human beings- chemical control endocrine system in humans

Choose the correct answer from the alternatives given.
Which of the following hormones is called an antidiuretic hormone?

  1. Glucagon

  2. Prolactin

  3. Vasopressin

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

(A) Glucagon acts mainly on the liver cells and stimulates glycogenolysis resulting in increased blood sugar (hyperglycemia).

(B) Prolactin regulates the growth of the mammary glands and formation of milk in them. 
(C) Vasopressin or antidiuretic hormone (ADH) acts mainly at the kidney and stimulates resorption of water and electrolytes by the distal tubules and thereby reduce the loss of water through urine (diuresis). 
(D) Cortisone is the main glucocorticoid.
So the correct answer is vasopressin.

Multiple choice biology chemical coordination and integration hormones coordination in human beings- chemical control endocrine system in humans

Which of the following statements is correct in relation to the endocrine system?

  1. Non-nutrient chemicals produced by the body in trace amount that act as intercellular messenger are known as hormones

  2. Releasing and inhibitory hormones are produced by the pituitary gland

  3. Adenohypophysis is under direct neural regulation of the hypothalamus

  4. Organs in the body like gastrointestinal tract, heart, kidney and liver to not produce any hormone
Reveal answer Fill a bubble to check yourself
A Correct answer
Explanation

The endocrine system consists of organ, tissue and cells that produce a small amount of non-nutrient chemicals which sends signals to other cells or acts as an intercellular messenger. These chemicals are known as hormones which are transported to their target site through blood.

So the correct answer is 'Non-Nutrient chemicals produced by the body in trace amount that acts as intercellular messenger are known as hormones'.

Multiple choice biology chemical coordination and integration hormones coordination in human beings- chemical control endocrine system in humans

Which of the following statements regarding hormones is incorrect?

  1. Hormones are non-nutrient chemicals which acts as intercellular messengers

  2. Hormones are molecules of low molecular weight and are produced in traces

  3. Hormones provide energy and also effect growth and metabolic activities of target cell

  4. Many hormones are produced in inactive form
Reveal answer Fill a bubble to check yourself
C Correct answer
Explanation

Hormones do not provide energy or building materials but they effect growth, differentiation and metabolic activities of their target cell.

Multiple choice biology chemical coordination and integration hormones coordination in human beings- chemical control endocrine system in humans

Choose the correct answer from the alternatives given.
Steroid hormones mediate their action by:

  1. activating adenylate cydase

  2. activating gene expression

  3. binding to the surface membrane of the cells

  4. inhibiting an enzyme
Reveal answer Fill a bubble to check yourself
B Correct answer
Explanation

Steroid hormones and thyroid hormones do not bind to the cell surface receptors. Being lipid soluble, these are able to enter the cells and their nuclei and influence the gene action. The hormone binds to the receptors forming a hormone-receptor complex. It binds to the transcription factors that in turn to DNA and a particular gene is activated. Their transcription leads to the synthesis of a specific protein to influence the metabolism of the recipient cell. Thus, the peptide hormones activate existing enzymes in the cell while steroid hormones bring about the synthesis of new enzymes.

So the correct answer is activating gene expression.

Multiple choice biology chemical coordination and integration hormones coordination in human beings- chemical control endocrine system in humans

Which of these is a correct statement? 

  1. Neurons regulate endocrine activity but not vice versa.

  2. Endocrine glands regulate neural activity and nervous system regulates endocrine glands.

  3. Neither hormones control neural activity nor neurons control endocrine activity.

  4. Endocrine glands regulate neural activity but not vice versa.
Reveal answer Fill a bubble to check yourself
B Correct answer
Explanation

  • Nervous system is a coordinated network of nerve cells and fibres by which nerve impulses are transmitted throughout the body.
  • Endocrine system consists of glands that produce hormones.
In our body, nervous system and endocrine system jointly integrate all the activities as nervous system directs endocrine system to secrete hormones that act on the target organs.
So, the correct answer is 'Endocrine glands regulate neural activity and nervous system regulates endocrine glands.'.

Multiple choice biology chemical coordination and integration hormones coordination in human beings- chemical control endocrine system in humans

Consider the following statements (a-d) and select the option which includes the correct ones only.
(a) The thyroid hormone plays an important role in the maintenance of the basal metabolic rate & erythropoiesis.
(b) Glucocorticoids inhibit inflammatory reactions by suppressing the immune system and promote erythropoiesis.
(c) Androgens promote development, maturation & function of the male sex organs as well as erythropoiesis.
(d) The gastrointestinal tract not only secretes gastric inhibitory peptide but also promotes the formation of RBCs.

  1. 4

  2. 3

  3. 2

  4. 1
Reveal answer Fill a bubble to check yourself
A Correct answer
Explanation
In the given question, all the statements are correct as they all mention the correct function and effect of their respective hormones.
So, the correct answer is '4'.
Multiple choice zoology control and coordination in living organisms mechanism of hormone action coordination in human beings- chemical control endocrine system in humans

Steroid hormones transmit their information by 

  1. Stimulating the receptors present on cellmembrane

  2. Entering into the cell and modifying cellular contents

  3. Entering into the cell and modifying nuclear organisation

  4. The help of an intracellular second messenger
Reveal answer Fill a bubble to check yourself
C Correct answer
Explanation

There are specific receptors for the binding of hormones. Steroid hormones have nuclear receptors. These steroid hormones are composed of cholesterol a dare hydrophobic in nature. They enter the cells through cell membranes. They move towards the nucleus and bind to the respective receptor. They have the activity like repression, initiation or transcription of certain genes and products. 

So, the correct answer is option C. 

Multiple choice zoology endocrine system and chemical co-ordination mechanism of hormone action coordination in human beings- chemical control endocrine system in humans

Read the following carefully to give the correct answer 

  1. Protein hormone interact with the intra cellular receptor

  2. Iodothyronine hormone generate secondary messenger after interaction with receptor

  3. Hormone is a cell specific

  4. Somatostatin hormone secrete only by hypothalamus
Reveal answer Fill a bubble to check yourself
A Correct answer
Multiple choice zoology endocrine system and chemical co-ordination mechanism of hormone action coordination in human beings- chemical control endocrine system in humans

Tyrosine act as a precursor for which of the following hormones?

  1. Thyroid

  2. Adrenal

  3. Prolactin

  4. FSH
Reveal answer Fill a bubble to check yourself
A Correct answer
Explanation
  • Thyroxine (3,5,3',5'-tetraiodothyronine) is the thyroid hormone produced by follicular cells of the thyroid gland.
  • Thyroxine hormone is produced in the thyroid gland from tyrosine and iodine.
  • Hence the precursor for the synthesis of thyroid hormone is amino acid Throne.
  • Tyrosine (symbol Tyr or Y) or 4-dihydroxyphenylalanine is one of the 20 standard amino acids.
  • So, the correct answer is 'Thyroid'.
Multiple choice zoology endocrine system and chemical co-ordination mechanism of hormone action coordination in human beings- chemical control endocrine system in humans

The signal transduction of steroid hormone across cell is through

  1. Binding of hormone to the cytoplasmic receptor and the complex binds to hormone response element on DNA with promoter DNA

  2. Binding of hormone to the transmembrane receptor which initiates the production of second messenger that activates enzymes which further activates transcription factors

  3. Binding of hormone to the transmembrane receptor which diffuse inside the cell cytoplasm and then activates the enzyme necessary for the activation of transcription factors

  4. Binding of hormone to the cytoplasmic receptor that initiates the production of second messenger which activates enzymes that further activates transcription factors
Reveal answer Fill a bubble to check yourself
C Correct answer
Explanation

Steroid hormones, i.e., androgens, estrogens, glucocorticoids, mineralocorticoids, and progestins, bind with high affinity to their respective steroid hormone receptors (SR).


Steroid hormone receptors are found in the nucleus, cytosol, and also on the plasma membrane of target cells. They are generally intracellular receptors (typically cytoplasmic or nuclear) and initiate signal transduction for steroid hormone which leads to changes in gene expression over a time period of hours to days.

So the correct answer is ' binding of hormone to the transmembrane receptor which diffuse inside the cell cytoplasm and then activates the enzyme necessary for the activation of transcription factors'.