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 biology life processes: control and coordination structure and function of brain human brain nervous and endocrine system in humans

Endorphin release is stimulated by

  1. Sleep

  2. Endogenous rhythm

  3. Exercise

  4. Carotene-rich food
Reveal answer Fill a bubble to check yourself
C Correct answer
Explanation
Endomorphins are the chemical substance which is present in the neurons. It helps in the perception of pain, reactions to stress, and cardiovascular, respiratory and digestive functions. They are produced within the body so they are known as endogenous. They specifically work by binding to opoid receptors which are mainly found in nervous system and regulates the motor neurons which helps to coordinate the physical activity.
So, the correct answer is option C.
Multiple choice biology life processes: control and coordination structure and function of brain human brain nervous and endocrine system in humans

Endorphin is produced by

  1. Pituitary

  2. Hypothalamus

  3. Medulla oblongata

  4. Both A and B
Reveal answer Fill a bubble to check yourself
D Correct answer
Explanation
Endomorphins are the chemical substance which is present in the neurons. It helps in the perception of pain, reactions to stress, and cardiovascular, respiratory and digestive functions. They are produced within the body so they are known as endogenous. They specifically work by binding to opoid receptors which are mainly found in nervous system and regulates the motor neurons which helps to coordinate the physical activity. The hypothalamus activates the pituitary to release ACTH which also stimulates the release of endomophins.
So, the correct answer is option D.
Multiple choice biology reproduction in living organisms regeneration asexual modes of reproduction reproduction in animals

Factors controlling regeneration seem to be

  1. Neural

  2. Hormonal

  3. Both neural and hormonal

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

Formation of new cells or tissues from injured parts of the body is called Regeneration. It is controlled by epithelial cover, neural trophic factor, and hormones like adrenal and pituitary glands.

So, the correct option is ‘Both neural and hormonal’.

Multiple choice biology control and coordination in living organisms parathyroid gland thyroid and parathyroid gland thyroid, parathyroid and thymus gland

Parathormone influences calcium absorption in the small intestine by regulating the metabolism of

  1. Vitamin C

  2. Vitamin D
  3. Vitamin $B _{6}$

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

Vitamin D increases blood concentrations of calcium. It is generated through the activity of parathyroid hormone within the kidney. The most important effect of vitamin D is to facilitate absorption of calcium from the small intestine. Along with thyroid hormone, vitamin D also enhances fluxes of calcium out of bone.

Multiple choice biology control and coordination in living organisms parathyroid gland thyroid and parathyroid gland thyroid, parathyroid and thymus gland

Parathormone regulates

  1. Blood calcium level

  2. Blood calcium and phosphate level

  3. Body temperature

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

Parathyroid hormone (PTH), parathormone or parathyrin, is secreted by the chief cells of the parathyroid glands. It acts to increase the concentration of calcium ($Ca^{2+}$) in the blood. Parathormone also inhibits the reabsorption of phosphate by the kidney tubules, thereby decreasing serum phosphate concentrations. This potentiates the ability of parathormone to increase serum calcium concentrations because fewer insoluble calcium-phosphate complexes are formed when serum phosphate concentrations are low.

Multiple choice biology control and coordination in living organisms parathyroid gland thyroid and parathyroid gland thyroid, parathyroid and thymus gland

The hormones responsible for regulation of calcium and phosphorous metabolism is secreted by

  1. Pancreas

  2. Thyroid

  3. Thymus

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

Parathormone of parathyroid gland reduces the blood phosphate level while increases the blood calcium level. Antagonistic functions of insulin and glucagon hormones of pancreas maintain the homeostasis of blood glucose level. Thyroid hormones regulate the metabolic rate of the body. Thymus hormone serves in the differentiation of lymphocytes present inside the lobules. Thus, the correct answer is D.

Multiple choice biology control and coordination in living organisms parathyroid gland thyroid and parathyroid gland thyroid, parathyroid and thymus gland

Parathyroid hormone

  1. Is produced by the thyroid gland

  2. Is released when blood calcium levels fall

  3. Stimulates osteoblasts to lay down new bone

  4. Stimulates calcitonin release
Reveal answer Fill a bubble to check yourself
B Correct answer
Explanation

Parathyroid hormone is secreted by the parathyroid glands and is the most important regulator of calcium levels in the blood and within the bones. Parathyroid hormone is mainly controlled by the negative feedback of calcium levels in the blood to the parathyroid glands. Low calcium levels in the blood stimulate parathyroid hormone secretion, whereas high calcium levels in the blood prevent the release of parathyroid hormone.

Multiple choice biology control and coordination in living organisms parathyroid gland thyroid and parathyroid gland thyroid, parathyroid and thymus gland

Parathormone is secreted during 

  1. Increased blood calcium level

  2. Decreased blood calcium level

  3. Increased blood sugar level

  4. Decreased blood sugar level
Reveal answer Fill a bubble to check yourself
B Correct answer
Explanation

Parathyroid hormone is mainly controlled by the negative feedback of calcium levels in the blood to the parathyroid glands. Low calcium levels in the blood stimulate the parathyroid hormone secretion, whereas high calcium levels in the blood prevent the release of parathyroid hormone. 

Multiple choice biology plants and animal hormones parathyroid gland thyroid and parathyroid gland thyroid, parathyroid and thymus gland

Hormone responsible for regulation of calcium and phosphorus homeostasis is secreted by

  1. Pituitary

  2. Parathyroids

  3. Thymus

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

The parathyroid glands are small endocrine glands in the neck that produce parathyroid hormone. Humans have four parathyroid glands, which are usually located behind the thyroid gland and in rare cases, within the thyroid gland or in the chest. Parathyroid glands control the amount of calcium in the blood and within the bones.

Multiple choice biology plants and animal hormones parathyroid gland thyroid and parathyroid gland thyroid, parathyroid and thymus gland

Which of the following statements is correct for 'parathormone'?

  1. It increases blood calcium level and decreases calcium store of the bone

  2. It decreases blood calcium level and increased calcium store of the bone

  3. It increases blood glucose level and decreases calcium store of the bone

  4. It decreases blood glucose level and increases calcium store of the bone
Reveal answer Fill a bubble to check yourself
A Correct answer
Explanation

Parathormone (PTH) increases blood calcium levels by stimulating bone resorption (releasing calcium from bone) and increasing calcium reabsorption in the kidneys.

Multiple choice biology plants and animal hormones parathyroid gland thyroid and parathyroid gland thyroid, parathyroid and thymus gland

In which of the following options, hormone is not matching with its source and function?

  1. Hormone- Glucocorticoids, Source-Adrenal cortex, Function-Produces anti-inflammatory reactions

  2. Hormone-Vasopressin, Source-Posterior pituitary, Function-Stimulates resorption of water and electrolytes
  3. Hormone-Parathyroid hormone, Source-thyroid, Function-Decreases the blood $Ca^{2+}$ level

  4. Hormone-Melatonin, Source-Pineal gland, Function-Maintains sleep-wake cycle
Reveal answer Fill a bubble to check yourself
C Correct answer
Explanation

Hormone released by the parathyroid gland is parathyroid hormone also called parathormone or parathyrin, this hormone regulates the Ca$^{+2}$ concentration in the serum by acting upon bone, kidney and intestine.

So, the correct answer is 'Hormone-Parathyroid hormone, Source-thyroid, Function-Decreases the blood Ca$^{+2}$ level'

Multiple choice biology plants and animal hormones parathyroid gland thyroid and parathyroid gland thyroid, parathyroid and thymus gland

The blood calcium level is lowered by the deficiency of.

  1. Thyroxine

  2. Calcitonin

  3. Parathormone

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

Parathormone secreted by parathyroid gland regulates the level of calcium in the blood. It stimulates the release of calcium from the bones into the blood, increases calcium absorption from the intestine into the blood and it also increases calcium reabsorption from the nephrons into the blood. Therefore, its deficiency leads to low blood calcium level.

Multiple choice biology plants and animal hormones parathyroid gland thyroid and parathyroid gland thyroid, parathyroid and thymus gland

Parathormone influences calcium absorption in the small intestine by regulating the metabolism of 

  1. Vitamin C

  2. Vitamin D
  3. Vitamin ${ B } _{ 6 }$

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

The kidney processes Vitamin D into calcitriol, the active form that is most effective in assisting intestinal absorption. This process is stimulated by parathyroid hormone. Vitamin D is an important co-factor in the intestinal absorption of calcium, as it increases the number of calcium binding proteins, involved in calcium absorption through the apical membrane of enterocytes in the small intestine.

Multiple choice biology plants and animal hormones parathyroid gland thyroid and parathyroid gland thyroid, parathyroid and thymus gland

Name the two hormones that regulates blood calcium levels in the body

  1. Insulin and glucagon

  2. Thyroxine and estrogen

  3. Thyrocalcitonin and parathyroid hormone

  4. Prolactin and oxytocin
Reveal answer Fill a bubble to check yourself
C Correct answer
Explanation

Thyrocalcitonin (TCT) is secreted when calcium level in blood is high. It then lowers the levels by suppressing  release of calcium ions from bones. Whereas parathyroid hormone increases the blood calcium level by increasing calcium absorption from intestine and mobilising calcium from bones to blood.