Tag: coordination in human beings- chemical control

Questions Related to coordination in human beings- chemical control

Endocrine glands are those glands which pour their secretion directly into 

  1. Ducts

  2. Substrate

  3. Blood

  4. All of the above


Correct Option: C
Explanation:
Endocrine glands are the ductless glands which secrete their products directly in the blood from where they reach the target organs and affect their functioning and regulation. For example, pituitary gland, hypothalamus, pineal gland etc. On the other hand, the glands which secrete their products through ducts are called exocrine glands. 
So, the correct answer is 'Blood'.

A heterocrine gland is one which

  1. Has two distinct parts

  2. Serves a double function of exocrine and endocrine gland

  3. Produces two types of hormones

  4. Occurs in two places


Correct Option: B
Explanation:
Heterocrine glands are the glands which act both as exocrine and endocrine glands. Exocrine glands are the glands that secrete their products through ducts whereas endocrine glands are the ductless glands which secrete their products directly into the blood. For example, in humans, Pancreas is a heterocrine gland. It secretes insulin hormone into blood and act as endocrine gland and when it secretes digestive enzymes and juice through pancreatic duct, it acts as exocrine gland.
So, the correct answer is 'Serves a double function of exocrine and endocrine gland'.

Which of these is not an endocrine gland? 

  1. Liver

  2. Pancreas

  3. Testes

  4. Thymus


Correct Option: A
Explanation:

Endocrine glands are the ductless glands that secrete their products into bloodstream from where they are carried to the target organs. Pancreas, testes and thymus are endocrine glands as they secrete hormones. Pancreas secrete insulin and glucagon, testes secrete testosterone and thymus secrete thymosin hormone. Liver is not an endocrine gland instead, it is a digestive organ which secretes bile juice which is necessary for emulsification of fats.
So, the correct answer is 'Liver'.

Hormones are produced by 

  1. Apocrine glands

  2. Endocrine glands

  3. Heterocrine glands

  4. Both B and C


Correct Option: D
Explanation:

  • Apocrine glands are generally present in the skin and secrete their products on the skin surface.
  • Endocrine glands are the ductless glands which secrete their products directly into the blood.
  • Heterocrine glands are the glands which act both as exocrine and endocrine glands.For example, in humans, Pancreas is a heterocrine gland. It secretes insulin hormone into blood and act as endocrine gland and when it secretes digestive enzymes and juice through pancreatic duct, it acts as exocrine gland.
Hormones are the chemicals or signalling molecules that are produced by endocrine glands and secreted into blood stream from where they reach their target organs and cause a change in their function and regulation.
Hence, both options B and C are correct.
So, the correct answer is 'Both B and C'.

Secretions of ductless glands is known as 

  1. Hormones

  2. Pheromones

  3. Enzymes

  4. Mucoids


Correct Option: A
Explanation:
A. Hormones are the chemicals or signalling molecules secreted from endocrine glands (ductless glands that secrete their products directly into blood stream from where they are carried to their target organs) which affect the functioning and regulation of target organs.
B. Pheromones are chemicals used by organisms of same species for communication.
C. Enzymes are the biocatalysts that speed up the rate of reaction without getting altered.
D. Mucoids are the fluids secreted from mucosal glands or mucosal membranes.
So, the correct answer is 'Hormones'.

Find out the correct statement. 

  1. Endocrine glands regulate neural activity but not vice versa.

  2. Neurons regulate endocrine activity but not vice versa.

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

  4. Neither hormones control neural activity nor the neurons control endocrine activity.


Correct Option: C
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. Hormones are secreted in the blood from where they reach the target organs and cause changes in their functioning and regulation.
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.'.

Which of these is a mixed gland? 

  1. Thyroid

  2. Pituitary

  3. Adrenal

  4. Pancreas


Correct Option: D
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. Pituitary gland is the master gland that regulates the activity of other endocrine glands and secretes many hormones like growth hormone, follicle stimulating hormone, thyroid stimulating hormone etc.
C. Adrenal gland is present on upper side of kidneys and has two parts, adrenal cortex which secrete glucocorticoids, mineralocorticoids and sexocorticoids and adrenal medulla which secrete adrenaline and nor-adrenaline hormone.
D. Pancreas is a heterocrine gland as it acts both as endocrine and exocrine gland. It secretes insulin hormone into blood and act as endocrine gland and when it secretes digestive enzymes and juice through pancreatic duct, it acts as exocrine gland.
Hence, pancreas is a mixed gland.
So, the correct answer is 'Pancreas'.

How many endocrine glands are located in human brain?

  1. 3

  2. 4

  3. 2

  4. 9


Correct Option: A
Explanation:
There are three endocrine glands which are located in human brain-
1. Hypothalamus is the basal part of diencephalon which is present in forebrain and it regulates a wide spectrum of body functions. It is an anatomical and physiological connection between the nervous system and the endocrine system. It is connected to the pituitary gland by a stalk called infundibulum.
2. Pituitary gland is located in a bony cavity of the sphenoid bone of the skull called sella tursica and is attached to the hypothalamus by a stalk called infundibulum.
3. Pineal gland is located on the dorsal side of forebrain.
So, the correct answer is '3'.

Which one is endocrine? 

  1. Brunner's gland

  2. Crypts of Lieberkuhn

  3. Pars radiata

  4. Juxtaglomerulus


Correct Option: D
Explanation:
A. Brunner's gland are present in small intestine and secrete intestinal juice through ducts.
B. Crypts of Lieberkühn, also known as Paneth cells, are tubular glands present in small intestine and secrete intestinal juice.
C. Pars radiata (medullary rays) are the extensions of medulla into cortex of kidney.
D. Juxtaglomerulus is present in kidneys and consists of juxtaglomerular cells or JG cells that secrete enzyme renin and hormone erythropoietin. Hence, juxtaglomerulus is endocrine (ductless glands) as it secretes a hormone.
So, the correct answer is 'Juxtaglomerulus'.

Which is not involved in endocrine secretion? 

  1. Leydig cell

  2. Lutein cell

  3. Parafollicular cells of thyroid

  4. Kupffer cells


Correct Option: D
Explanation:
Endocrine secretion is the secretion of hormones from endocrine glands which are ductless glands and secrete hormones into blood stream. 
  • Leydig cells are present in testis and secrete testosterone hormone.
  • Lutein cells are present in corpus luteum in ovary and secrete progesterone hormone.
  • Parafollicular cells of thyroid gland secrete calcitonin hormone.
  • Kupffer cells are phagocytic cells in liver that destroy or breakdown red blood cells.
Hence, Kupffer cells are not involved in endocrine secretion.
So, the correct answer is 'Kupffer cells'.