Tag: excretory system in human

Questions Related to excretory system in human

Which one is an accessory excretory organ?

  1. Liver

  2. Stomach

  3. Intestine

  4. Heart


Correct Option: A
Explanation:
An organ that helps in a process but is not part of the tract related to that biological process is called as accessory organ.
For instance, salivary glands, liver, gallbladder, and pancreas are not part of the digestive tract, but they have a role in digestive activities. The accessory digestive organs are the tongue, salivary glands, pancreas, liver, and gallbladder.
Hence, the answer is 'Liver'

The urinary bladder is muscular and is under ............ control.

  1. Muscular

  2. Mechanical

  3. Nervous

  4. Hormonal


Correct Option: C
Explanation:

The urinary bladder is made up of several detrusor muscles which mainly expands and contracts by the signals received by the autonomic nervous system. Parasympathetic nerves from the S2, S3 and S4 levels of spinal cord cause the upper part of the bladder to contract and bladder neck to relax, assisting in the process of micturition (urination). Sympathetic nerves from the $T _{11}$-$L _2$ levels of spinal cord do the opposite, causing the upper section of the bladder to relax and the bladder neck to contract, ensuring urine storage.

So, the correct answer is option C.

Which one is not supplied exclusively with involuntary muscles?

  1. Iris

  2. Gland ducts

  3. Urethra

  4. Coats of blood vessels


Correct Option: C
Explanation:

Iris is supplied by involuntary muscles which contract or relax in response to photo stimuli. Gland ducts have muscles in their walls and in the form of sphincters which are involuntary. Coats of blood vessels also have a muscle layer sandwiched between two other layers. Urethra has two sphincters of which one is involuntary and one is voluntary. Hence, urethra is not exclusively supplied with involuntary muscles.

The wall of urinary bladder has a thick layer of smooth muscle called

  1. Dartos

  2. Detrusor

  3. Deltoid

  4. Depressor


Correct Option: B
Explanation:

a) Dartos muscle is a muscle present in the scrotal sac. 

b) Deltoid muscle is a muscle of the upper arm. 
c) Depressor muscle is a facial muscle. 
d) Detrusor smooth muscle present in the wall of the urinary bladder is detrusor muscle. It helps in contraction of the urinary bladder during micturition.
So, the correct answer is 'Detrusor'.

Which of the following is true for Neurilemma?

  1. Discontinuous at nodes of Ranvier

  2. Continuous at nodes of Ranvier and made by schwann cells

  3. Discontinuous at nodes of Ranvier and made by schwann cells

  4. Continuous at nodes of Ranvier and made by oligodendrocytes


Correct Option: B