Question

Apolysis is
a. Removal of mature proglottids
b. Removal of immature proglottids
c. Removal of gravid segments
d. None of the above

Answer 1

Hint: Apolysis separates cuticle from the epidermis, it is seen in the arthropods and similar organisms. It helps to maintain the length of the organism. It can be commonly observed in Taenia Solium.

Complete answer:
The word apolysis is derived from an ancient work which means discharge. Apolysis is the process when the cuticle separates from the epidermis. It is seen in arthropods. This cuticle provides skeletal support to the body. It is not elastic in nature. This cuticle sheds during the growth of the arthropod which leads to formation of a new large covering.

The arthropod goes into a dormant stage for a short period. The organism secretes enzymes which help in digestion of the cuticle from the inside. This causes the animal to detach from the cuticle as a whole. Hence the newly formed cuticle is on the inside which does not have any interference from the external environment. This forms the outer structure of the organism.

It is seen in Taenia Solium. The gravid proglottids detach from the posterior side of the strobila and is eliminated with the faecal matter of the host. This shedding is known as gravid proglottids. This regulates the length of the organism.

Hence, the correct answer is option (C).

Note: Apolysis is when the outer cuticle of the arthropod separates from the epidermis. This cuticle supports the skeletal portion of the body. This shedding replaces the cuticle with a new cuticle which is on the inside and does not interfere with the external environment in any way.