Question

In malesAscaris, the anus is
A. Absent
B. Replaced by gonopore
C. Replaced by cloaca
D. None of the above

Answer 1

Hint: Ascaris parasites live in the intestine and their eggs are passed into the faeces (poop) of infected people. Gonopore is a genital pore present in insects. It is an opening through which sperms or eggs are released.

Complete solution:
Ascaris also known as roundworm, is the most common helminth (a group of parasitic worms). Their body is round and cylindrical and has pointed ends. Their body is made up of a structure called the cuticle. They respire via a process called diffusion. They are present in the intestines of humans. They secrete certain inhibitors to target the digestive enzymes secreted by their host’s system, which helps them to remain alive in the body. In male Ascaris, the anus is replaced by cloaca. Cloaca is the last part of the rectum located behind the opening of the ejaculatory duct. Male Ascaris are smaller than females. They have a curved tail with pre and post anal papillae, cloaca, and a pair of spicules that receives both faeces and sperms. From the cloaca, two equal chitinous spicules rise or penial setae project out. These are helpful in the process of copulation.

Note: Larvae of Ascaris hatch from ingested eggs and undergo pulmonary migration before developing into adult worms in the small intestines. Adult worms generally eat the food of their hosts, but heavy infections cause tangles of worms which can obstruct the gut. It affects humans causing a disease called ascariasis.