Question

Excretory pore of Ascaris occurs

• A. At posterior end
• B. In the middle of body
• C. Behind the mouth
• D. Near the posterior end

Answer 1

The correct option is C Behind the mouth

One pair of excretory canals lie on the lateral lines. The epidermis is thickened at the site of the lateral lines and bears a canal. Each canal consists of one single cell with a hollow cavity. A cross-connection runs between the lateral canals. An excretory pore lies mid-ventrally just back of the mouth. Rossett cells (one per each canal) are associated with each tube in other species of nematodes.

So, the correct answer is 'Behind the mouth'.