Question

Which one of the following correctly describes the location of some body parts in the earthworm Pheretima?

• A. Two pairs of accessory glands in 16${}^{th}$ - 18${}^{th}$ segments.
• B. Four pairs of spermathecae in 4${}^{th}$ - 7${}^{th}$ segments.
• C. One pair of ovaries attached at intersegmental septum of ${14}^{th}and{15}^{th}$ segments.
• D. Two pairs of testes in ${10}^{th}and{11}^{th}$ segments.

Answer 1

The correct option is D Two pairs of testes in ${10}^{th}and{11}^{th}$ segments.

The body of Pheretima is made of 100-120 segments.
On segment 17 and 19 is a pair of accessory glands which open to the exterior. So, option A is incorrect.
There are four pairs of small pear-shaped bilobed spermathecae. Paired spermathecae occur in Pheretima in the first and last segment. So, option B is incorrect.
A pair of small white ovaries lies in the 13${}^{th}$ segment on either side of the ventral nerve cord. So, option C is incorrect.
There are two pairs of whitish testes in segments 10 and 11 which are enclosed in thin-walled coelomic spaces called testis sacs.
Thus, the correct answer is the option, D.