Question

Basal placentation occurs in an ovary which is
A. Unilocular
B. Bilocular
C. Multilocular
D. Lateral

Answer 1

Hint: Ovary is the female reproductive part which has the female gametes called ovules. They fertilize with the pollen to form the embryo and thus the fruit. The placement of this fertilized ovule in the ovary makes a difference. The number of ovules fertilized is also important.

Complete answer:
Placentation occurs when the male and female gametes fuse to give zygote equivalent structure. This can take place at any place of the ovary. So when the placentation takes place at the base of the ovary and a single ovule is seen attached to it.
This is called unilocular and basal placentation. It is usually found in the family Compositae and Asteraceae.

> Option A: Unilocular: the ovary with one ovule shows the basal placentation. It happens in the angiosperms. It forms the largest group of the flowers having basal placentation. The part of the ovary where funiculus attaches is the placenta.

> Option B: Bilocular: the ovary with two ovules shows the parietal placentation.

> Option C: Multilocular: many ovules in the ovary implant on the axile so is called the axile implantation.

> Option D: Lateral: it is a feature of the superior unilocular ovary. It is also called marginal placentation.

Hence, the correct answer is option (A).

Note: Angiosperms usually have the basal placentation. Examples are sunflower and marigold. Placentation tells us about the placement of ovules in the ovary. This placenta will provide nourishment to the growing embryo. In the parietal placentation, the one chamber is divided into two chambers by the formation of a false septum thereby making the bilocular arrangement.