Question

Observe the example given in the box and find out how many of them possess a single ovule in each ovary?
Papaya, watermelon, wheat, paddy, orchids, and mango.
(a)Three
(b)Four
(c)Five
(d)Six

Answer 1

Hint: Plants that have a single ovule in the ovary are usually pollinated by the wind which is known as anemophily. The flowers of such plants are packed into an inflorescence and lightweight pollen is produced in large numbers to increase the chances of pollination.

Complete Answer:
Out of the given plants, the ones that possess a single ovule in each ovary are paddy, mango, and wheat. The other plants which are papaya, watermelon, and orchids have multiple ovules present in each ovary. After fertilization, ovules become seeds and the ovary becomes the fruit. Hence, we can see that plants like mango and wheat have only one seed in their fruit thus indicating that there was only one ovule in the ovary whereas plants like papaya and watermelon have multiple seeds in their fruits thus indicating that there were multiple ovules in the ovary.

Additional information:
The arrangement of ovules inside the ovary is known as placentation and it is of the following types:
Marginal: The ovules are arranged along a ridge along the ventral suture of the ovary in two rows and it is seen in pea.
Axile: The ovules are present in a multilocular ovary and it is seen in china rose, tomato, and lemon.
Parietal: The ovules are borne on the periphery of the ovary wall and it is seen in mustard and argemone.
Free-central: The ovules are borne on the central axis and no septa are present. It is seen in Dianthus and Primrose.
Basal: A single ovule is attached to the base of the ovary and it is seen in sunflower and marigold.

So, the correct option is ‘Three’.

Note:
-Ovary in parietal placentation is one-chambered but it becomes two-chambered due to the formation of a false septum.
-Ovary is the enlarged basal part of the carpel in which ovules are present.
-The carpel also consists of a stigma that receives the pollen grain and style which is a long hollow tube that allows the pollen tube to germinate.