Question

a) Endosperm development in most of the plants is nuclear type
b) In rice, endosperm is starchy and present in mature seed.
A. Both (a) and (b) are correct
B. Only (a) is correct
C. Only (b) is correct
D. Both (a) and (b) are incorrect

Answer 1

The endosperm is a tissue produced inside the seeds of most of the flowering plants following fertilization. The endosperm is the source of nutrition in the animal diet. Cereal crops are grown for their edible fruit, which is primarily endosperm.

Step by step answer: The endosperm is triploid (that means three chromosome sets per nucleus) in most of the species. It surrounds the embryo and provides nutrition in the form of starch, though it can also contain oils and proteins. For example, the wheat endosperm is ground into flour for bread (the rest of the grain is included as well in whole wheat flour), while barley endosperm is the main source of sugars for beer production. Other examples of endosperm that forms the bulk of the edible portion are coconut “meat” and coconut water and corn. Some plants, such as orchids, lack endosperm in their seeds.
There are three types of endosperm development:
-Nuclear endosperm formation: here repeated free nuclear divisions take place; if a cell wall is formed it will form after free nuclear divisions. Coconut water is an example of this.
-Cellular endosperm formation: a cell wall formation is coincident with nuclear divisions. Coconut meat is the cellular endosperm.
-Helobial endosperm formation: here a cell wall is laid down between the first two nuclei, after which one half develops endosperm along with the cellular pattern and the other half along with the nuclear pattern. Monocots are helobial.
So, the correct option is D

Note: In some groups the endosperm persists to the mature seed stage as a storage tissue example grains of the family Poaceae and in others it is absorbed during embryo development example members of family Fabaceae. Some mature endosperm tissues store fats example castor beans and in others store mainly starches example grains such as wheat and corn. The processed grain has a lower quality of nutrition. Thus endosperm has an important role within the human diet worldwide.