Question

Ruminate endosperm occurs in-
A. Cruciferae
B. Euphorbiaceae
C. Asteraceae
D. Annonaceae

Answer 1

Hint: The family is commonly known as the 'custard apple' family or soursop family. The seed of some of the members of this family consists of toxins.

Complete answer:
Ruminate endosperm is the condition in which the endosperm is dissected by in-growths of the seed coat. Ruminate endosperm is formed when the seed coat intrudes inward into the young endosperm via meristematic growth. Ruminate endosperm is found in the 'Annonaceae family'. Some other examples of families with ruminate endosperm are Rubiaceae, Arecaceae, Aristolochiaceae, Palmaceae, and Myristicaceae. The testa of seed coat gets folded into the endosperm.

Additional Information:
- The endosperm is produced from the Primary Endosperm Nucleus in the flowering plants as a result of 'Triple Fusion' during fertilization. It is triploid (3n) in most species.
- It surrounds the embryo and provides nutrition to it in the form of carbohydrates. It is a rich source of oil and protein. This can make endosperm a source of nutrition in animal diet.
- Endosperm can be further classified into three types on the basis of mode of development-
> Nuclear endosperm- It is formed by the repetitive division of the primary endosperm nucleus without the formation of walls. It is seen in Cotton, Coconut, Acalypha, etc.
> Cellular endosperm- It involves the formation of the wall just after the first nuclear division of the primary endosperm nucleus. It is seen in Datura, Petunia, Drimys, etc.
> Helobial endosperm- This type of endosperm lies intermediate between the nuclear and the cellular endosperm. It is seen in monocots like Eremurus.

So, the correct answer is ‘Annonaceae’.

Note:
- The endosperm is present in all angiosperms except in a few angiosperm families like Orchidaceae, Trapaceae, and Podostemonaceae.
- Mosaic Endosperm: It is also called heterogenous endosperm. It comprises two or more types of cells. It is seen in the endosperm of Zea maize which consists of red and white patches.
- In Petunia and Tomato, the endosperm consists of both diploid and tripod tissues.