Question

The product of triple fusion which acts as nutritive tissue for the development of embryo is
A. Zygote
B. Placenta
C. Scutellum
D. Endosperm

Answer 1

Hint: The process of triple fusion was discovered by Strasburger. Triple fusion involves both syngamy and double fertilization. It is a unique feature of angiosperms and it was discovered by Nawaschin.

Complete answer:
Zygote
The fertilization of one of the male gametes with the egg nucleus results in the formation of the zygote.
Placenta
It is the part of the ovary where the ovules attach.
Scutellum
In some monocotyledons like the grass family, the cotyledon is called scutellum.
Endosperm
In triple fusion, nuclei of both the male gametes are released in the embryo sac. One of these nuclei fuses with the egg nucleus resulting in the formation of a diploid zygote. This process is called syngamy.
The nucleus of other male gametes fuses with the two polar nuclei present in the central cell and this results in the formation of triploid primary endosperm nucleus.
Endosperm is a characteristic storage tissue that supplies nutrition to the developing embryo. The endosperm is of the following types in the plants:
Nuclear endosperm- In this, the primary endosperm nucleus divides and redivides to form a large number of nuclei.
Cellular endosperm- In this, wall formation occurs after every division of primary endosperm nucleus so that it is of cellular form from the beginning.
Helobial endosperm- In this, the first division of primary endosperm nucleus is followed by cytokinesis to produce two unequal sizes of cells.

Note: The post-fertilization changes in the plants include endospore formation, embryo formation, seed formation, and fruit formation. The endosperm development precedes the embryo development.