What is Endosperm? Types, Formation & Functions – NEET & Class 12 Notes

Endosperm is the nutritive tissue that provides food to the developing embryo in angiosperms. It is formed as a result of triple fusion during double fertilization.

What is Endosperm?

Endosperm is a triploid (3n) tissue formed by the fusion of one male gamete with the two polar nuclei in the central cell of the embryo sac.

Formation of Endosperm

• One male gamete + Two polar nuclei → Primary Endosperm Nucleus (PEN) – 3n
• PEN undergoes repeated divisions to form endosperm

Types of Endosperm

Type	Example	Feature
Nuclear Endosperm	Coconut (liquid endosperm)	Free nuclear divisions first
Cellular Endosperm	Datura, Petunia	Cell wall formation after each division
Helobial Endosperm	Monocots	Intermediate type

Functions of Endosperm

• Provides nutrition to the developing embryo
• Stores food materials (starch, proteins, oils)
• In some seeds (like cereals), it remains persistent and forms the edible part

NEET Important Points

• Endosperm is usually triploid (3n).
• In coconut, liquid endosperm is nuclear type and solid endosperm is cellular.
• Endosperm development precedes embryo development.

This is a high-scoring topic in NEET – revise it carefully!