Question

PEN stands for
A) Primary endosperm nourishment
B) Primary endosperm nucleus
C) Primary embryo nourishment
D) Poly embryo nourishment

Answer 1

Hint: PEN created in the process of double fertilization in the angiosperms (flowering plants). This cell later develops into the endosperm, which is the main source of nutrition for growing embryos.

Complete answer:
Primary Endosperm Nucleus:-
>Pen stands for Primary Endosperm Nucleus.
>Primary Endosperm Nucleus form during the event of double fertilization in angiosperms.
>Primary Endosperm nucleus is the one that is formed by the fusion of two polar nuclei in the embryo sac of seed by the haploid sperms.
>The sperm that fuse with polar nuclei is the second sperm, first sperm fuses with the egg cell or ovum to form Zygote.
> This fusion results in a triploid (3n) nucleus.
> Primary Endosperm Nucleus divides to form the endosperm tissue.
> It is the main source of nutrition for the embryo in angiosperms.
>Therefore, we have seen that PEN stands for Primary Endosperm Nucleus.
Hence, option A is the right answer.
Note: Remember to keep in mind that the function of endosperm is to provide nutrition to growing embryos inside the seed. In some types of seeds it is completely consumed by the growing embryo but in some seeds it is not completely consumed by the growing embryo.