Functions:

A) Stigma – Stigma is the terminal sticky part of the carpel and it functions to trap the pollen grains on its sticky surface.

B) Pollen tube - The pollen tube helps to transfer the male germ cells from the pollen grains to the female germ cells inside the ovary at the base of the flower.

C) Female germ cells – The female germ cells of a flower get fertilized by the male germ cells and develop into a zygote.