Answers to Hands-on Pg 47-49

Aim : To observe the germination of pollen grains

Observation :

Pollen grain

Germinating pollen grain

Discussion

1. The slide with the sucrose solution.
2. To stain the male nuclei and the tube nuclei.
3. The surface of the pollen grain is coarse and has germinating pores.
4. The sucrose solution secreted by the stigma cells stimulates the growth of a pollen tube which grows into the ovule to fertilise the eg cell and polar nuclei in the embryo sac