Question

Which layer of the pollen grain grows out through the germ pore to form the pollen tube?

Options

• The intine (inner wall composed of cellulose and pectin)

• The exine (outer wall)

• The generative cell membrane

• The pollen coat or pellicle

Answer 1

The intine is the inner wall of the pollen grain composed of cellulose and pectin. During hydration and germination of compatible pollen, the intine grows out through the germ pore to form the pollen tube. The exine (outer wall) remains behind.