Structure Of Mature Pollen Grain Flashcards
What is the exine?
The thick outer wall of the pollen grain
What is the thick outer wall of the pollen grain called?
The exine
Describe the exine.
2
The exine often has a very distinctive pattern, which is specific to the type of plant
The exine is made up of a very durable material that allows it to survive for long periods of time
Describe the appearance of the exine.
The exine often has a very distinctive pattern, which is specific to the type of plant
What allows the exine to survive for very long periods of time?
The fact that exine is made up of very durable material
The exine is made of very durable material, what does this allow for?
This allows the exine to survive for long periods of time
What is the intine?
The intine is a thin, inner coat on a pollen grain
What is the thin, inner coat on a pollen grain called?
The intine
Why are pollen grains not called gametes?
3
As they do not join with other cells
i.e. they are not involved in fertilisation
They form the male sperm nuclei which are actually the gametes
What do the pollen grains form?
Male sperm nuclei (male gametes)
What happens to the anther when the pollen grains have matured?
(3)
The walls of the anther become dry and they shrivel
This results in the splitting (dehiscing) of the anther walls
The pollen grains are then exposed on the outside of the anther
What is the splitting of the anther walls also called?
The dehiscing of the anther
What causes the anther walls to split?
The anther becoming dry and shrivelled
