Definition of pollen tube in English:
A hollow tube which develops from a pollen grain when deposited on the stigma of a flower. It penetrates the style and conveys the male gametes to the ovule.
- Guidance of the pollen tube down the style involves mechanical, chemical and physical cues that are not yet fully understood.
- In pre-zygotic mechanisms, the pollen tube may grow as far as the ovule but not penetrate it, or penetration may be achieved without fertilization.
- The grain is empty because the body cell and prothallial nuclei have moved out along the pollen tube towards the archegonia.
Definition of pollen tube in:
- US English dictionary