Question
How does pollen tube enter the ovule?
✓
Answer
Pollen tube reaches the ovary through style and it shows chemotrophic growth. Entry of pollen tube into ovule occurs by one out of three ways :
(a) Porogamy, (b) Mesogamy, (c) Chalazogamy.
1. Porogamy : Pollen tube enters the ovule through micropyle. This is the most common type found in plants.
2. Mesogamy : Pollen tube enters the ovule by penetrating the integuments e.g. cucurbita popular.
3. Chalazogamy : Pollen tube enters the ovule through chalaza e.g. Casuriana, Betula.
(a) Porogamy, (b) Mesogamy, (c) Chalazogamy.
1. Porogamy : Pollen tube enters the ovule through micropyle. This is the most common type found in plants.
2. Mesogamy : Pollen tube enters the ovule by penetrating the integuments e.g. cucurbita popular.
3. Chalazogamy : Pollen tube enters the ovule through chalaza e.g. Casuriana, Betula.
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