PLACENTATION

What is placentation? This is the arrangement of the ovules in an ovary.

Marginal placentation:

The placenta appears as one ridge on the ovary wall e.g. bean.

Parietal placentation:

• The placenta is on the ridges on ovary wall.
• Ovules are in them e.g. pawpaw.

Axile placentation:

• The placenta is in the centre.
• Ovary is divided into a number of loculi. e.g. orange.

 

Basal placentation.

• The placenta is formed at the base of the ovary e.g. sunflower.

 

Free Central placentation.

• Placenta is in the centre of the ovary.
• There are no loculi e.g. in primrose.

See also

POLLINATION

SEXUAL REPRODUCTION IN PLANTS

ASEXUAL REPRODUCTION

REPRODUCTION IN PLANTS AND ANIMALS

BIOLOGY PRACTICAL ACTIVITIES