Describe the various types of placentations found in flowering plants. | NCERT solution | Class 12 Biology | Unit-5 Morphology of Flowering Plants Biology

Q.:- Describe the various types of placentations found in flowering plants.

 

Answer
Placentation: The arrangement of ovules within the ovary is known as placentation. The placentation are of different types namely, marginal, axile, parietal, basal, central and free central.

The various types of placentations found in flowering plants are:

→ Marginal placentation: The ovary in which the placenta forms a ridge along the ventral suture of the ovary and the ovules develop on two separate rows is known to have marginal placentation. This type of placentation is found in peas.

marginal-placentation

→ Parietal placentation: When the ovules develop on the inner walls of the ovary, the ovary is said to have parietal placentation.

parietal-placentation

→ Axile placentation: In axile placentation, the placenta is axial and ovules are attached to it. Examples include China rose, lemon, and tomato.

axile-placentation

→ Basal placentation: The ovary in which the placenta develops from its base and a single ovule is found attached to the base is said to have basal placentation. It is found in marigold and sunflower.

basal-placentation

→ Free central placentation: In free central placentation, the ovules develop on the central axis while the septa are absent. This type of placentation is found in Dianthus and primrose.

free-central-placentation