Question

Question 10 Describe the various types of placentations found in flowering plants.

Class XI Biology Chapter - Morphology of Flowering Plants Page 83

Answer 1

hello there!!!

placentation :-

the arrangement of the ovules within the ovary is known as placentation.

placentation are of different types:-
1) Marginal
2) Axile
3) parietal
4) free central
5) basal

Marginal placentation :-

In this, the placenta forms a ridge along the ventral suture of the ovary and ovules are borne on the ridge.
e.g --> pea


Axile placentation :-

In this , the placenta is Axile and ovules are attached to it .
e g- China rose , tomato , lemon


Parietal placentation :-

in this , the ovules develop on inner wall of the ovary or on peripheral part.
e.g -> mustard , Argemone

Free central placentation :-

In this , the ovules are borne on central axis and septa are absent.
e.g-> Dianthus and Primrose.


basal placentation :-

in this , placenta develop at base of ovary & single ovule is attached to it.

e g -> sunflower , marigold.



hope it helps ⭐⭐⭐⭐

bebrainly2 ⭐⭐⭐⭐

Answer 2

Answer

Placentation refers to the arrangement of ovules inside the ovary. It is of five basic types.

(A) 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

(B) Parietal placentation

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

Parietal placentation

C) Axile placentation

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

Axile placentation

(D) 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

(E) 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 inDianthus and primrose.