Types of stomata



Types of Stomata:


 On the basis of size, shape, number and and arrangement of Subsidiary cells stomata are classified into six types.

Metcalf and Chalk defferentiated various types of stomata.

A. Anamocytic:

Guard cells are surrounded by 4 or more subsidiary cells which are similar in size and shape. Two subsidiary cells are present in bothpolar regions of guard cells and the remaining two are present on two lateral sides.
Ex: Rananculaceae, Papaveraceae, Tridax procumbans.

B. Anisocytic:

Guard cells are surrounded by 3 subsidiary cells and are differ in size. Two subsidiary cells are bigger in size at lateral sides and one cell in smaller in size at one polar region of guard cells.
Ex: Cruciferae, Umbilliferae, Datura.

C. Paracytic:

Guard cells are surrounded by two large subsidiary cells which are similar in size and are present at the two lateral sides of the guard cells.
Ex: Rubiaceae, Magnoliaceae, Ixora.

D. Diacytic:

Guard cells are surrounded by two large subsidiary cells which are similar in size and are present at the two polar sides of the guard cells.
Ex: Caryophylliaceae, lamiaceae.

E. Actinocytic:

Guard cells are surrounded by elongated cells.

F. Cyclocytic:

Guard cells are surrounded by four or more subsidiary cells.

types of stomata



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