76 ^|

A Handbook of Biology

Anatomy is the study of internal structure of plants and other organisms.

THË TÏSSÜËS



A tissue is a group of cells having common origin and common function.



Based on the capability of cell division, plant tissues are classified into 2

groups: Meristematic and Permanent.

MËRÏSTËMÅTÏÇ TÏSSÜËS (MËRÏSTËMS)



These are the tissues where active cell division and growth occurs. On

the basis of their origin, meristems are of two types.

(1) Primary Meristem (1° meristem) appear early in life of plant and

contribute in the formation of 1° plant body. :

Based on the position, 1° meristem is of 2 types:

Apical meristem^@

Intercalary

meristem.

@

a. Apical meristems

They occur at the tips of roots and shoots and produce primary tissues. It is

of 2 types:



Root apical meristem: It occupies the tip of a root.



Shoot apical meristem: It occupies the distant most region of the stem

axis. Some cells ‘left behind’ from shoot apical meristem, constitute the

axillary bud. (AIPMT 2002) They are present in the axils of leaves and are

capable of forming a branch or a flower.

Central cylinder

Cortex

Protoderm

Initials of central

cylinder

and cortex

Initials of

rootcap

Root cap

Root apical

meristem

(a)

(b)

Leaf primordium

Shoot apical

Meristematic zone

Axillary bud

Differentiating

vascular tissue

(a) Root apical meristem (b) Shoot apical meristem