2. PLANT
GROWTH
• Plants can grow through out their
lives.
• Plant grows due to the rapid division
and differentiation of certain
specialised cells.
• These specialised cells are called
MERISTEM
3. MERISTEM
• Meristem is a Greek word Meristosis meaning to divide.
• Meristem is a type of tissue that occurs in plants.
• It consists of undifferentiated cells called meristematic
cells which are capable of cell division.
• Meristem is a region of plant tissue found chiefly at the
growing tips of roots and shoots which actively divide to
give rise to new cells.
• A meristematic tissue consists of a group of cells which
remain in a continues state of division or they retain their
power of division.
4. Characteristics Of Meristem
• Composed of immature cells which are at the
state of division and growth.
• Intercellular spaces are absent.
• Cells are rounded, oval or polygonal in shape.
• Cells are always living and thin walled.
• Each cell has abundant cytoplasm.
• These cells are capable of regular, continuous
mitotic division.
5. Classification Of Meristem
• Meristem can be classified mainly based on its
stage of development, based on its orgin and
based on its position in plant body.
• Based on the position in the plant body, Meristem
are:-
• Apical Meristem
• Intercalary Meristem
• Lateral Meristem
6.
7. Different Kinds Of
Meristems
TYPE LOCATION FUNCTION
APICAL Tip of stem and root Increases the length of stem and
root
INTERCALARY Intermodal region Increases the length of stem
LATERAL Lateral surface. ie. At sides of stem
and root
Increases the girth of stem and root
8. APICAL MERISTEM
• Apical Meristem is the meristem present at the tip of root and stem,
commonly called as root apex and shoot apex respectively.
• Such meristems constitute the actively growing regions in the plant
body.
• Due to the activity of apical meristem the plant body keeps increasing
its length.
• Increase in the length of both root and shoot occurs.
9.
10. INTERCALARY MERISTEM
• Intercalary meristems are those meristems that
occurs at the base of the leaves.
• It is particularly common at the nodal regions; at the
base of leavesand at the base of internodes.
• It is responsible for the formation of branches at the
nodal regions.
• These type of meristem typically helps to increase
the length of the stem.
11.
12. LATERAL MERISTEM
• Lateral Meristem is the type of meristem
that lies on the sides of the plant body.
• It increases the diameter of plants.
• It provides strength to the plants for its
suitable growth.
13. Apical vs Intercalary vs Lateral
Meristem
APICAL MERISTEM INTERCALARY MERISTEM LATERAL MERISTEM
The area of actively dividing cells
that locates at the tips of the roots
and the shoots.
The area of actively dividing cells
which is located at the internodes.
The area of actively dividing cells
that is located at the lateral side of
the stem and the root.
Found at tips of root and shoot Seen at internodes or at the base
of the leaves.
Found at the lateral surface of the
stem and root.
Aids increase of height of the
plant by facilitating the growth of
the shoot and the root.
Contributes to the increase in
height with the growth of the
internodes.
Increases the thickness of the
plant by increasing the diameter of
the plant.
