The plant body is made up of cells.cells are organized to form tissues,tissue system and organs in a
Study of the internal strctural organization of plant organs is known as plant anatomy.
Two groups of the angiosperms i.e.Dicot and monocot show different anatomical composition.
Tissue : Tissue is a group of cells having a comman origin, which are grouped together to perform
Plant body shows presence of variety of tissues.They are classified as follows.
[A] 1)Apical simple complex
3)Lateral (A)parenchyma (B)collenchyma (C)sclerenchyma
(a) special functional
types elements types elements
a)primary xylem a)tracheids a)primary a)sieve cells
(protoxylem) b)trachaea b)secondary b)(i) sieve tube
b)secondary xylem c)parenchyma (ii)companion cells
(metaxylem) d)fibres c)parenchyma
- plant tissues are of two types (1)meristematic and (2)permanent
- meristematic tissues consists of actively dividing cells.
- Based on their location, they are of 3 types
1) Apical meristem
2) Intercalary meristem
- 3) Lateral meristem
- Apical meristem and Intercalary meristems,as they appear early in the life of plant and contribute
to the formation of primary plant body,they are considered primary meristem.
- Secondary meristematic tissue : the meristems that occurs in the mature regions of shoots and
roots of many plants and apper later than primary meristem is called secondary or lateral mer-
- cells of permanent do not possess the property of cell division and these tissues are structurally
and functionally specialized.
- permanent tissues are of two types
(a)simple and (b)complex (conductive)
- simple permanent tissues consists of similar types of cells.
- They are divided into 3 types.
(a) parenchyma (b)collenchyma (c)sclerenchyma
- While complex tissues is a group of more than one type of cells ,working together as a unit to
perform definite functions.
- they are of two types.
(a)Xylem and (b)phloem
- Xylem is concerned with transportation of water and minerals.
- Phloem transports nutritive substance.
Anatomy of plant organs :-
- Three types of tissues systems are found in plant organs like root,stem and leaf.
(a) Epidermal tissue system
(b) Ground tissue system
(c) Vascular tissue system
- In most of the dicatyledons,after completion of the primary growth, further increase in
girth(diameter)takes place due to formation of secondary tissues.The length wise growth of
organs is due to apical meristem.
- the secondary growth involves lateral meristems like vascular cambiun work cambium.