What Is PLANT TISSUE

Tissue, The group of cells which are similar in
structure and works together to get a particular
function is called tissue and the group of tissue
forms a organ.
Plant tissue- Plants have a large number
of supportive tissue . But Because the
plants does not show locomotion. They
requires less energy so the supportive
tissue they contain is bassically dead.
There are two types of plant tissue-
1.) Meristematic tissue
2.) Permanent tissue
1.) Meristematic tissue- The meristematic tissue
is generally known as dividing tissue. The cells
of this tissue are very active. This cells contain
dense cytoplasm they have thin cellulose
walls and also have prominent nuclei.They
lack vacuoles.
Meristematic tissue is of three types –
i) Apical meristem- It is present at the
growing tips of roots and stem and
increases the length of the stem and the
root.
ii) Cambium- The girth of the stem or root
increases due to cambium.
iii) Intercalary meristem- It is sees in some
plants located near the node.
2.) Permanent tissue- When the meristematic
lose the ability to divide it converts into
permanent tissue.
Permanent tissue is of two types-
i) Simple permanent tissue – A few layers of
cells beneath the epidermis is bassiclly
known as simple permanent tissue.The
most common simple permanent tissue is
parenchyma. A) The parenchyma contains
unspecialised cells with thin cell walls and
mostly cells are living cells. This cells are
loosely arranged because of this large
spaces are found in this tissue. This tissue
basically stores food. In some conditions
it contains chlorophyll and it hence
performs photosynthesis than it is known
as chlorenchyma and in aquatic plants
large air cavities are present in
parenchyma this type of parenchya tissue
is known as aerenchyma.
b) Collenchyma – The flexibility of plants is
due to collenchya. Due to this the plants
can bend from various part like tendrils and
stems. This tissue also provides mechanical
support to the plant. This tissue can be
found in leafs stalks below the epidermis.
This tissue contains living cells and at the
corners this are elongated and are
irregularly thickened. This does not have
large spaces between them they have very
small spaces between them.
c) Sclerenchyma - This tissue is responsible
for the hardness and stiffness of plant. An
ex is the husk of coconut it is made up of
sclerenchymatous tissue. This tissue
generally contains dead cells and they are
long and narrow as the walls are thickened
due to lignin. The cells does not have any
space.
ii) Complex permanenet tissue- The complex
tissue is made up of more than one type of
cells. All these cells coordinate to perform a
common function. The examples of the
complex tissue is xylem and phloem.These
both tissue are conducting tissues.
a) Xylem- It consists of tracheids, vessels,
xylem parenchyma and xylem fibres. In this
trachieds and vessels have thick walls and
many are dead cells when they mature.
Trachieds and vessels are tubular
structures. This feature allow them to
transport water and minerals vertically. The
parenchyma stores food. Xylem fibres are
mainly suppotive in functions.
b) Phloem- This tissue is made up of five
types of cells sieve cells, sieve tubes,
companion cells phloem fibres, phloem
parenchyma. In this sieve tubes are tubular
cells with perforated walls. Phloem
transports food from leaves to other parts
of the plant. Except phloem fibres, other
x
phloem cells are living cells.