The document summarizes the key differences between three types of plant tissues: parenchyma, collenchyma, and sclerenchyma. Parenchyma cells are living cells found in soft plant parts with thin, uniformly thick cell walls. Collenchyma cells are also living and found in young stems and petioles, with unevenly thickened cell walls. Sclerenchyma cells are dead with thick, lignified cell walls found in woody and hardened parts. The document also compares xylem and phloem tissues, noting that xylem transports water and minerals unidirectionally upward, while phloem transports sugars bidirectionally using sieve tubes and companion

1. Plant Tissue

3. Characteristics Parenchyma Collenchyma Sclerenchyma
Occurrence
These are living cells found in the
soft parts in the plant body.
They are living cells found in the
and in the parts of young stems.
They are dead cells present only in the
parts.
Cell wall They possess very thin cell walls
They have thick cell walls but it is
nature.
They have both thick and regular cell
Nature They are unspecialized in nature. These cells are specialized cells. These are also specialized cells.
Intercellular space Space is present between the cells. They have only little intercellular
They do not have any intercellular
hard in nature.
Functions
They undergo photosynthesis, store
food and are also useful in the
exchange.
Does not undergo photosynthesis but
flexibility and mechanical support to
against the wind or etc.
Gives mechanical strength to the
useful in the transportation of food
through xylem and phloem.
Made of It is made up of cellulose. It is made up of cellulose and pectin. It is made up of lignin.

4. Elements of comparison Parenchyma Collenchyma Sclerenchyma
Description
They are thin-walled cells that make up the
inside of non-woody plant structures including
stems, roots and leaves.
They are plant tissues that consist of living
elongated cells with unevenly thickened walls
and acts as support especially in areas of
primary growth.
Is a supportive or protective tissue in higher
plants (vascular plants) composed of cells with
walls thickened and often lignified.
Cell wall Thickness
Made up of cells having very thin cell wall that
is uniformly thickened.
Made up of unevenly thickened cell wall. Made up of a thick and rigid cell wall.
Presence
Cells are found in every soft part of the plant
like leaves, fruits, bark, flowers, pulp and pith
of the stems.
Cells are found in petiole, leaves and young
stems, appearing as a continuous ring beneath
the epidermis.
Cells are found in the mature parts of the plant
like herbaceous perennials and woody plants.
Cell Shape
Usually isodiametric in shape, however they
can still have other various shapes.
Cells are usually polygonal in shape. Cells are tubular in shape.
Cells They are unspecialized cells. They are specialized cells. They are specialized cells.
Cell wall components Cell wall is made up of cellulose.
Cell wall is made up of pectin and
hemicelluloses.
Cell wall is made up of waterproofing lignin.
Intercellular Spaces Cells are loosely packed. Cells have little space between cells.
Cells have no intercellular spaces present
between them, cells are tightly packed.
Cell Constituents Consists of living cells at maturity. Consists of living cells at maturity.
Consists of dead cells at maturity and thus why
protoplast is absent.
Composition Found abundantly in plant tissues.
Collenchymacells make up the epidermal
layers.
Found in plenty on the outer woody stem
portion of large trees.
Cells Origin
Cells originate from protoderm and ground
meristem.
Cells originate from pro-cambium like cells in
the ground meristem.
Cells originate from protoderm pro-cambium
and ground meristem.
Function
Roles include gaseous exchange, storage of
food and photosynthesis.
Providing mechanical support and elasticity to
the plant.
Provide mechanical support and
transportation of water and nutrients to the
plants.
Pit Fields Cells have primary pit fields on the cell wall. Cells have no pit fields on the cell wall. Cells have simple and bordered pit fields.
Cell Wall
The cell walls are primarily in nature without
sculpturing.
The cell walls are primarily in nature with no
sculpturing.
Cell walls are formed secondarily with various
sculpturing like annular, spiral and reticulate
etc.

5. S.No.
Parenchyma
Collenchyma Sclerenchyma
1 They are plant’s simple tissue cells . They are plant’s simple tissue cells. They are plant’s simple tissue cells.
2 They are living cells. They are living cells. They are dead cells.
3 The cells of parenchyma have thin walls Cells of collenchyma have slightly thick walls.
Sclerenchyma tissue cells have thick cell
walls.
4 Cells of parenchyma are uniformly thin. Cells of collenchyma elongated. Cells are long and narrow.
5 The cells are loosely packed.
Cells of these tissues are irregularly thickened
at the corners.
The cell walls of Sclerenchyma
are thickened due to Lignin.
6
The cells of parenchyma have large
intercellular spaces.
The cells of collenchyma have very little
intercellular spaces.
The cells of sclerenchyma have no internal
space inside the cells.

10. Xylem Phloem
Definition
Xylem tissues are the tubular-shaped structure, with the absence of cross walls. This tissue resembles
the shape of a star.
Phloem tissues are tubular-shaped, elongated, structures with the presence of walls with thin sieve
tubes.
Location
It is located in the centre of the vascular bundle. It is located on the outer side of the vascular bundle.
Fibres
Xylem fibres are smaller. Phloem fibres are larger.
Found In
They are present in roots, stems and leaves. They are present in stems and leaves, which later transports and grow in roots, fruits and seeds.
Movements
These tissues move in a Unidirectional. (only in one direction – upward direction) These tissues move in a Bidirectional. (both ways – up and down)
Comprises
They live with hollow dead cells. They live with cytoplasm without the nucleus.
No of Tissues
The total amount of xylem tissue is more. The total amount of phloem tissue is less.
Features
It consists of tracheids, vessel elements, xylem parenchyma, xylem sclerenchyma and xylem fibres.
It consists of four elements: companion cells, sieve tubes, bast fibres, phloem fibres, intermediary cells
and the phloem parenchyma.
Functions
Transports soluble mineral nutrients and water molecules from the roots to the aerial parts of the
plant.
Transports food and other nutrients including sugar and amino acids from leaves to storage organs
and growing parts of the plant.
Vascular Bundles
Forms vascular bundles with phloem. Forms vascular bundles with xylem.
Functions
Provides mechanical strength to the plant and helps in strengthening the stem.
Translocates the synthesized sugars by the photosynthetic areas of plants to storage organs like roots,
bulbs and tubers.
Functions
It is responsible for replacing the total amount of lost water molecules through transpiration and
photosynthesis.
It is responsible for transporting proteins and mRNAs throughout the plant.