Tissues (1).pptx FOR CLASS 8 AND 9 FOR ICSE

Tissue PPT for class 8 and 9

1. TISSUES PLANT AND ANIMAL TISSUES

2. Meristematic Tissues Cells actively divide-adds new cells to plant- helps in growth. Cells are small , cuboid. Thin cell wall. Large nuclei ,vacuoles almost absent. No intercellular space. One matured these cells don’t divide. Transformed into Permanent tissues. Characteristics

3. Permanent Tissues Cells that has lost the ability to divide. Perform some specific function. May be living or non-living. Divided as: *Simple permanent tissues. -Protective -Supportive *Complex permanent tissues . -Conducting

4. Simple permanent tissues Protective Tissue Features Thick cell wall. Found on the surface of roots ,stems and leaves. Location: Epidermis of leaves with waxy coating. Cork cells in the barks of trees.

5. Supporting Tissues 1. Paranchyma Features Thin walled cells,oval,circular or polygonal . Single large vacuole. Provides support. Stores food in potatoes. Sometimes contain chloroplast- Chlorenchyma - photosynthesis. Location: Soft parts of plants -cortex and pith.

6. 2. Collenchyma Features Elongated cells. Cell wall thickened at the corners. Provides support. Location: -Leaf stalks -Below the epidermis of stems.

7. 3 . Sclerenchyma Features Long ,narrow cells . Dead/Non-living. Very thick walls-deposition of lignin. Location: -Stems and veins of leaves.

8. Cross section showing all the Simple Tissue

9. Complex Permenant Tissues (Conducting /Vascular tissues) 1. Xylem Elongated and thick walled cells. Tubular passages-structure. Conducts water and dissolved materials absorbed by roots to upward parts. Older xylem cells forms wood-no conduction. Forms annual rings—age of a tree.

10. Xylem tissue consists of: Tracheids * Elongated dead cells-large empty cavity - lined end to end. *Highly lignified cell walls-gives mechanical support . Xylem Vessels/Tracheae *Elongated cells-forms long tubes for conduction of water and minerals. *Cell walls are hard , thick and lignified. Xylem Parenchyma *Living parenchyma cells. *Support and storage .

11. Complex Permanent Tissues (Conducting /Vascular tissues) 2 . Phloem Elongated and thick walled cells. Tubular passages-structure. Conducts upwards and downwards the food manufactured in the leaves.

12. Phloem tissue consists of: Sieve tubes *Elongated cells- forms tubes-has transverse walls perforated- Sieve plates. *Transports food to storage organs esp . Companion cells *Living parenchyma cells-helps sieve tubes. Phloem Parenchyma *Parenchymatous-helps phloem-storage of starch , fat and other organic material. Phloem Fibres *Sclerenchyma cells- support.

13. Vascular bundles in a cross section of stem

14. Epithelial Tissue Characteristics Thin ,protective continuous sheet of cells. Flat , cuboidal or columnar in shape. No space between cells. Functions: *Protection and Sensory perception (Skin) *Absorption ,Secretion (Intestines) Location: *Covers the body *Lines the body cavities & internal organs including blood vessels.

15. Categories of Epithelial Tissue Squamous Epithelium Thin ,flat cells with prominent nuclei. Protects the underlying parts from mechanical injury ,germs, harmful chemicals and drying up. Location: *Lining of the -mouth -nasal cavities -blood vessels -lymph vessels.

16. Stratifies Epithelium Several layers of same /different epithelial cells. Found in skin and cornea. Cuboidal Epithelium It is a single layer thick and made of cube-shaped cells. Found lining parts of the body such as the kidney tubules and walls of the respiratory bronchioles, glands(salivary , pancreas)

17. Columnar Epithelium Tall ,cylindrical cells arranged vertically . Found in the inner lining of stomach and intestines. Two types: 1.Ciliated Columnar Epithelium *Has a thread like protoplasmic projection—cilia at the free end. * Cilia that keeps lashing and move the materials through the organs. *Inner lining of trachea, fallopian tube.

18. 2 .Glandular Epithelium *Large cells that secrete certain chemicals. -Lining of the stomach and intestine. *Sometimes these cells gets folded inward to form compact ,hollow or tubular glands. -Sweat glands - T ear glands -Liver

19. Connective Tissue Characteristics: Binds one tissue to another. Connects various organs , keeping them in proper position. Abundance of matrix. Cells are fewer in number. They are mostly fibres . Types: -Connective tissue proper -Supportive c onnective tissue -Fluid connective tissue

20. Categories of Connective Tissue Connective tissue proper Helps in packing and binding organs. Types: *Areolar tissue -Widely spread , seen beneath the epidermis of skin. -Elasticity of skin. *Adipose tissue -Specialized cells to store fat. -Padding under the skin , kidney , eye ball, etc. –Insulation and protection.

21. Fibrous connective tissue -Elongated cells- fibres-strong and bundled together by areolar tissue. -They form; *Tendons—connects Muscle to Bone *Ligaments—connects Bone to Bone Cartilage *Non porous tissue-thick matrix *Semitransparent-no nerves & blood vessels. * Found in the tips of the nose, pinna, trachea ,bronchial tubes ; between vertebrae and end of long bones. Bone tissue * Hard porous tissue-living cells—osteoblasts and rigid mass of organic matter. *Good supply of blood vessels & nerves. *Found in all bones. Supportive connective tissue

22. Fluid connective tissue Blood Always moving throughout the body. Has 2 parts: *Liquid part- Plasma *Cellular part- -Red Blood cells(Transportation) -White blood cells (Immunity) -Platelets (Blood clotting) Lymph Fluid surrounding body cells. Contains blood plasma along white blood cells. Transportation and immunity