CLASS: IX NCERT (CBSE)
Tissues
SUMMARY
1) A group of cells, that are similar in structure and work together to achieve a particular function, forms a tissue.
2) Types of plant tissues include meristematic and permanent tissues.
3) Meristematic tissues are rapidly dividing tissues.
4) Apical meristem is present at the apical or growing tips of stems and roots.
5) Lateral meristem is present in the radial portion of the stem or root.
6) Intercalary meristem occurs at the base of the leaves or at the internodes. Old meristematic cells lose the capacity to divide and transform into permanent tissues.
7) Types of permanent tissues include parenchyma, collenchyma and sclerenchyma.
8) Parenchyma containing chloroplasts are called chlorenchyma. Parenchyma containing large air cavities are called aerenchyma.
9) Complex permanent tissues are made of more than one type of cells and are of 2 types-xylem and phloem.
10) Tracheids are tubular dead cells that transport water.Vessels are elongated dead cells that transport water and minerals.
11) Xylem parenchyma cells are living and they store food.
12) Xylem fibres are elongated dead cells with lignin that provide mechanical support.
13) Sieve tubes are elongated living cells that transport food from leaves to the stem and the roots.
14) Companion cells help in conduction of food to sieve tubes.
15) Phloem parenchyma store food.
16) Phloem fibre provide mechanical support.
17) Protective tissue protects the plants from the surroundings.
18) Epidermis is the outermost protective layer of roots, stems and leaves. Outermost layer in older roots and stems is called cork that contain dead cells. Epidermis is covered with a water proof layer called cuticle.
19) Types of Animal Tissues include epithelial tissue, connective tissue, muscular tissue and nervous tissue.
20) Epithelial tissues form a protective layer.
21) Different types of epithelial tissues are classified based on their shape and function.
22) Squamous epithelium are found in the organs to provide mechanical support.
23) Columnar epithelium are found in the lining of the organs to facilitate the movement of nutrients.
24) Glandular epithelium are found in the glands to produce secretions.
25) Ciliated epithelium are found in the lining of the respiratory tract.
26) Cuboidal epithelium are found in organs to provide mechanical support.
27) Stratified epithelium are found in places of wear and tear.
28) Connective tissue connects different organs. Different types of connective tissues are classified based on their shape and functions. Blood is a type of fluid connective tissue.
29) Bone is a hard porous tissue that protects the internal organs.
30) Fibrous connective tissue pack and bind various organs.
31) Ligaments connect two bones and tendons connect bones to the muscles.
32) Cartilage is found at the end of long bones to give flexibility.
33) Areolar connective tissue fills the space inside organs.
34) Adipose tissue is found below the skin and around kidneys.
35) Man can move because of the elasticity and flexibility of muscular tissues.
36) Striated muscles help us move our limbs at will.
37) Unstriated muscles are found in the iris of the eye and bronchi of the lungs.
38) The contraction and relaxation of cardiac muscles cause heart beats.
39) Nervous tissue transfer information from one part of the body to another. Nervous tissues have elongated cells called neurons. Neurons join end to end to form nerve fibres.
