TISSUE
Epithetical Tissue
(i) On the basis of cell layers
(a) When an epithelium has a single layer of cells it is called a simple epithelium.
(b) Where as a multiple tier of cells are known as stratified epithelium.
(ii) On the basis of simple shape of cells:
Ø  Cuboidal : its occurrence is in kidney tubules, salivery glands, inner lining of the cheek. Its main function is to give mechanical strength.
Ø  Columnar : its occurrence is in sweat gland, tear gland, salivary gland its main function is to gives mechanical strength concerned with secretions.
Ø  Squamous : when it forms a living as that of blood vessels, it is called endothelium.
Its main function is to protect the underlying parts from injury, entry of germs, etc.
Ø  Connective tissue : Its main function is to bind and support other tissues.
There are a few types of connective tissue.

Connective Tissue
Arelor
(i) Tendon
(ii) Ligament

Adipose Skeletal
(i) Bone
(ii) Cartilage

Fluid
(i) Blood
(ii) Lymph

A. Areolar tissue : It fills spaces inside organs found around muscles, blood vessels and nerves. Its main function is to joins skin to muscles, support internal organs, help in the repair of tissues. Whereas tendon’s main function is to connect muscles to bones and ligament is connects bones to each other.

B. Adipose tissue : Its occurrence is below skin, between internal organs and in the yellow bone Marrow. Its main function is to storage of fat and to conserve heat.

C. Skeletal tissue : Bone & cartilage occurrences is in nose, epigotis and in intervertebral disc of mammals. Its main function is to provide support and flexibility to body part. Whereas bone protects internal delicate organs provides attachments for muscles, bone marrow makes blood cells.

D. Fluid tissue : Blood & Lymph blood transport O2 nutrients, hormones to tissues and organs. Whereas leucocytes fight diseases and platelets help in cloting of blood. Lymph transport nutrients into the heart and it also forms the defense system of the body.

Muscular Tissue
It is specialized for ability to contract muscle cells.
Types of Muscular tissue:
A. Skeletal muscle: It attached primarily to bones. Its main function is to provide the force for locomotion and all other voluntary movements of the body.
B. Cardiac muscle: It occurs only in the heart. The contraction and relaxation of the heart muscles help to pump the blood and distribute it to the various parts of the body.
C. Smooth muscle: It can be found in stomach, intestines, and blood vessels these muscles cause slow and prolonged contractions which are involuntary.
D. Nervous tissue: This tissue is specialized with a capability to conduct electrical impulses and convey
information from one area of the body to another. Most of the nervous tissue (98%) is located in the central nervous system. The brain and spinal cord.
Types of Nervous Tissue
Ø  neurons
Ø  neuroglia

Important facts regarding animal tissue:-
Ø  Muscles contain special protein called contractile protein. Which contract and relax to cause
Ø  Fat storing adipose tissue is found below the skin and between internal organs.
Ø  Two bones are connected to each other by a tissue called ligament. This tissue is very elastic.
Ø  The skin, the living of the mouth, the living blood vessels, kidney tubules are all made up of epithelial tissue.
Ø  Voluntary muscles and cardiac muscles are richly supplied with blood whereas involuntary muscles are poorly supplied with blood.