A group of cells similar in structure, function, and origin is called tissue.
There are four types of tissues found in animals: epithelial tissue, connective tissue, muscle tissue, and nervous tissue.There are various functions carried out by tissues.
1. Epithelial tissue forms the covering or lining of most of the organs. The permeability of the epithelial tissue plays a great role in the exchange of materials among various organs it also plays an important role in osmoregulation.
2. Connective Tissue fills the gap between tissues and provides support, protection and facilitates movements.Also, helps in osmoregulation and temperature control.
3. Muscle cells are specialized cells which have the capability to contract and expand. Due to contraction and expansion, muscles facilitate various kinds of movements in the body.
4. Nervous tissue conducts impulses in response to various stimuli.