Question

What are the four types of epithelium based on their special functions ?

Answer 1

Epithelium:

1. The epithelium cells are variously modified in structure to carry out different types of functions.

Classification based on the Specific Functions

Based on the specific functions, the epithelial tissues are classified into four types.

Sensory epithelium :

1. Sensory epithelium possesses sensory hairs on its free surface.
2. These cells help to detect external stimuli with the help of their hair.
3. The sensory epithelium is found in taste buds for detecting the taste sensation.
4. It is found in the nasal epithelium for detecting the sense of smell.

Germinal epithelium :

1. The germinal epithelium consists of cuboidal cells.
2. It occurs in gonads and helps in the formation of gametes.

Ciliated epithelium :

1. It may be columnar or cuboidal epithelium in which the cells possess cilia on their free surface.
2. It occurs in sperm ducts, uriniferous tubules, the lining of the respiratory tract, and oviducts.
3. The cilia help to push the ovum in the oviduct from the fallopian duct towards the uterus.
4. It helps to push the dust particles out of the respiratory tract.

Glandular epithelium :

1. In some regions, part of the epithelial tissue folds inward to form a multicellular gland.
2. The cells of these glands are called gland cells and can secrete substances.
3. The epithelium is called the glandular epithelium.