Epithelial Tissue
I. Simple Epithelium
Simple epithelium consists of a single layer of cells that rests on a membrane.
It primarily functions in absorption, secretion, filtration, and diffusion.
Because of its thinness, it does not provide much protection.
Types of Simple Epithelium:
1. Simple Squamous Epithelium
This type has flat cells with centrally located, flattened nuclei.
It is found lining areas where diffusion or filtration occurs-
alveoli of the lungs, blood vessels
2. Simple Cuboidal Epithelium
The cells are cube-shaped with centrally placed round nuclei
This epithelium is located in thyroid follicles, and the ducts of small
glands. It performs both absorption and secretion.
3. Simple Columnar Epithelium
These cells are tall and rectangular with nuclei located at the base.
Found lining the stomach, intestines, this epithelium plays a major role
in absorption and secretion.
Ciliated Simple Columnar Epithelium
Similar to simple columnar but with cilia on the top. It is found in the
uterine tubes and parts of the respiratory tract, where cilia help move
substances like mucus or ova.
, 4. Pseudostratified Columnar Epithelium
Though all cells rest on the basement membrane, the nuclei lie at
different heights. This gives a false appearance of having different levels.
This type often has cilia and goblet cells and is located in the trachea and
large bronchi, where it helps in mucus secretion and transport.
I. Simple Epithelium
Simple epithelium consists of a single layer of cells that rests on a membrane.
It primarily functions in absorption, secretion, filtration, and diffusion.
Because of its thinness, it does not provide much protection.
Types of Simple Epithelium:
1. Simple Squamous Epithelium
This type has flat cells with centrally located, flattened nuclei.
It is found lining areas where diffusion or filtration occurs-
alveoli of the lungs, blood vessels
2. Simple Cuboidal Epithelium
The cells are cube-shaped with centrally placed round nuclei
This epithelium is located in thyroid follicles, and the ducts of small
glands. It performs both absorption and secretion.
3. Simple Columnar Epithelium
These cells are tall and rectangular with nuclei located at the base.
Found lining the stomach, intestines, this epithelium plays a major role
in absorption and secretion.
Ciliated Simple Columnar Epithelium
Similar to simple columnar but with cilia on the top. It is found in the
uterine tubes and parts of the respiratory tract, where cilia help move
substances like mucus or ova.
, 4. Pseudostratified Columnar Epithelium
Though all cells rest on the basement membrane, the nuclei lie at
different heights. This gives a false appearance of having different levels.
This type often has cilia and goblet cells and is located in the trachea and
large bronchi, where it helps in mucus secretion and transport.
