Question

Which surface of an epithelial cell lies closest to its blood supply

Answer 1

Answer: Basal surface is the surface of epithelial cell lies closest to its blood supply.

There are three surfaces in the epithelial cell.

1. apical

2. lateral

3. basal

1. Apical surface :  This is the surface which faces towards the cell and it is the exposed layer.

2. Lateral surface : This is the surface which is in between the adjacent cells.  

3. Basal surface :  It is divided into two lamina : Basal and Reticulate.

Basal lamina is made up of glycoproteins and collagen, this lamina remains separated from underlying connective tissue. Basal lamina is in attachment with Reticulate lamina.  Reticulate lamina is in contact with underlying connective tissues this arrangement forms a basal membrane for linking the epithelial surface with connective tissue layer or region of blood supply.

Answer 2

Answer: The surface of an epithelial cell which lies closest to its blood supply is called as the Basal surface.

Epithelial cell is primarily composed of two surface-

1) Apical surface- It is exposed to the environment and lies towards the lumen or internal organ cavity.  

2) Basal/ Basolateral surface- It is not exposed to the environment. It lies interiorly and attached to the basement membrane via integrin.

Epithelial cells do not have own blood supply. For obtaining nutrients, they are dependent on the blood capillaries which are present in the nearby tissues. For accomplishing this, the basal surface of epithelial cell plays an essential role. The nutrients from blood enters basal surface via basement membrane which is a selectively permeable membrane.

Thus, basal surface of epithelial cells lies closest to the blood supply.