Question

state any four functions of epithelium​

Answer 1

Answer:

Functions of epithelial cells include secretion, selective absorption, protection, transcellular transport, and sensing. Epithelial layers contain no blood vessels, so they must receive nourishment via diffusion of substances from the underlying connective tissue, through the basement membrane.

Answer 2

In case of a glass slab, the incident ray is parallel to the emergent ray, that means the angle of incidence is equal to the angle of emergence. The explanation is as follows: When a ray of light is incident on the surface of the glass slab, it undergoes refraction.