Question

Our outer layer of skin is an example of which type of tissue?
(a) Muscular
(b) Epithelial
(c) Connectives
(d) Nervous

Answer 1

Hint: These are thin tissues that cover all the exposed surfaces of the body. The blood vessels and nerves are not found in these tissues.

Complete answer:
The epithelial tissues constitute our outer layer of skin. They constitute the external skin, the inner lining of the mouth, alimentary canal, secretory glands, the liner of hollow parts of each organ like the guts, lungs, eyes, ears, the urogenital tract, and also the ventricular system of the brain and central canals of the spinal cord.
Cells of epithelial tissue are densely packed together with a minimal amount of intercellular substance and are firmly attached by intercellular junctions. Their cells rest on a basement membrane partly derived from underlying connective tissue.
The function of Epithelial Tissue:
Functions of epithelial cells include secretion, selective absorption, protection includes protection against abrasion, radiation damage, chemical stress, and invasion by pathogens. These tissues also help in transcellular transport and sensing. As we all know that the epithelial layers don't contain any blood vessels, in order that they must receive nourishment via diffusion of drugs from the underlying animal tissue, through the basement membrane
Types of Epithelial Tissue:
- Based on layers of cells, the epithelial tissue is of two types: Simple epithelial tissue and stratified epithelial tissue.
- When the epithelial tissue is composed of a single layer of cells, it is called simple epithelial tissue and when the epithelial tissue is composed of two or more layers of cells it is called stratified epithelial tissues.
- Based on the shape of the cells, the epithelial tissue is of three types:
- Squamous epithelial tissue: These consist of extremely thin cells that resemble the scales of a fish.
- Cuboidal epithelial tissue: These contain cells that appear square in cross- section but are marginally longer and are wide.
- Columnar epithelial tissue: This consists of elongated cells involved in the absorption of materials.
- So, altogether the number of cell layers and cell types together give rise to 6 different types of epithelial tissue these are namely:
Simple squamous epithelial.
Simple cuboidal epithelial.
Simple columnar epithelial.
Stratified squamous epithelial.
Stratified cuboidal epithelial.
Stratified columnar epithelial.
Hence, the correct answer is, ‘(b) Epithelial’.

Note:
- The epidermis consists of the outermost layers of cells within the skin.
- Cells of epithelial tissue are densely packed together with a minimal amount of intercellular substance.
- Epithelial layers don't contain any blood vessels.
- The epithelial cells include secretion, selective absorption, protection includes protection against abrasion, radiation damage, chemical stress.