Question

The non-keratinized stratified squamous epithelium is present in
A) Epidermis of skin of hard and vertebrate
B) Vagina and cervix
C) Oral cavity
D) Vagina, cervix and oral cavity

Answer 1

The non-keratinised stratified squamous epithelium are the epithelial cells which lack keratin. These cells secrete mucus which acts as a protective and lubricating layer. These are found in the organs that need to be kept moist so as to prevent them from drying.

Complete answer:
To answer this question, we must know about the cells present in the different organs of our body.
i) Epidermis of skin- The epidermis is made up of keratinised stratified squamous epithelia. This epithelium is present in those organs which are in close contact with the environment. The keratin is a protein pigment present in the skin, horns which prevent the skin from the external environment.
ii) Vagina and cervix- Vagina and cervix are the respiratory organs of females. These are lined with non-keratinised squamous epithelium cells as these cells secrete mucous which prevents the organs from drying up and also protects against bacterial invasion.
iii) Oral cavity- Oral cavity comprises the mouth, oesophagus. These organs need lubrication for the passage of food. So, the lining of the oral cavity is made up of non-keratinised squamous epithelium cells. The mucus secreted by the cells play an important role in lubrication and protection.

Thus, the correct answer is option ‘D’.

Note: In non-keratinised squamous epithelium cells, the cells are arranged in layers on a basal membrane. The basal membrane is attached to a basement membrane which is capable of self-renewal. The cornea of eyes, anal canal, internal portion of lips is made up of non-keratinised squamous epithelium cells.