Question

Assertion Stratum germinativum is called so because of fast mitotic divisions.
Reason: All the cutaneous glands are therefore formed from this layer.
A. Both Assertion and Reason are correct and Reason is the correct explanation for Assertion.
B. Both assertion and Reason are correct but Reason is not the correct explanation for Assertion.
C. Assertion is correct but Reason is incorrect.
D. Both Assertion and Reason are incorrect.

Answer 1

Hint: Stratum germinativum (also called stratum basale) is the deepest epidermal layer consisting of a single row of basal cells, or germinative cells, that are undergoing rapid mitotic divisions. There are two types of cutaneous glands found in the dermis: sebaceous glands and sweat glands.

Complete Answer:
The stratum germinativum is the deepest epidermal layer. It provides the germinal cells necessary for the regeneration of the layers of the epidermal layers. Basal cells can act like stem cells due to their ability to divide and produce new cells. These are sometimes called basal keratinocyte stem cells. The cell division here is mitotic. Sebaceous glands are visible from the 13th to the 16th week of fetal development and develop from the same tissue that gives rise to the epidermis of the skin. Likewise, sweat glands are also an extension of epidermis. This indicates that both the stratum germinativum and the cutaneous glands have arisen from the epidermis which follows mitotic cell division to expand.

Thus, option (A), both Assertion and Reason are correct and Reason is the correct explanation for Assertion.

Note:
Sebaceous glands or oil glands are present all over the skin, except on the palms of the hands and the soles of the feet. The sweat glands are widely distributed over the skin and assists in the heat regulation of the body. The stratum germinativum is a single layer of columnar or cuboidal basal cells that are attached to each other and are overlying stratum spinosum cells by desmosomes and hemidesmosomes.