Question

Which of the subsequent are the derivatives of skin?
a. Hair
b. Nails
c. Both A and B
d. Feet

Answer 1

Hint: Human skin is the soft, outer covering of the body and is the largest organ of the system that covers the entire human body. Epidermis, Dermis, and hypodermis are the three layers of skin. The skin is a two-part organ that develops from several embryonic regions. The skin has many functions most importantly- protection, regulation, and sensation.

Complete answer:
Components of the integument include -
Skin - epidermis, dermis, hypodermis
Derivatives of the skin include- sweat glands, sebaceous glands, mammary glands, hair, nails, and follicles. All are epidermal invaginations into the dermis.

Functions of the skin are-
> Protection - It protects the skin from drying out and from invasion by microorganisms, from UV light.
> Sensation - It provides sensation for touch, pressure, pain, and temperature.
> Thermoregulation - It decreases heat loss in cold temperatures; increases heat loss in hot temperatures
> Metabolic functions - It helps to store the energy in form of fat deposits; synthesis of vitamin D
Hence, Hair and nails, both are derivatives of skin.

So, the correct answer is option (C).

Additional information:
The epidermis is the outermost layer of skin.
The dermis which is located beneath the epidermis, contains tough connective tissue, sweat glands, and hair follicles.
The innermost layer which is called the deeper subcutaneous tissue (hypodermis) is made up of fat and connective tissue.

Epidermal derivatives (also called epidermal appendages) develop from the epidermis but are located within the dermis. The most common epidermal derivatives are hair follicles, which produce hair on most of the body's surface.

The glands of the skin are all exocrine. Being exocrine, they secrete their products through the ducts to the epidermal surface. They may be unicellular, as are the goblet cells of fishes, or multicellular, as are the sweat glands of humans.

Note: The outer layer of skin (epidermis) originates from the embryonic ectoderm, whereas the inner layers of skin (dermis and subcutis) originate from the embryonic mesoderm. Pigment cells (melanocytes) migrate into developing skin from the embryonic "neural crest". The skin and its derivatives have various functions such as protecting the internal organs and tissues.