Question

Which one of the following directly helps in keeping the body warm?
A. Sweat glands
B. Adipose tissue
C. Connective tissue
D. Hairs

Answer 1

Hint: The characteristic feature of mammals is the presence of hairs on the skin to insulate from cold conditions and keep the body warm. But humans have evolved a special kind of tissue over the course of evolution and the hair is reduced and does not form thick fur as in the case of animals that live in cold climates like yaks, polar bears etc.

Complete answer:
Let us see and understand the different options given in the question and see the functions of each of the tissues and glands.
The first option is sweat glands. Sweat glands as the name suggests it is a gland present on the skin throughout the body. The main function of the sweat glands is to produce sweat and sweat helps to cool down the body in case of hot temperature in the surroundings. It also helps to excrete out a few salts and minerals.
The next tissue is the adipose tissue. Adipose tissue is called the natural insulator as it provides insulation to the body in cold conditions. The cells are called adipocytes. The main function of these cells is to store energy in the form of fat. Additionally, it insulates the body and also cushions it. Adipose tissues have three types of adipocytes; white, brown and beige. Brown adipocytes are involved in thermal insulation as it contains a high amount of fat.
Connective tissue is a general name given to the tissues that are involved in connecting, separating and supporting other tissues. It is present all over the body. It is a broad term and the examples include blood, cartilage, adipose tissue etc.
Hair, as mentioned in the hint is a thermal insulator but it is not present abundantly in all mammals. The functions of hair are protection, regulation of heat and also act as a sensory organ along with the skin.
Specifically, the adipose tissues are the main tissues that are involved in the insulation of the body and help keep the body warm.

Hence the right answer is option B – Adipose tissue.

Note:
Brown adipose tissues have a lot of mitochondria that are rich in iron and they have small lipid droplets that are many in number that give it a brown colour. Also, these mitochondria have higher concentration of thermogenin than normal cells. In infants, the body mass is almost made up of brown adipose tissue.