Which plane divides the body into the right and left sides?.

Absorption of calcium from the digestive tract. This is because vitamin D is essential for maintaining bone density and healthy bone growth, and it stimulates calcium and phosphate uptake from the food we eat. Vitamin D is produced when the skin is exposed to ultraviolet rays from the sun, which convert a precursor molecule in the skin to an active form that travels to the liver and kidneys.

Choice A is wrong because elimination of toxins from the blood is not related to vitamin D, but to the kidneys and liver functions.

Choice B is wrong because increase in red blood cell production is not related to vitamin D, but to erythropoietin, a hormone produced by the kidneys.

Choice D is wrong because conservation of water in the plasma is not related to vitamin D, but to antidiuretic hormone, a hormone produced by the pituitary gland.

Sebaceous glands are microscopic glands in the skin that secrete an oily or waxy substance called sebum into the hair follicles or onto the skin surface.

Sebum lubricates and protects the skin and hair from drying out and from infections caused by bacteria or fungi. Sebum also contributes to body odour.

A. To secrete cerumen or earwax. This statement is wrong because cerumen is produced by specialized sweat glands in the ear canal, not by sebaceous glands. B. To produce hair growth.

This statement is wrong because hair growth is determined by the activity of hair follicles, not by sebaceous glands. Sebaceous glands only deposit sebum on the hairs and bring it to the skin's surface.

D. To excrete perspiration or sweat.

This statement is wrong because perspiration is produced by sweat glands, not by sebaceous glands. Sweat glands are different from sebaceous glands in their structure, location and function. Sweat glands help regulate body temperature and eliminate waste products through the skin.

The left lung lies superior to the diaphragm and left of the mediastinum, which is the space between the lungs that contains the heart and other structures. The left lung is also smaller than the right lung because of the cardiac notch, which accommodates the heart.

Choice A is wrong because the spleen is an abdominal organ that lies inferior to the diaphragm and left of the stomach.

Choice C is wrong because the stomach is also an abdominal organ that lies inferior to the diaphragm and left of the spleen.

Choice D is wrong because the left kidney is another abdominal organ that lies inferior to the diaphragm and posterior to the spleen.

Testosterone is an androgen, a type of sex hormone responsible for developing male characteristics, such as pubic and axillary hair, deepening of the voice, growth of the penis, and sperm production. Testosterone is produced by the testes in males and the ovaries and adrenal glands in females.

Choice A is wrong because oxytocin is a hormone that stimulates uterine contractions during labor and milk ejection during breastfeeding.

It does not affect hair growth at puberty.

Choice B is wrong because progesterone is a hormone that prepares the endometrium for implantation and maintains pregnancy.

It does not affect hair growth at puberty.

Choice C is wrong because prolactin is a hormone that stimulates milk production in the mammary glands.

It does not affect hair growth at puberty.