ANATOMY

Detailed explanation-1: -Natural levels of growth hormone fluctuate during the day, seemingly influenced by physical activity. For example, levels rise when we exercise. Growth hormone levels increase during childhood and peak during puberty. In this phase of development, growth hormone promotes the growth of bone and cartilage.

Detailed explanation-2: -Growth hormone levels are increased by sleep, stress, exercise and low glucose levels in the blood. They also increase around the time of puberty. Growth hormone release is lowered in pregnancy and if the brain senses high levels of growth hormone or insulin-like growth factors already in the blood.

Detailed explanation-3: -Growth hormone (GH) or somatotropin, also known as human growth hormone (hGH or HGH) in its human form, is a peptide hormone that stimulates growth, cell reproduction, and cell regeneration in humans and other animals. It is thus important in human development.

Detailed explanation-4: -Growth hormone (GH) promotes stem cell activation, cell proliferation, differentiation and survival, either directly or through the induction of IGF-1.

Detailed explanation-5: -As the radius of a cell increases, its surface area increases as the square of its radius, but its volume increases as the cube of its radius (much more rapidly). Therefore, as a cell increases in size, its surface area-to-volume ratio decreases.