In addition to regulating the formation of sperms, testosterone, a hormone secreted by the testes, brings about changes in the appearance of boys during puberty. It plays a crucial role in the development of secondary sexual characteristics, such as facial ...

The testes are located outside the abdominal cavity in the scrotum because sperm formation requires a lower temperature than the normal body temperature. This arrangement helps maintain the optimal temperature for spermatogenesis.

The male reproductive system consists of portions responsible for producing germ-cells (sperms) and other portions that deliver these germ-cells to the site of fertilization.

Mammals, including humans, require specialized organs for the sexual act because the transfer of germ-cells between two individuals is essential for sexual reproduction. In mammals, the development of organs like the erect penis is crucial for successful mating, while the ...

Changes during puberty, such as new hair-growth patterns, serve as signals indicating that sexual maturation is occurring in animals. These signals help individuals identify the readiness of others for the process of mating.

The changes during puberty are linked to the reproductive process, particularly in organisms with a sexual mode of reproduction. They include signals of sexual maturation and the development of specialized organs necessary for the transfer of germ-cells between individuals.

Puberty is considered a distinct period in human development because it marks the transition from the primary focus on the growth of the individual organism to the initiation of the maturation process for reproductive tissues, preparing the body for sexual ...

The resources of the body are primarily directed towards achieving overall growth during the initial stages of development. As the rate of general body growth slows down, resources are then redirected towards the maturation of reproductive tissues.

Sexual maturation occurs during adolescence because, during this period, the body shifts its focus from rapid overall growth to the maturation of specialized tissues, particularly those related to reproduction.

Individual differences in the timing and pace of puberty-related changes contribute to unique patterns of hair growth, breast or penis size, and overall sexual maturation among people, similar to variations in other physical features like nose or finger shapes.