Write a short note on Reproductive Glands (Gonads) of Humans and Thymus Gland

• The reproductive glands, also known as gonads, play a crucial role in human reproduction by producing sex cells and essential hormones.
• The sex glands are of two types the testes and the ovaries. 
• The testes are present in males, while the ovaries are present in females.

Testes

• The testes, also commonly referred to as testicles, are two oval-shaped glands located in the scrotum, a pouch of skin behind the penis. They play a crucial role in the male reproductive system
• They are composed of seminiferous tubules, Leydig cells and Sertoli cells. 
• Leydig cells form the endocrine part of the testes. They secrete the male sex hormone called testosterone.

Functions of testosterone

• It influences the process of spermatogenesis.  
• It stimulates protein synthesis and controls muscular growth.
• It is responsible for the development of secondary sexual characteristics (distribution. of hair on the body and face, deep voice pattern, etc).

Ovary

• The ovaries are the female gonads located in the pelvic cavity of the abdomen. They secrete the female sex hormones

Estrogen

• Estrogen is produced by the Graafian follicles of the ovary and progesterone from the corpus luteum that is formed in the ovary from the ruptured follicle during ovulation.

Functions of estrogens

• It brings about the changes that occur during puberty.
• It initiates the process of oogenesis.
• It stimulates the maturation of ovarian follicles in the ovary.
• It promotes the development of secondary sexual characters (breast development, high-pitched voice etc).

Functions of progesterone

• It is responsible for the premenstrual changes of the uterus.
• It prepares the uterus for the implantation of the embryo.
• It maintains pregnancy.
• It is essential for the formation of the placenta.

Thymus Gland

• The thymus is partly an endocrine gland and partly a lymphoid gland. 
• It is located in the upper part of the chest covering the lower end of the trachea. 
• Thymosin is the hormone secreted by the thymus.

Functions of Thymosin

• The primary function of the thymus gland is to produce and train T lymphocytes, a type of white blood cell responsible for cell-mediated immunity.
• T cells help the body fight off infections, viruses, bacteria, and even cancer cells.
• The thymus also produces hormones, such as thymosin, which influence the development and function of T cells and other immune cells.