Hint: Testis is the male reproductive gland in animals. It produces sperm which is a male sex cell and sex hormones mainly the testosterone. The testes hang outside the body in a sac like structure called the scrotum. The testis produces sperms by the process called spermatogenesis.
Histology of testis- Testis is an oval egg like structure present in the man. They are two in number. The testis is a highly complex structure which is made up of three layers called the Tunica vaginali, Tunica vasculosa and Tunica albuginea.
Each testis contains several compartments called the testicular lobule. The lobules contain 1-3 coiled seminiferous tubules. These tubules produce sperm. The seminiferous tubules are made up of stratified epithelium which consists of sertoli cells and male germ cells. These cells divide and produce spermatozoa. The leydig cells are also present in between the tubules which secrete testosterone.
Sperm- The testes produce sperms by the process of spermatogenesis. The process of spermatogenesis is regulated by the hormone testosterone.
Structure of sperm-
1.A sperm is a microscopic tadpole-shaped cell. It consists of
Oval head which contains nucleus. It contains haploid chromosomes. It has an acrosomal head which helps in penetration into the egg.
2.A cylindrical body which contains mitochondria which provides energy for the movement of sperm.
3.An elongated flagella like tail which is highly motile and contains cytoplasm.
Note: The sperm is ejaculated in the form of semen through penis. A normal ejaculate contains around 500million sperms. Semen is made up of water, vitamin, zinc, proteins, vitamin C and prostaglandins.