The Reproductive System Essay

1026 Words 5 Pages
The Reproductive System

The male and female reproductive systems are different with both having specific roles.

The Male Reproductive System ============================

The main structures of the male reproductive system are the testes, the penis and several glands. Male sperm carries genetic information and are produced continually from the start of puberty. The primary spermatocyte divides by meiosis make two secondary spermatocytes and then four, which have half the amount of chromosomes as the mother cell (46 in humans) therefore sperm (spermatozoa) has 23 chromosomes (genetic information).

Sperm produced in the testes in a sac called the scrotum is 3°C cooler than
…show more content…
Semen is composed of sperm and secretions from the prostate gland and other glands that provide energy for the sperm.

The penis is an external tube containing three distensible rods of spongy tissue that extends the length of the penis. At its centre is the urethra, which passes urine and semen. The spongy tissue in the penis inflates, there are small spaces between the cells. The central nervous system sends signals in the form of nerve impulses that cause the arterioles to expand and blood collects in the spaces within the spongy tissue (corpus spongiosum and corpora cavernos). This makes the penis rigid and continuous stimulation from the central nervous system is required for the erection to be maintained.

Although physical stimulation is not necessary for an erection it is necessary for semen to be delivered from the penis. Repeated thrust into the vagina of the female leads to the mobilisation of sperm. Muscles encircling the vas deferens contract moving sperm into the urethra. Stimulation eventually leads to the violent contractions of muscles at the base of the penis, resulting in ejaculation (the forceful ejaculation of semen out of the penis). Only a small amount is delivered but it contains several hundred million sperm cells. During ejaculation the sphincter at the base of the bladder is closed, therefore no
Open Document