In humans, male sex cells or spermatozoa sperm cells , are relatively motile. Female sex cells, called ova or eggs, are non-motile and much larger in comparison to the male gamete. Male and female sex cells are dramatically different from one another in size and shape.
The male reproductive system consists of a number of sex organs that play a role in the process of human reproduction. These organs are located on the outside of the body and within the pelvis. The main male sex organs are the penis and the testicles which produce semen and sperm , which, as part of sexual intercourse , fertilize an ovum in the female's body; the fertilized ovum zygote develops into a fetus , which is later born as an infant. The corresponding system in females is the female reproductive system. The penis is the male intromittent organ. It has a long shaft and an enlarged bulbous-shaped tip called the glans penis , which supports and is protected by the foreskin. When the male becomes sexually aroused , the penis becomes erect and ready for sexual activity. Erection occurs because sinuses within the erectile tissue of the penis become filled with blood. The arteries of the penis are dilated while the veins are compressed so that blood flows into the erectile cartilage under pressure. The penis is supplied by the pudendal artery.
The bodies of most animals and plants contain body somatic cells, eg skin cells, nerve cells, liver cells etc and gametes sex cells. The body cells of most animals and plants each contain two sets of chromosomes in their nuclei. Every chromosome in one set has a matching partner in the other set that has the same length of DNA and the same genes. Cells that contain two sets of chromosomes are said to be diploid. In sexual reproduction new organisms are produced from the fusing of the nucleus of a male sex cell with the nucleus of a female sex cell. This is called fertilisation.
Reproduction is the process by which organisms make more organisms like themselves. But even though the reproductive system is essential to keeping a species alive, unlike other body systems, it's not essential to keeping an individual alive. In the human reproductive process, two kinds of sex cells, or gametes GAH-meetz , are involved. The male gamete, or sperm, and the female gamete, the egg or ovum, meet in the female's reproductive system. When sperm fertilizes meets an egg, this fertilized egg is called a zygote ZYE-goat. The zygote goes through a process of becoming an embryo and developing into a fetus. The male reproductive system and the female reproductive system both are needed for reproduction. Humans, like other organisms, pass some characteristics of themselves to the next generation.