Reproduction is the production of offspring by living organisms. Sexual reproduction is a biological process by which organisms create their descendants. These organisms are divided into two different sexes, male and female. Human reproduction is an example of sexual reproduction in which the male produces sperm, and the female produces eggs. Normally, only one mature egg is produced in every 28 day cycle. An unfertilized egg survives 3 to 4 days. Sperms are formed by the millions, and as many as 40 to 400 million sperm cells are released each time. Healthy sperm can survive 2 to 3 days in the female body. Fertilization normally takes place in the Fallopian tube, leading from the ovary to the uterus. Conception takes place when the egg is fertilized and pregnancy begins at this point. Sperm cells and eggs contain only half the normal number of chromosomes, 23 instead of 46, so that on fertilization the resulting cell has the correct genetic complement. Fertilization in human beings is internal, which increase the chances of conception.
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