reproduction in humans real

Discovery Science: Earth – Humans – Reproduction

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Earth Science: Humans – Reproduction When humans reproduce, two differentiated germ cells (egg and sperm) merge. A new person develops from the fertilized egg-a process that takes approximately nine months. Before the germ cells merge, the genetic material-which in normal cells occurs as a set of two—is reduced to a single set of chromosomes. This … Read more

Discovery Science: Earth Biology – Humans – Reproductive Organs

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Earth Science: Humans – Development Human development begins when two gametes from the parents fuse to form the zygote. A new individual develops from the zygote over the course of about nine months. After puberty, humans are sexually mature and can reproduce. As the body ages, the efficiency and function of the organs gradually diminishes. … Read more