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Sex Cells & Meiosis. Pages 275 - 278. Sex Cells. Gametes = sperm and egg (sex cells) Testes produce sperm Ovaries produce eggs Why are gametes made? To pass on genetic info (chromosomes) to offspring How are gametes made? MEIOSIS! (a special type of cell division). Testes. Ovaries.
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Sex Cells & Meiosis Pages 275 - 278
Sex Cells • Gametes= sperm and egg (sex cells) • Testesproduce sperm • Ovariesproduce eggs • Whyare gametes made? • To pass on genetic info (chromosomes) to offspring • Howare gametes made? • MEIOSIS! (a special type of cell division)
Testes Ovaries MEIOSIS MEIOSIS Sperm Egg Zygote MITOSIS Human
Homologous Chromosomes • Pair of chromosomes that carry the same genes at the same location • 1 comes from mom (egg) • 1 comes from dad (sperm) • In humans there are 23 pairs of homologous chromosomes (46 total)
Mitosis vs. Meiosis growth & repair many parts of body body cells (ex: skin) 1 2 46
Mitosis vs. Meiosis growth & repair reproduction many parts of body testes & ovaries body cells (ex: skin) gametes 1 2 2 4 23 46
How many chromosomes are there? • How many pairs of chromosomes are there? • Is this human male or female?
Review • How many chromosomes are there in human body cells? 46 chromosomes • How many chromosomes are in human gametes? 23 chromosomes • How are many types of body cells made? Mitosis • How are gametes (sex cells) made? Meiosis – occurs in the ovaries & testes • What do we call a pair of chromosomes that have the same genes at the same location? Homologous chromosomes