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sexual reproduction. Sexual Reproduction. S.R. requires two parents S.R. produces offspring that are genetically different from each other, from either parent, and from any other member of their species. Sexual Reproduction. Genetic differences in a species is called genetic diversity .
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Sexual Reproduction • S.R. requires two parents • S.R. produces offspring that are genetically different from each other, from either parent, and from any other member of their species.
Sexual Reproduction • Genetic differences in a species is called genetic diversity. • Genetic diversity is the result of sexual reproduction, which randomly shuffles DNA.
Sexual Reproduction • We receive our genes from both of our parents. • Because we are genetically unique we may be better equipped to deal with changes in the environment than some other members of our species. • This is how one organism of a species can gain an advantage over another organism of the same species. (its called evolution)
Question • Q: How many chromosomes are in each of your cells?
Question • Q: How many chromosomes are in each of your cells? • A: 46
Question • Q: How many chromosomes are in each of your cells? • A: 46 • Q: So, where did you get your genes from again?
Question • Q: How many chromosomes are in each of your cells? • A: 46 • Q: So, where did you get your genes from again? • A: Your mom and dad
Question • Q: How many chromosomes are in each of your cells? • A: 46 • Q: So, where did you get your genes from again? • A: Your mom and dad • Wait a minute!! I’m confused.
Question • Q: If mom has 46 chromosomes in each of her cells.
Question • Q: If mom has 46 chromosomes in each of her cells. 46
Question • Q: If mom has 46 chromosomes in each of her cells. And dad has 46 chromosomes in each of his cells. 46
Question • Q: If mom has 46 chromosomes in each of her cells. And dad has 46 chromosomes in each of his cells. 46 46
Question • Q: If mom has 46 chromosomes in each of her cells. And dad has 46 chromosomes in each of his cells. How many chromosomes do I have? 46 46
Question • Q: If mom has 46 chromosomes in each of her cells. And dad has 46 chromosomes in each of his cells. How many chromosomes do I have? 46 46 92?
Question • Q: If mom has 46 chromosomes in each of her cells. And dad has 46 chromosomes in each of his cells. How many chromosomes do I have? 46 46 92? This can’t be right!!!
Sexual Reproduction • Each human has inherited 23 chromosomes from their mother, and 23 chromosomes from their father. • These 23 chromosomes are carried in specialized cells called gametes.
Sexual Reproduction • In animals, male gametes are called sperm cells. • Female gametes are called egg cells.
Sexual Reproduction • During a process called fertilization an egg cell is penetrated by a sperm cell and the genetic information of both male and female gametes combines.
Sexual Reproduction • During a process called fertilization an egg cell is penetrated by a sperm cell and the genetic information of both male and female gametes combines. 23 23 46
Question • Q: So, how do the gametes get only 23 chromosomes in them?
Question • Q: So, how do the gametes get only 23 chromosomes in them? • A: in a process called...
Comparing Sexual and Asexual Reproduction Asexual Reproduction Sexual Reproduction Two parents Few, to many offspring Offspring are genetically different Offspring are usually produced quite slowly Can be done when mature, but only when a mate is available • One parent • Usually many offspring • Offspring are genetically identical • Offspring can be produced very quickly • Can be done anytime once organism is mature.