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Chapter 11 Review. Meiosis and Sexual Reproduction. Meiosis. Occurs in all sexually reproducing organisms. Genetic Variation. Contributes to genetic variation: Random fertilization Independent assortment Crossing over Binary Fission does not lead to genetic variations. Haploid - Diploid.
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Chapter 11 Review Meiosis and Sexual Reproduction
Meiosis • Occurs in all sexually reproducing organisms
Genetic Variation • Contributes to genetic variation: • Random fertilization • Independent assortment • Crossing over • Binary Fission does not lead to genetic variations.
Haploid - Diploid • In the alternation of generations, spores, gametophytes and egg and sperm are Haploid • Sporophytes are Diploid
Meiosis • Two successive divisions are responsible for the formation of four haploid cells.
Asexual Reproduction • DNA does not vary much between offspring • Many offspring are produced in a short time • Organisms may not be able to adapt to new environments
Fragmentation • Is a form of asexual reproduction
Gametes • In humans, each gamete receives one chromosome from each of 23 pairs
Crossing Over • Portions of a chromatid on one homologous chromosome break off and trade places with the corresponding portion on one of the chromatids of the other homologous chromosome
Life Cycle • The activities in the life of an organism from one generation to the next.
Diploid • A cell that contains two sets of chromosomes
Independent Assortment • Random distribution of homologous chromosomes during meiosis
Homologous Chromosomes • Chromosomes that are similar in shape and size and have similar gentetic information
Spermatogenesis • The process by which gametes are produced in male animals
Haploid • A cell that contains one set of chromosomes
Oogenesis • The process by which gametes are produced in female animals
Fertilization • The union of sperm and egg cells to produce a diploid zygote
Asexual Reproduction • All copies of the single parent’s genes are passed to the offspring
Ovum • Female gamete, also called an egg
Test Chapter 11 • Tomorrow