Biology Meiosis and Mitosis
AP Biology: Chapter 13 - Meiosis and Sexual Life Cycles
Overview * The transmission of traits from one generation to the next is called inheritance, or heredity * Along with inherited similarity there is also variation * Genetics is the scientific study of heredity and hereditary variation I. 13.1 Offspring Acquire Genes from Parents By Inheriting Chromosomes A. Inheritance of Genes * Parents endow their offspring with coded information in the form of hereditary units called genes * Most genes program cells to synthesize specific enzymes and other proteis, whose cumulative action produces an organism's inherited traits * In animals and plants, reproductive cells called gametes are the vehicles that transmit genes from one generation to the next * A gene's specific location along the length of a chromosome is called the gene's locus B. Comparison of Asexual and Sexual Reproduction * In asexual reproduction, a single individual is the sole parent and passes copies of all its genes to its offspring without the fusion of gametes * An individual that reproduces asexually gives rise to a clone, a group of genetically identical individuals * In sexual reproduction, two parents give rise to offspring that have unique combinations of genes inherited from the two parents II. 13.2 Fertilization and Meiosis Alternate In Sexual Life Cycles * A life cycle is the generation to generation sequence of stages in the reproductive history of an organism, from conception to production of its own offspring C. Sets of Chromosomes in Human Cells * In humans each somatic cell has 46 chromosomes * Karyotype is a display of the chromosomes pairs of a cell arranged by size and shape * Two chromosomes composing a pair have the same length, centromere position and staining pattern, these are called homologous chromosomes * The X and Y chromosomes are called the sex chromosomes * Other chromosomes are
Overview * The transmission of traits from one generation to the next is called inheritance, or heredity * Along with inherited similarity there is also variation * Genetics is the scientific study of heredity and hereditary variation I. 13.1 Offspring Acquire Genes from Parents By Inheriting Chromosomes A. Inheritance of Genes * Parents endow their offspring with coded information in the form of hereditary units called genes * Most genes program cells to synthesize specific enzymes and other proteis, whose cumulative action produces an organism's inherited traits * In animals and plants, reproductive cells called gametes are the vehicles that transmit genes from one generation to the next * A gene's specific location along the length of a chromosome is called the gene's locus B. Comparison of Asexual and Sexual Reproduction * In asexual reproduction, a single individual is the sole parent and passes copies of all its genes to its offspring without the fusion of gametes * An individual that reproduces asexually gives rise to a clone, a group of genetically identical individuals * In sexual reproduction, two parents give rise to offspring that have unique combinations of genes inherited from the two parents II. 13.2 Fertilization and Meiosis Alternate In Sexual Life Cycles * A life cycle is the generation to generation sequence of stages in the reproductive history of an organism, from conception to production of its own offspring C. Sets of Chromosomes in Human Cells * In humans each somatic cell has 46 chromosomes * Karyotype is a display of the chromosomes pairs of a cell arranged by size and shape * Two chromosomes composing a pair have the same length, centromere position and staining pattern, these are called homologous chromosomes * The X and Y chromosomes are called the sex chromosomes * Other chromosomes are