Chapter 11 Introduction to Genetics

Julianna Archacki

Alexandria Tsang

11-1 The Work of Gregor Mendel

11-1 The Work of Gregor Mendel

Gregor Mendel’s peas

Genes and Dominance A trait like seed color or plant

height. The offspring of crosses between

parents with different traits is hybrid.

Gregor Mendel’s peas

Genes and Dominance A trait like seed color or plant

height. The offspring of crosses between

parents with different traits is hybrid.

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Segregation is separation of alleles during gamete formation.

Gamete is a cell involved in sexual reproduction.

Segregation is separation of alleles during gamete formation.

Gamete is a cell involved in sexual reproduction.

11-2 Probability and Punnett Squares

11-2 Probability and Punnett Squares

• Genetics and probability Probability can be used to measure the outcome of

genetic crosses.

• Punnett Squares BB,bb is Homozygous.

Bb is Heterozygous.

All the tall plants have the same Phenotype. Genotype is genetic makeup of an organism.

• Genetics and probability Probability can be used to measure the outcome of

genetic crosses.

• Punnett Squares BB,bb is Homozygous.

Bb is Heterozygous.

All the tall plants have the same Phenotype. Genotype is genetic makeup of an organism.

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11-3 Exploring Mendelian Genetics

11-3 Exploring Mendelian Genetics

» Independent Assortment The genes for different traits can segregate

independently during the formation of gametes.

» Incomplete Dominance One allele is not completely dominant over another.

» Codominance Both alleles give to the phenotype of the

organism.

Multiple Alleles means genes more than 2 alleles then others.

Polygentic Traits means traits controlled by 2 or more genes. Many traits are made by the interaction of different genes.

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11-4 Meiosis11-4 Meiosis

• Meiosis is a process of reduction division in which the number of chromosomes per cell is cut in half through the separation of homologous chromosomes in a diploid cell.

• Meiosis is a process of reduction division in which the number of chromosomes per cell is cut in half through the separation of homologous chromosomes in a diploid cell.

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11-5 Linkage and Gene Maps

The chromosomes assort independently; individual genes do not.