Complex Patterns of Inheritance A Many patterns of

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Complex Patterns of Inheritance A

Complex Patterns of Inheritance A

Many patterns of inheritance are not as simple as Mendel proposed. Many traits result

Many patterns of inheritance are not as simple as Mendel proposed. Many traits result from alleles with a range of dominance, rather than strict dominance and recessive relationship. Some traits are a result of the interaction of several genes.

INCOMPLETE DOMINANCE occurs when two homozygous parents produces a heterozygous offspring that is somewhere

INCOMPLETE DOMINANCE occurs when two homozygous parents produces a heterozygous offspring that is somewhere between the two parents. ---- has a blending affect. red white X pink

INCOMPLETE DOMINANCE ---- blending affect. What are the alleles? Red flower - R White

INCOMPLETE DOMINANCE ---- blending affect. What are the alleles? Red flower - R White flower - W red white pink WW RW X Genotype? RR x

Examples of Incomplete dominance

Examples of Incomplete dominance

CODOMINANCE occurs when both alleles from the parents are equally and separately expressed. Copilot….

CODOMINANCE occurs when both alleles from the parents are equally and separately expressed. Copilot…. . Cooperate homozygous white flower homozygous red flower red & white flower X Both the red and white alleles are separately visible.

CODOMINANCE - - - both alleles are visible What are the alleles? Red flower

CODOMINANCE - - - both alleles are visible What are the alleles? Red flower - R White flower - W red flower white flower red & white flower WW RW X Genotype? RR x

Examples of Codominance

Examples of Codominance

Example of Codominance - - - Blood types Blood Type A and Type B

Example of Codominance - - - Blood types Blood Type A and Type B are equally dominant. Type O is recessive. Alleles: IA IB IA & IB i

 Many genes may interact to produce one trait. Polygenic traits are traits produced

Many genes may interact to produce one trait. Polygenic traits are traits produced by two or more genes. Examples of polygenic traits in humans include: skin color (three genes) eye color (three genes) hair color (five genes) height (several).

The environment interacts with genotype. An individual’s phenotype is more than the sum of

The environment interacts with genotype. An individual’s phenotype is more than the sum of their genes. An individual’s phenotype often depends on conditions in the environment. Height in humans also depends on nutrition winter coat Arctic Fox summer coat

Incomplete or Codominance

Incomplete or Codominance

Incomplete or Codominance

Incomplete or Codominance

Incomplete or Codominance

Incomplete or Codominance

Incomplete or Codominance

Incomplete or Codominance

Incomplete or Codominance

Incomplete or Codominance

Incomplete or Codominance

Incomplete or Codominance

Incomplete or Codominance

Incomplete or Codominance

Incomplete or Codominance

Incomplete or Codominance

Incomplete or Codominance

Incomplete or Codominance

Sex-linked Inheritance A sex-linked gene in a gene located in a sex chromosome. Genes

Sex-linked Inheritance A sex-linked gene in a gene located in a sex chromosome. Genes on the Y-chromosome are found only in males and are passed directly from father to son. Genes located on the X-chromosome are found in both males and females.