Unit 4 Day 2: Mendel's 2nd Law

Unit 4 Day 2: Mendel's 2nd Law

By jack morgan

Yesterday we learned that...​

• An organisms traits are determined by alleles​

• Each trait has a Dominant and a Recessive allele

• Mendel's First Law which is...

Multiple Choice

Mendel's First Law States that...

• The two alleles for a trait will separate during meiosis

• The two alleles for a trait will stay together during meiosis

• The two alleles for a trait cross over during meiosis

• The two alleles for a trait become dominant and recessive during meiosis

Discovering Mendel's 2nd Law​

Mendel didn't know if different alleles operated together as a unit or independently of each other​

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Mendel discovered that genes are sorted independently from each other​

Mendel's 2nd Law​- alleles in an organism are sorted independently of each other

​this is a punnett square for 2 alleles

The way we represent ​ALL the possible phenotypes of a cross between organisms is called a Punnett Square

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(named after ​Reginald C. Punnett)

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Multiple Choice

Punnett Squares allow us to predict...

• Probability of an Offspring's Genotypes only

• Probability of an Offspring's Phenotype only

• Probability of both

• Probability of neither

Mendel's First Law: an organisms two alleles of the same gene are split up during Meiosis

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Mendel's Second Law: Genes on seprate chromosomes are sorted independently of each other​

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In review​...

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Any Questions?​