Polygenic Inheritance and Genetic Traits

The video explores complex patterns of inheritance beyond Mendel's simple two-allele model. It covers four main patterns: incomplete dominance, where one allele is partially dominant; codominance, where both alleles are equally expressed; multiple alleles, where more than two alleles determine a trait; and polygenic inheritance, where multiple genes influence a trait. Examples include snapdragons, chicken feathers, rabbit fur, blood types, and human traits like height and skin color.

What did Mendel study in terms of inheritance?

• Traits controlled by multiple alleles

• Traits controlled by environmental factors

• Traits controlled by two alleles

• Traits controlled by a single allele

In incomplete dominance, what is the result of crossing a red Snapdragon with a white Snapdragon?

• Yellow Snapdragons

• White Snapdragons

• Red Snapdragons

• Pink Snapdragons

What percentage of offspring will be pink when two pink Snapdragons are crossed?

• 100%

• 75%

• 50%

• 25%

In codominance, what is the result of crossing a black chicken with a white chicken?

• Black chickens

• Gray chickens

• White chickens

• Chickens with black and white feathers

What is the expected percentage of black feathered offspring when two black and white feathered chickens are crossed?

• 25%

• 50%

• 75%

• 100%

What does the concept of multiple alleles refer to?

• Genes with only two possible alleles

• Genes with three or more possible alleles

• Genes with a single allele

• Genes influenced by environmental factors

Which of the following is an example of a trait determined by multiple alleles?

• Skin color

• Blood type

• Human height

• Eye color

What is polygenic inheritance?

• A trait controlled by a single allele

• A trait controlled by a single gene

• A trait controlled by environmental factors

• A trait controlled by multiple genes

Which of the following is NOT an example of polygenic inheritance?

• Cleft palate

• Human height

• Blood type

• Skin color

Which genetic disorder is mentioned as an example of polygenic inheritance?

• Hemophilia

• Sickle cell anemia

• Cystic fibrosis

• Diabetes