Genetics: Co-dominance and Incomplete Dominance

The video tutorial explains how to solve genetic problems involving incomplete dominance and codominance using Punnett squares. It provides examples with cattle and rabbits to illustrate how different alleles are expressed in offspring. Codominance is demonstrated with cattle coloration, where both red and white alleles are expressed, resulting in roan cattle. Incomplete dominance is shown with rabbit fur color, where black and white alleles blend to produce gray offspring. The tutorial guides viewers through setting up Punnett squares to predict offspring genotypes and phenotypes.

What is the primary purpose of using a Punnett square in genetics?

• To determine the physical traits of parents

• To predict the genotypes of offspring

• To calculate the age of an organism

• To identify the species of an organism

In co-dominance, how are alleles expressed in the phenotype?

• Only one allele is expressed

• Alleles blend to form a new trait

• Neither allele is expressed

• Both alleles are expressed equally

What is the genotype of a roan cow in the given example?

• RR

• WW

• WR

• RW

What percentage of offspring from two roan cattle are expected to be roan?

• 100%

• 50%

• 25%

• 75%

In the context of the video, what does incomplete dominance result in?

• Equal expression of both traits

• No expression of either trait

• Dominance of one trait over the other

• A blend of both parental traits

What is the expected color of offspring from a black and a white rabbit showing incomplete dominance?

• White

• Spotted

• Gray

• Black

What is the genotype of the offspring when a black rabbit (BB) mates with a white rabbit (bb) under incomplete dominance?

• BB

• bb

• Bb

• bB

How many offspring from the black and white rabbit mating are expected to be gray?

• 0%

• 100%

• 25%

• 50%

What is the key difference between co-dominance and incomplete dominance?

• Co-dominance and incomplete dominance are the same.

• Co-dominance results in no trait expression, while incomplete dominance shows one trait.

• Co-dominance shows both traits equally, while incomplete dominance results in a blend of traits.

• Co-dominance results in a blend of traits, while incomplete dominance shows both traits equally.

Which of the following is an example of co-dominance?

• A red flower from red and white parents

• A gray rabbit from black and white parents

• A black and white spotted cow

• A pink flower from red and white parents