Law of Dominance

The video tutorial explains the concept of inheritance, focusing on dominant and recessive traits, using eye color as an example. It delves into Mendel's experiments with pea plants, illustrating the law of dominance and the 3:1 phenotypic ratio. The tutorial also covers incomplete dominance, using Snapdragon flowers and chicken plumage as examples, highlighting the 1:2:1 phenotypic ratio. Finally, it discusses codominance in human ABO blood groups, explaining how both alleles are expressed equally, resulting in a 1:2:1 ratio.

What determines the eye color of children when one parent has brown eyes and the other has blue eyes?

• The eye color of the mother

• The eye color of the father

• The recessive gene for blue eyes

• The dominant gene for brown eyes

What did Mendel's experiments with pea plants demonstrate about inheritance?

• Traits are controlled by discrete units called factors

• Traits are determined by a single parent

• Traits are inherited randomly

• Traits are always dominant

In Mendel's pea plant experiments, what was the observed ratio of tall to dwarf plants in the F2 generation?

• 1:1

• 3:1

• 4:1

• 2:1

What is the result of crossing red and white Snapdragon flowers?

• All white flowers

• All red flowers

• No flowers

• Pink flowers

What is the phenotypic ratio for incomplete dominance?

• 2:1

• 3:1

• 1:2:1

• 1:1

In the context of codominance, what blood group results from the presence of both IA and IB alleles?

• Blood group A

• Blood group B

• Blood group AB

• Blood group O

Which alleles are considered codominant in the ABO blood group system?

• IB and i

• IA and IB

• IA and i

• i and i

What is the genotypic and phenotypic ratio for offspring when both parents have blood group AB?

• 1:2:1

• 3:1

• 2:1

• 1:1

How does the phenotypic ratio in codominance differ from Mendel's monohybrid cross?

• It is the same

• It is 1:1

• It is 1:2:1

• It is 2:1

What is the key difference between incomplete dominance and codominance?

• Both show only one trait

• Both show a blend of traits

• Incomplete dominance shows both traits, codominance results in a blend

• Incomplete dominance results in a blend, codominance shows both traits