Polygenic and Monogenic Inheritance Concepts

The video discusses polygenic inheritance, where multiple genes influence a single trait, unlike monogenic inheritance. Examples include skin color, height, and intelligence in humans. The video explains how environmental factors affect these traits and provides a detailed example of skin color inheritance, involving genes A, B, and C. It also covers genetic combinations and phenotypic ratios, comparing them with monogenic inheritance ratios.

What is the main difference between polygenic and monogenic inheritance?

• Monogenic inheritance involves a single gene affecting multiple traits.

• Polygenic inheritance involves multiple genes affecting a single trait.

• Monogenic inheritance involves multiple genes affecting a single trait.

• Polygenic inheritance involves a single gene affecting multiple traits.

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

• Skin color

• Height

• Eye color

• Intelligence

What pigment is responsible for determining skin color in humans?

• Hemoglobin

• Chlorophyll

• Melanin

• Carotene

How many genes are involved in the production of melanin pigment in humans?

• One

• Two

• Three

• Four

In a cross between a Negro and a white individual, what is the expected skin color of the F1 generation?

• Intermediate

• Negro

• White

• Albino

How many types of gametes are produced by an individual with the genotype AaBbCc?

• Four

• Six

• Ten

• Eight

What is the phenotypic ratio in the F2 generation for a tri-hybrid cross in polygenic inheritance?

• 3:1

• 1:6:15:20:15:6:1

• 9:3:3:1

• 1:2:1

In a monohybrid situation, what is the phenotypic ratio for quantitative inheritance?

• 3:1

• 1:1

• 9:3:3:1

• 1:2:1

How does the phenotypic ratio change in a dihybrid situation for quantitative inheritance?

• 3:1

• 9:3:3:1

• 1:4:6:4:1

• 1:2:1

What can be inferred by observing the phenotypic ratios in polygenic inheritance?

• The mutation rate

• The number of genes involved

• The dominance of a single gene

• The environmental influence