Flower Genetics and Codominance Concepts

The lecture explains codominance, where both alleles are equally expressed, using a flower color example. In the F1 generation, crossing red and white flowers results in pink flowers, demonstrating codominance. The F2 generation shows a 1:2:1 ratio of red, pink, and white flowers, illustrating the genetic principles of homozygous and heterozygous alleles.

What is the key characteristic of codominance?

• One allele is recessive.

• Neither allele is expressed.

• Both alleles are expressed equally.

• One allele is dominant over the other.

In the example given, what are the parental phenotypes?

• One red flower and one white flower

• Two white flowers

• Two red flowers

• One pink flower and one white flower

What is the genotype for the red flower in the parental generation?

• CRCR

• CR

• CW

• CWCW

What is the phenotype of the F1 generation when a red and a white flower are crossed?

• Red flowers

• No flowers

• White flowers

• Pink flowers

What is the genotype of the F1 generation in the example?

• CWCW

• CRCWCR

• CRCW

• CRCR

In the F2 generation, what percentage of the flowers are pink?

• 75%

• 50%

• 25%

• 100%

What is the genotype of the pink flowers in the F2 generation?

• CRCR

• CWCW

• CRCW

• CRCRCW

What percentage of the F2 generation flowers are red?

• 50%

• 100%

• 75%

• 25%

What is the genotype of the white flowers in the F2 generation?

• CRCRCW

• CRCW

• CWCW

• CRCR

What does the F2 generation demonstrate about codominance?

• One allele is always dominant.

• Neither allele is expressed.

• Both alleles are expressed equally in some offspring.

• Only one allele is expressed.