Dihybrid Cross Mastery

Curly hair and dimples are both considered dominant human traits. What are the expected phenotypes of the offspring of the following two individuals?

• Female with curly hair and no dimples (Ccdd)

• Male with straight hair and dimples (ccDd)?

1. 1. What percentage would have curly hair and dimples?

2. 2. What percentage would have curly hair and no dimples?

Tags

NGSS.HS-LS3-1

NGSS.HS-LS3-2

NGSS.HS-LS3-3

In the 1860s Gregor Mendel performed numerous dihybrid crosses between pea plants. Dihybrid crosses involve the study of the inheritance patterns related to two different traits.In rabbits, the allele for black fur (B) is dominant over the allele for white fur (b), and the allele for long ears (L) is dominant over the allele for short ears (l).

What percentage of the offspring from a BbLl × bbll cross would be expected to be heterozygous for both traits?

• 100%

• 75%

• 25%
• 0%

• 50%

A dog breeder repeatedly mates a black-furred, short-tailed dog (B?tt) with a white-furred, long-tailed dog (bbT?). In order to assure the breeder that both parents are homozygous for their traits, what percentage of their offspring would need to be black-furred and long-tailed?

• 100%

• 25%

• 50%

• 0%

• 75%

Tags

NGSS.HS-LS3-1

NGSS.HS-LS3-2

NGSS.HS-LS3-3

A dog breeder repeatedly mates a black-furred, short-tailed dog (B?tt) with a white-furred, long-tailed dog (bbT?). If the black fur tailed remained homozygous but the white-furred, long-tailed dog ended up being heterozygous for tail length, what phenotypes could you possibly see among the offspring? Choose all that apply.

• white-furred, short-tailed
• white-furred, long-tailed
• black-furred, short-tailed

• black-furred, long-tailed;

Tags

NGSS.HS-LS3-1

NGSS.HS-LS3-2

Freckles and the ability to roll your tongue are inherited human traits. Freckles (F) are dominant to no freckles (f), and the ability to roll your tongue (B) is not being able to roll your tongue (b). Both parents are heterozygous for both traits.

What would be the genotype of an offspring with no freckles and not being able to roll your tongue?

• ffbb
• FfBb
• FFBB
• ffBb

Tags

NGSS.HS-LS3-1

NGSS.HS-LS3-2