Genetics

When is a gene is homozygous?

• When the alleles are the same
• When the alleles are different

Which gene is heterozygous?

• TT
• Tt
• rr
• YY

How many alleles does an individual have for each trait?

• 1
• 2
• 3
• 4

Tags

NGSS.HS-LS3-1

What type of inheritance do two alleles have if their traits blend together?

• Incomplete Dominance

• Co-Dominance

• Mendelian Inheritance (Complete Dominance)

• Homozygous Inheritance

A calico cat shows both the traits for orange fur and black fur. What kind of allele expression is this?

• Incomplete Dominance
• Co dominance
• Independent assortment
• Recessive inheritance

The different analogous genes are called

• traits
• pollinators
• alleles
• hybrids

A breed of chicken shows codominance for feather color. One allele codes for black feathers, another codes for white feathers. The feathers of heterozygous chickens of this breed will be:

• all black
• all white
• all gray
• speckled black and white

Tags

NGSS.HS-LS3-2

Colorblindness is more common in males than in females because the allele for colorblindness is

• dominant and located on the X chromosome.
• recessive and located on the Y chromosome.
• recessive and located on the X chromosome.
• recessive and located on the Y chromosome.    

Tags

NGSS.HS-LS3-1

What does heterozygous mean?

• An organism that has the same genes for a trait (TT or tt)
• An organism that has different genes for a trait (Tt)
• When neither gene is fully dominant; offspring is a mixture of both
• the different forms of a trait (hair color--> brown, blonde, red

An allele whose trait only shows up when no dominant allele is present.

• hidden allele
• dominant allele
• recessive allele
• present allele