Genetics practice study guide

An offspring will receive how many alleles from each parent to determine a specific trait?

• one
• two
• three
• five

Which of the following is a phenotype?

• BB
• Bb
• bb
• Blue eyes

having two of the same genes for the trait (sometimes called purebred).

• homozygous
• hetrozygous
• protein
• chromosome

Incomplete dominance means that the traits are

• expressed equally
• dominant
• recessive
• blended

One form of a gene is called_______________

• a DNA
• a Phenotype
• a trait
• an allele

If green is dominant over purple, then what is the genotype for this individual?

• Purple
• Green
• GG
• gg

In pea plants, the tall allele is dominant to the short allele. What key would demonstrate this?

• Tall = T
  Short = S
• Tall = T
  Short = t
• Tall = t
  Short = T
• Tall = TT
  Short = tt

A heterozygous long-tusked elephant is crossed with a homozygous recessive short-tusked elephant. What is the probability of the offspring having short tusks?

• 0%
• 25%
• 50%
• 75%

Which of the following genotypes is homozygous dominant?

• Yy

• yY

• yy

• YY

What is the genotypic ratio of the offspring?

• 3:1

• 1:3

• 1:2:1

• 2:2