Monohybrid Crosses Practice

Which of the following traits of a dog is inherited from its parents?

• the presence of fleas in its fur

• the color of its fur

• the ability to sit up and beg

• the habit of barking to go outside

The physical expression of a genetic trait is called a

• mutation

• genotype

• crossing over

• phenotype

The following items are examples of __________.

Items: eye color, hair color, height

• homozygous alleles

• genotype

• heterozygous alleles

• phenotype

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

• homozygous
• hetrozygous
• protein
• chromosome

B=brown eyes
b= blue eyes
What is true about these two brothers that have brown eyes:
One has genotype BB the other Bb.

• they have same phenotype and genotype
• they have different genotypes and phenotypes
• they have same phenotype but different genotypes
• they have same genotype but different phenotypes

Two brown eyed parents (Bb) have a baby. What is the chance the baby is blue eyed? (B=brown eyes and b=blue eyes)

• 0 %

• 25%

• 50%

• 75%

Tall is dominant to short. A homozygous tall plant is crossed with a short plant. What will be the phenotypes of the offspring?

• 100% tall
• 50% tall, 50% short
• 75% tall, 25% short
• 25% tall, 75% short

Green is dominant to yellow. Two heterozygous green plants are crossed. What are the genotypes of the offspring?

• 100% Gg
• 50% GG, 50% Gg
• 25% GG, 50% Gg, 25% gg
• 75% Gg, 25% gg

Tall is dominant to short. A homozygous tall plant is crossed with a short plant. What will be the phenotypes of the offspring?

• 100% tall
• 50% tall, 50% short
• 75% tall, 25% short
• 25% tall, 75% short

Which of the following genotypes would be considered heterozygous?

• BB
• gg
• Ff
• TT