Unit Test Answers

Which fraction represents 25% of the offspring in a genetic cross?

Being able to roll the tongue is dominant over not being able to roll the tongue.

Having freckles is dominant over not having freckles, and curly hair is dominant over straight hair. One parent is homozygous for freckles and has straight hair. The other parent does not have freckles and has straight hair.

In the 1950s, a fungus nearly wiped out an entire species of bananas that were produced through cloning.

Brown eye color is a dominant trait and blue eye color is a recessive trait.What typically happens when someone inherits one allele for brown eyes and one for blue eyes?

Some illnesses and harmful infections are caused by bacteria. These bacteria grow in the human body and often make people sick with symptoms like coughing, sneezing, and fever. These illnesses are not related to any genetic mutations or other problems with DNA.

Danielle has blonde hair. Her mother has blonde hair and her father has brown hair.Which explains how Danielle inherited her hair color?

A scientist has a tomato plant with red-skinned tomatoes. It has one allele for red skin (R) and one for yellow skin (r).Which describes the phenotype of the tomato plant?

Sherry draws a diagram to compare selective breeding and genetic engineering.

Why is decreased genetic variation in a species considered a negative impact of genetic technologies?

A cleft chin is a dominant trait. One parent is heterozygous for cleft chin, and the other parent does not have a cleft chin.

Which best summarizes the results of Mendel’s pea plant experiments?