Genetics Review

Front

What does heterozygous mean?

Back

When an organism has two different alleles for a trait (ex. Tt)

Front

When an offspring has the recessive form of a trait, what does that mean about the parents?

Back

One parent has 2 recessive alleles and the other parent has 1 dominant and 1 recessive allele.

Front

Having 2 of the same type of allele is also called __________.

Back

Purebred

Front

What is the genetic makeup of an organism?

Back

Genotype

Front

What are the different variations of a gene?

Back

Allele

Front

What does homozygous mean?

Back

When an organism has two identical alleles for a trait (ex. RR or rr).

Front

What is a phenotype?

Back

The observable physical or biochemical characteristics of an organism, determined by both genetic makeup and environmental influences.

Front

What is a dominant allele?

Back

An allele that expresses its trait even when only one copy is present (ex. R in Rr).

Front

What is a recessive allele?

Back

An allele that only expresses its trait when two copies are present (ex. rr).

Front

What is a Punnett square?

Back

A diagram used to predict the outcome of a genetic cross by showing the possible combinations of alleles.