Genes and Alleles

Front

A segment of DNA that codes for a trait

Back

gene

Front

When an organism has two different alleles, it is called

Back

heterozygous

Front

These types of alleles are only expressed if the organism has two copies

Back

recessive

Front

This type of allele is expressed whether there are one or two copies present.

Back

dominant

Front

The genotype gg is best described as

Back

homozygous

Front

The physical expression of a trait is known as

Back

phenotype

Front

The genetic makeup of an organism is referred to as its

Back

genotype

Front

An allele that masks the effect of another allele is called

Back

dominant

Front

An allele that is masked by a dominant allele is called

Back

recessive

Front

If an organism has two identical alleles for a trait, it is said to be

Back

homozygous