DDE Genetics Unit Review

What do you call an allele that expresses its trait when there is only 1 copy?

• recessive

• hidden

• strong

• dominant

What do you call an organism that has two identical copies of an allele?

• homozygous

• heterozygous

• recessive

• dominant

Name this genotype: Tt

• homozygous dominant

• heterozygous

• homozygous recessive

Name this genotype: YY

• homozygous dominant

• heterozygous

• homozygous recessive

Name this genotype: ii

• homozygous dominant

• heterozygous

• homozygous recessive

Red flowers (R) are dominant to yellow flowers (r). What is the genotype of this flower?

• RR

• Rr

• rr

Red flowers (R) are dominant to yellow flowers (r). If two heterozygous flowers breed, what percentage of the offspring will be homozygous dominant?

• 25%

• 50%

• 75%

• 100%

Red flowers (R) are dominant to yellow flowers (r). If two heterozygous flowers breed, what percentage of the offspring will be red?

• 25%

• 50%

• 75%

• 100%

The observable trait resulting from an organism's DNA is called its _________.

• genotype

• phenotype

• trait

• allele

The combination of alleles that controls the organism's traits is called their _____________.

• genotype

• phenotype

• allele

• trait