17-18 Genetics and Inheritance

A farmer who raises vegetables wants to cross two types of corn plants. One type is a heterozygous plant with red kernels (Rr) and the other is a homozygous plant with white kernels (rr).

• The plants will produce offspring with all red kernels.

• The plants will produce offspring with all white kernels.

• The plants will produce some offspring with red kernels and others with white kernels.

• The plants will produce offspring with all pink kernels.

What did Mendel conclude about inherited traits?

• Alleles for eye color and hair color are inherited together.

• Multiple factors control each inherited trait.

• A parent that possesses two alleles for a trait will pass both on to its offspring.

• A parent that possesses two alleles for a trait will only pass on one to its offspring.

A heterozygous rabbit has long ears. What can we conclude?

• Short ears is the recessive trait.

• Long ears is the recessive trait.

• The rabbit has two long ear alleles.

• The rabbit has two short ear alleles.

A plant breeder crosses two homozygous pea plants, one having dominant alleles for purple flowers (PP) and another having recessive alleles for white flowers (pp). Which of these BEST describes the phenotype inherited by the offspring?

• The offspring have purple flowers because they inherited both a dominant and recessive allele, but only the dominant is expressed.

• The offspring have white flowers because a mutation occurred after the breeding process.

• The offspring have white flowers because they inherited recessive alleles from both parents.

• The offspring have purple flowers because they only inherited the dominant alleles from both parents.

Curly hair is recessive, and straight hair is dominant. A woman with curly hair marries a man who is homozygous and has straight hair. What is the possibility that their offspring will have curly hair?

• 25%

• 50%

• 100%

• 0%

• 75%

A model that is used to show possible outcomes of cross-breeding is a

• ratio.

• genetics.

• breed.

• Punnett square.

A genetic factor that is blocked another genetic factor and is not expressed is

• Homologous chromosome

• Allele

• Recessive

• Dominant

A genetic factor that blocks another genetic factor and is expressed is

• Homologous chromosome

• Allele

• Recessive

• Dominant

A different form of a gene is called a(n)

• Homologous chromosome

• Allele

• Recessive

• Dominan

With blonde hair as the dominant allele and brown hair as recessive, what will the phenotype of the offspring shown in the Punnett square be?

• All four will have brown hair.

• All four will have blonde hair.

• Two out of four will have brown hair.

• Two out of four will have blonde hair.