Genetics quiz

Dihybrid crosses examine ____ trait(s) at a time.

• one
• two
• multiple
• no

A ____ is the genes you have for a trait, while the ____ is the physical result of those genes.

• phenotype, genotype
• genotype, phenotype
• monohybrid, dihybrid
• genetics, health

When the heterozygous condition results in the organism having blended traits ( like red and white make pink), we call that _____.

• codominance
• incomplete dominance
• dihybrid
• monohybrid

When the heterozygous condition results in the organism having both traits equally expressed ( like black and white genes give a speckled chicken), we call that ____.

• codominance
• incomplete dominance
• dihybrid
• monohybrid

Codominance and incomplete dominance are examples of exceptions to Mendel's rules.

• true
• False

Codominance. Cross a homozygous black chicken (B) with a homozygous white chicken (W). Give the phenotype.

• 100% black chickens
• 100% white chickens
• 100% speckled (both black and white)
• 50% speckled and 50% white chickens

Incomplete dominance. Cross two pink flowered (RW) plants. What is the phenotype of the offspring?

• 1/4 red, 2/4 pink, 1/4 white
• 2/4 red, 2/4 white
• 100% red
• 2/4 pink, 2/4 white

Human blood typing is an example of a codominant trait.

• true
• False

Dihybrid problem R= round r =wrinkled P = purple p = white A heterozygous round seed and heterozygous purple flowered plant is crossed with a homozygous round and homozygous purple plant. What are the phenotypes that result from this?

• 100% round and purple
• 50% round and purple , 50% wrinkled and white
• ¼ round and purple, ¼ round and white, ¼ wrinkled and purple, 1/4 wrinkled and white

Dihybrid problem R= round r = wrinkled P = purple p = white A homozygous round seed plant with homozygous purple flowers is crossed with a homozygous wrinkled seed plant with white flowers. What is the genotype that results?

• ¼ RrPp, ¼ Rrpp,¼ rrPp, ¼ rrpp
• 100% RrPp
• ¼ RRPP, ¼ RRPp, ¼ RrPP, ¼ RrPp