Biology - Genetics

Which of the following correctly identifies a homozygous dominant genotype?

• tt

• Tt

• TT

• tall

In a certain species of animal, black fur (B) is dominant over tan fur (b).  If two heterozygous parents were crossed what percentage of the offspring would be Homozygous dominant?

• 0%
• 25%
• 50%
• 75%

Snapdragon flowers display incomplete dominance. Red is dominant to white, but heterozygotes have pink flowers. If a red snapdragon and a pink snapdragon were crossed, what percentage of the offspring would be Red?

• 0%

• 25%

• 50%

• 75%

• 100%

observable characteristics of the individual; the way the genotype is expressed

• alleles

• Nucleotides

• phenotypes

• diploid

In chickens, feather color is codominant. If a black chicken BB is mated with one that is black and white (BW) what are the chances of having a chicken that is black and white?

• 0%

• 25%

• 50%

• 75%

• 100%

different forms of the same gene located at the same point of homologous chromosomes

• alleles

• Nucleotides

• phenotypes

• chromosomes

Blood type exhibits multiple alleles and codominance. There are 4 blood types: A, B, AB, and O. If a heterozygous type B man and a type AB woman want to have a child, what are the chances that they will have a type B child?

• 0%

• 25%

• 50%

• 75%

• 100%

Sickle cell anemia is an autosomal recessive disorder that affects the ability of blood to clot. If a woman with sickle cell anemia has children with a man who is heterozygous for sickle cell, what are the chances their child will have the disorder?

• 0%

• 25%

• 50%

• 75%

• 100%

trait shown by lower case letters

• dominant
• recessive
• sex-linked
• codominant

A man who is homozygous for type A blood marries a woman who is heterozygous for type B. What are the possible genotypes of their children?

• AA, AB, AO

• BB, AB

• AB, AO

• Ab