Biology Unit 2 Genetics Test

Blue eyes is a recessive trait. Gwen has blue eyes but both of her parents have brown eyes. Which of the following statements explains this?

• Gwen's parents are both homozygous dominant.

• Gwen's parents are both heterozygous.

• Gwen's parents are both homozygous recessive.

• Gwen's mother was homozygous dominant and her father was homozygous recessive.

Cystic fibrosis (CF) is a recessive trait that causes severe damage to the lungs, digestive system and other organs of the body.

Jack and Diane (first generation of the diagram) had 5 children. Which of the following represents the phenotypes of these children?

• 3 are CF carriers, 1 has CF, and 1 is neither a carrier nor has CF

• 3 are CF carriers, 1 has CF, and 3 are neither a carrier nor have CF

• 0 are carriers, 4 have CF, and 1 is neither a carrier nor has CF

• 1 is a carrier, 1 has CF, and 3 are neither a carrier nor have CF

Cystic fibrosis (CF) is a recessive trait that causes severe damage to the lungs, digestive system and other organs of the body.

What determines whether a person has cystic fibrosis or not?

• They have two recessive alleles.

• They have two dominant alleles.

• They have one dominant allele and one recessive allele.

• They have more than two alleles.

Achondroplasia is a dominant genetic condition that results in dwarfism. In those with the condition, the arms and legs are short, while the torso is typically of normal length. The pedigree below shows the inheritance of achondroplasia within a family.

What is the genotype of the male labeled A?

• Homozygous dominant

• Homozygous recessive

• Heterozygous

• Impossible to determine

Hemoglobin is a protein that binds oxygen to red blood cells. Below is a section of the normal hemoglobin gene and two different possible mutations.

Normal DNA Sequence: G G A C T C C T C

Mutation Sequence #1: G G A C A C C T C

Mutation Sequence #2: G G A T T A C T C

Which of the mutations would change the hemoglobin protein the most?

• Mutation 1 because it changes the structure of the protein

• Mutation 2 because it changes the structure of the protein

• Mutation 2 because it changes more of the nucleotide bases

• Both mutations will have an equal effect on the protein

Hemoglobin is a protein that binds oxygen to red blood cells. Below is a section of the normal hemoglobin gene and two different possible mutations.

Normal DNA Sequence: G G A C T C C T C

Mutation Sequence #1: G G A C A C C T C

Mutation Sequence #2: G G A T T A C T C

Which of the following events would cause a person to have a mutation in the hemoglobin gene in every cell of their body?

• The person inhales harmful chemicals in cigarette smoke as an adult.

• A DNA replication error occurred before meiosis to make the egg or the sperm they received from their parents.

• Radiation from the sun damages the DNA in their skin cells when they got a sunburn as a teenager.

• An error in DNA replication before mitosis when the person growing as a small child.

What is the function of antibodies within the immune system?

• Antibodies kill off any antigen that enters the body.

• Antibodies are only made when you are given a vaccination for specific antigens.

• Antibodies bind to specific antigens to flag for destruction.

• Antibodies are part of an external defense mechanism.

Some examples of external defenses are...

• Skin

• Mucus

• Inflammation

• Saliva

• Sweat

Pathogens are...

• Foreign substances that attack the body.

• White blood cells that attack foreign substances that enter the body.

• A type of internal defense mechanism in the immune system.

• Proteins that cause disease.

Insertion, deletion, and substitution are all examples of a change in a genetic sequence which is also referred to as (a)

• Gene

• Amino Acid

• Ribose

• Mutation