Genetics Quiz

Why is it difficult to study the genetics of humans?

Circle the letter of each sentence that is true about human blood group genes.

• The Rh blood group is determined by a single gene.

• The negative allele (Rh-) is the dominant allele.

• All of the alleles for the ABO blood group gene are codominant.

• Individuals with type O blood are homozygous for the i allele (ii) and produce no antigen on the surface of red blood cells.

Is the following sentence true or false? Many human genes have become known through the study of genetic disorders.

• True

• False

What is the normal function of the protein that is affected in cystic fibrosis?

A change in just one DNA base for the gene that codes for the protein Hemoglobin causes sickle-shaped red blood cells.

What is the advantage of being heterozygous for the sickle cell allele?

What makes an allele dominant, recessive, or codominant?