- Which of the following was NOT one of Gregor Mendel’s principles of heredity?
a. principle of discrete traits
b. principle of random segregation
c. principle of canalization
d. principle of dominance-recessiveness
- _ are segments of DNA molecules that are the functional units of heredity and come in pairs.
- Alternative forms of single genes are called
b. polar bodies.
- Albinism is a recessive condition in which people lack pigment that gives skin its color. If a child has albinism, then we know that
a. the child has one allele for albinism and one allele for normal skin color.
b. the child has two alleles for albinism.
c. the child is missing a skin color allele from its pair.
d. one parent had two alleles for albinism and the other parent had two alleles for normal skin color.
- An organism’s genetic makeup is its , while its physical appearance is called its _.
a. genotype; heritability
b. phenotype; genotype
c. heritability; phenotype
d. genotype; phenotype
- A_________ allele is one that masks the influence of other alleles and is therefore expressed.
- A_________ allele is one that is not expressed unless both alleles in a pair are present.
- A_________ allele is one that masks the influence of other alleles and is therefore expressed, while a _ allele is not expressed unless both alleles in a pair are present. a. genotypic; phenotypic
b. phenotypic; genotypic
c. recessive; dominant
d. dominant; recessive
- If albinism is a recessive condition like Mendel’s green seeds, then if each parent has one normal pigment allele and one allele for albinism, the probability ratio of normal pigmentation to albinism would be
- Sara has phenylketonuria, but neither of her parents have the condition. Thus, Sara must have allele(s) for phenylketonuria, and her parents must each have allele(s) for phenylketonuria.
a. 1; 0
b. 1; 1
c. 2; 0