Which of the following statements about quitting smoking is true? a. Carbon monoxide levels stabilize in a few minutes
b. Cilia in the airways never recover function
c. The risk of heart disease falls by 50% after one year

Anita thinks that she has heterozygous alleles for red hair.if she is correct, which of these diagrams best illustrates anitas alleles pf red hair

A(n) is a molecule influences the way that a molecule reacts.

During crossing-over, a. genetic material is exchanged between nonsister chromatids, resulting in new combinations of alleles. b. nonsister chromatids from each homologous chromosome of a tetrad are exchanged, resulting in new combinations of alleles. c. one homologous chromosome of a tetrad is exchanged with another tetrad, resulting in new combinations of alleles. d. sister chromatids from each homologous chromosome of a tetrad are exchanged, resulting in new combinations of alleles. e. genetic material is exchanged between sister chromatids, resulting in new combinations of alleles.