In a genetic cross, where the male parent is heterozygous for curly hair (hh) and the female parent is homozygous for straight hair (hh), the offspring would
a. all have straight hair
b. all have curly hair
c. half would have straight hair and half curly hair
d. a random mixture of straight and curly haired offspring, with more having curly hair.

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.