10. What statement is true about embryonic stem cells and adult stem cells? A. Adult stem cells are pluripotent and embryonic stem cells are multipotent.
B. Only embryonic stem cells can be used for research; adult stem cells do not grow in laboratories.
C. Adult stem cells can produce only new blood cells, while embryonic cells can produce all cell
types.
D. Embryonic stem cells can produce every type of cell in the body; adult stem cells can only
produce the type of cells from the tissue they came from.

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.