15) Horseshoe crabs, genetically related to scorpions and spiders, are capable of only one type of
fertilization. Female horseshoe crabs dig a shallow hole near the ocean shoreline that can fill
with water. They then lay their eggs in that hole, and male horseshoe crabs mount the females
and deposit their sperm over the eggs. This is an example of
A) external fertilization without copulation.
B) external fertilization with copulation.
C) internal fertilization without copulation.
D) internal fertilization with copulation.
16) Why might scientists want to figure out how to change sexually reproducing plants that are
in high demand in agriculture into asexually reproducing plants?
A) Farmers would be able to harvest asexually producing plants in a more efficient manner
because asexual reproduction has lower energy costs than sexual reproduction.
B) Farmers who constantly have to buy new seeds for high-demand plants would have their seed
costs cut dramatically.
C) High-demand plants, such as beans and corn, will have higher taste quality in asexually
reproducing plants.
D) Asexually reproducing plants require less water and fertilizer than sexually reproducing
plants.
17) Among nonmammalian vertebrates, the cloaca is an anatomical structure that functions as a
A) specialized sperm-transfer device produced only by males.
B) shared pathway for the digestive, excretory, and reproductive systems.
C) region bordered by the labia minora and clitoris in females.
D) source of nutrients for developing sperm in the testes.
E) gland that secretes mucus to lubricate the vaginal opening.