[Campbell Biology P.1073] Which of the following statements accurately highlights a key diffe... | Practice Question

Which of the following statements accurately highlights a key difference between the reproductive systems of most mammals and those of many nonmammalian vertebrates, as described in the text?

  • A: Most mammals typically have a cloaca for digestive, excretory, and reproductive openings, whereas nonmammalian vertebrates do not.
  • B: Nonmammalian vertebrates often have a cloaca, while most mammals have separate openings for the digestive, excretory, and reproductive systems.
  • C: Sperm storage in spermathecae is common in mammals but rare in nonmammalian vertebrates.
  • D: Mammals exhibit a divided uterus, while nonmammalian vertebrates always have a single uterine structure.

Explanation

The text explicitly states: 'In many nonmammalian vertebrates, the digestive, excretory, and reproductive systems have a common opening to the outside, the cloaca... In contrast, mammals generally lack a cloaca and have a separate opening for the digestive tract. In addition, most female mammals have separate openings for the excretory and reproductive systems.' This directly supports option B.