[Campbell Biology P.793] Which of the following accurately describes a difference in reprodu... | Practice Question

Which of the following accurately describes a difference in reproductive biology between eutherians and marsupials, according to the text?

  • A: Eutherian placentas are simpler than marsupial placentas, leading to shorter pregnancies.
  • B: Marsupials complete embryonic development within the uterus, while eutherians do so in a pouch.
  • C: Eutherians have a longer pregnancy, and their young complete embryonic development within the uterus, supported by a complex placenta.
  • D: The association between mother and young is more intimate and long-lasting in marsupials due to their complex placenta.

Explanation

The text explains: 'Eutherians are commonly called placental mammals because their placentas are more complex than those of marsupials. Eutherians have a longer pregnancy than marsupials. Young eutherians complete their embryonic development within the uterus, joined to their mother by the placenta. The eutherian placenta provides an intimate and long-lasting association between the mother and her developing young.'