[Campbell Biology P.1091] Which of the following statements accurately describes a key differ... | Practice Question

Which of the following statements accurately describes a key difference between menstrual and estrous cycles in mammals?

  • A: All mammals exhibit menstrual cycles.
  • B: The endometrial lining is shed during menstrual cycles but reabsorbed during estrous cycles.
  • C: Estrous cycles are generally less frequent than menstrual cycles.
  • D: Ovulation typically occurs after the endometrium thickens in menstrual cycles, but before in estrous cycles.

Explanation

A key distinction is that in menstrual cycles, if pregnancy does not occur, the endometrial lining is shed menstruation . In contrast, during estrous cycles, the endometrial lining is typically reabsorbed by the uterus if conception does not happen.