Answer:
The portion of the uterus that changes during the uterine cycle is the :
e) functional layer of endometrium
Step-by-step explanation:
In every uterine or menstrual cycle when pregnancy did not occur, the uterus sloughs off its thin and superficial functional layer; this is known as menstruation.
The basal layer or stratum basali of endometrium is responsible for the regeneration of the functional layer, every cycle after the menstruation period.