The blastocyst implants in the uterus on about the ________ day of the 28-day menstrual cycle.At this time,the endometrium is ________ and progesterone levels are ________.
A)21st;thick and secretory;high
B)28th;thick and secretory;low
C)14th;thick and secretory;low
D)28th;thin and proliferating;high
E)21st;thin and proliferating;low

Question

Quizplus · Accepted Answer

The blastocyst implants in the uterus on about the 21st day of the 28-day menstrual cycle. At this time, the endometrium is thick and secretory, indicating that the body is preparing for pregnancy. Progesterone levels are high to maintain the uterine lining and support a potential pregnancy.

The Blastocyst Implants in the Uterus on About the ________