Answer: Option A.
Explanation:
Secretory phase in menstrual cycle is the second half after ovulation.
During the secretory phase, the corpus luteum secretes high level of progesterone that prepares the endometrium wall for implantation of an embryo and if fertilization does not take place, it results in menstrual flow.
Hence, the high level of progesterone takes place during secretory phase of menstrual cycle.
Answer:
The correct answer is A.
During the secretory phase of the menstrual cycle progesterone levels are at their highest.
Explanation:
The luteal phase, also called the secretory or postovulatory phase, is the one that begins just after ovulation and lasts until the end of the menstrual cycle, that is, until there is menstrual bleeding again. The broken follicle turns into a yellowish body called the yellow body or corpus luteum. This body is responsible for producing estrogens and progesterone, the two hormones that will act on the endometrium. At this time, progesterone is now responsible for modifying cervical mucus so that it becomes impenetrable by sperm again, that is, during this phase, the endometrium prepares to support a pregnancy or disintegrate at menstruation. The increase in progesterone levels causes the endometrium to stop thickening and begin to prepare for the potential implantation of a fertilized egg.
