20.4 21.3 are the correct answers
If the sperm cell fertilises the ovum, and implantation does not occur, then the corpus luteum degenerates and it turns into corpus albicans, stopping progesterone secretion. If fertilisation occurs and implantation also, the syncytiotrophoblast, the "root part" of the blastocyst (one of the early structures originated from the zygote), produces a hormone that is called <span>human chorionic gonadotropin (hCG). The hCG is what makes the corpus luteum keep secreting progesterone and maintain itself. The progesterone will then help keep the endometrium and, therefore, allow the development of the embryo to happen.</span>
Answer:
Having a similar dna makeup as one animal but our features and genetic makeup different than that one animal.
Explanation:
There is unity in having the same dna as one animal but diversity in our features
The difference is very small, if it exists at all. Please Mark Brainliest!
