Answer:
1.5 billion years ago
Explanation:
Protists are a collection formed up of protozoa, unicellular algae, and fungus forms. We will focus on the being part of this society: the protozoa (proto = first, zoa = beings). Protozoa are the earliest discovered collection of heterotrophic living that utilize and modify complicated meal particles into power. Although protozoans are only made up of a single cell, these organisms control to perform all the necessary responsibilities of life. The protozoa are split into four principal associations: the ciliates, the flagellates, the heliozoans, and the amoebas.
Human chorionic gonadotropin (hCG) is secrete by the embryo early in pregnancy to keep the corpus luteum for dying. This positive feedback will maintain the corpus luteum, which secretes Progesterone and Estrogens throughout pregnancy, in order to keep the endometrium well to nourish the embryo/fetus.
B
The other problems are not as easily solved; whereas, data collection over long periods of time is possible and was already done in the past, eg temperature and weather patterns. Therefore, this is the easiest limitation to overcome.
<span>Spermatozoa are the mature male gametes in many sexually reproducing organisms. Thus, spermatogenesis is the male version of gametogenesis, of which the female equivalent is oogenesis. In mammals it occurs in the seminiferous tubules of the male testes in a stepwise fashion.</span>
Hypertrophy or hypertrophic. Hope that answered your question :)