Secretion of human chorionic gonadotropin [HCG] only occur during pregnancy in the placenta. The concentration of this hormone increase rapidly during the first three months of pregnancy; the amount in the blood stream doubles every two to three days as the development of the placenta and embryo progress. The hormone reaches its maximum concentration peak around the sixth week of pregnancy and after this, its concentration decline.
Fossil Fuels, Coal, and Gold
Travel thru the other cells
An organelle is a specialized structure inside Eukaryotic cells.
<span>Different pressure levels
Hope this helps and please award brainly :)
</span>
