I believe it is a - Detailed instructions for operator hygiene
The word “psychology” comes from the ancient Greek roots psyche, which means “mind”, and logos, meaning “knowledge or study.”
Explanation:
During implantation, the trophoblast differentiates into two distinct layers: the inner cytotrophoblast, and the outer syncytiotrophoblast.
Answer:
D) four.
Explanation:
The two atria hold the blood that circulates away from the heart. The heart has four one-way valves, which open and close with each heartbeat. The tricuspid valve and the mitral valve are located between the atria and allow the blood to flow from the atria to the ventricles. Also you don't have to but mind marking Brainliest?
