Answer:
The correct answer is A.
Explanation:
Diffusion is the net movement of a substance from a region of higher concentration to a region of lower concentration. The difference in concentration between two environments creates a concentration gradient which is what drives diffusion. Therefore, this movement does not require aid such as extra energy molecules for active transport or integral membrane proteins for directed movement, hence the answer is not B nor C. If the cell is in equilibrium with its environment, it means that the concentration of substances inside the cell is equal to the concentration outside the cell, and any movement that takes place will be random movement of substances across the plasma memberane. Movement in the cell will not cease as the cell is still active. Therefore, the answer cannot be D either.
Answer:During pregnancy, red blood cells from the unborn baby can cross into the mother's blood through the placenta. If the mother is Rh-negative, her immune system treats Rh-positive fetal cells as if they were a foreign substance. The mother's body makes antibodies against the fetal blood cells
Explanation:
It results in change of the phase temperature and heat