Answer:
substances can move from areas of low concentration to areas of high concentration
Explanation:
usually substances move across their concentration gradient which is from high concentration to low concentration. Active transport can allow substances to move against their concentration gradient.
يعينك على خير ان شاءالله يارب وياك يارب وياك يارب وياك يارب وياك يارب وياك يارب وياك يارب وياك يارب وياك يارب وياك يارب وياك يارب وياك يارب وياك يارب وياك
Answer:
Model B
Explanation:
It let's more fluids flow through unlike Model A
