It’s B the other person put D but that’s the cell wall or cell membrane
HOPE THIS HELPS !
Answer:
the umbilical cord is considered both the physical and emotional attachment between mother and fetus.
Explanation:
this structure allows for the transfer of oxygen and nutrients from the maternal circulation into fetal circulation while simultaneously removing waste products from fetal circulation to be eliminated maternally.
Diffusion. It follows the concentration gradient, moving from high to low.
<span>enzymes are resuable as they are biologically catalyst which speeds up the rate of a reaction without being chemically changed themselves. However, if the enzyme is to be denatured under unfavourable conditions (extreme temperatures, extreme pH), the enzymes may not be reusable once denatured.</span>
