Answer:B
Explanation:bc all of the other ones was equal together and the concentration gradient could not spread them
The 1st one is plasma membrane because it is the outside
the 2nd one is the cytoplasm because it is the middle part
the 3rd one is the nucleus because it is the center
p.s. I need brainliest i'm gonna lose a rank because i havent got enough brainliests
Answer:
blood
Explanation:
I looked it up and it said arteries and veins. I also took anatomy and physiology
