I think this answer would be C or D. i know it wasnt much hope i helped!
C) It is thin tissue that lines the alveoli
Your veins and arteries allow blood to flow to and from the heart to every part over your body. This is what keeps us alive.
Hope this helps! If there is anything wrong, feel free to tell me.
Have a nice day!
Answer -
(Eukaryotes)
Nucleus (N)
The nucleus function is the control and command center.
Reason - This is too obvious. I picked eukaryotes because it's basic cells for animilia. The nucleus is simple because it's obviously also a command and control for all common cells.
Answer: ONLY CERTAIN SUBSTANCES CAN PASS THROUGH IT
Explanation:
1 only gases and water can pass through it.
2 substances need permission to pass through it.
3 only certain substances can pass through it.
4 substances need carrier molecules to pass through it.
5 ATP is always needed to move molecules across the plasma membrane.