You breathe in oxygen, you exhale carbon dioxide.
It is safe but you shouldn't breathe in carbon dioxide all the time.
Answer:
Transport proteins allows only enzymes to pass through the membrane
Explanation:
Answer:
Sunlight is important in my life because you need it if you have a plant and you want to take care of the plant.Postive effects of sunlight is Sun water and needing health
C. They unwinds the two strand of DNA.
Answer:
C
Explanation:
the first 2 choices aren't even systems at all, and D is specifically talking about the water and not mentioning animals/plants at all.
hope this helps!
