Species adapt to their environment using mutations to give them characteristics that better fit their environment over generations
Answer:
Oxygen
Explanation:
The heart, like any organ, requires blood for oxygen and other nutrients so it can do its work. The heart does not gather oxygen or nutrients from the blood flowing inside it. Instead, it receives blood from coronary arteries that eventually carry blood into the heart muscle.
The answer to this would be reactants.
I think is rain don’t know but good luck and have a nice day
