The heart, it pumps blood and oxygen all over your body
Answer:
The exchange of biological material between tissues and blood vessels.
Explanation:
Capillaries are extensions of blood vessels but are much thinner in diameter. They are mostly found in tissue that is highly metabolic like the kidneys and liver which require high perfusion and exchange rate of metabolic molecules between tissue and blood.
An acid because if its less than 5 its an acid
