Answer:
Arteries
Explanation:
There are three main types of blood vessels: veins, arteries, and capillaries. Arteries are the blood vessels that carry the oxygenated blood from the heart to various body parts. Veins pick the deoxygenated blood and deliver it to the heart to be oxygenated.
Arteries are the blood vessels with thick walls and no valves. Blood is pumped with higher pressure from the heart into arteries. The pulmonary artery is the only exception that carries deoxygenated blood from the right ventricle to the lungs for oxygenation.
Increasing melanin production.
Good luck! (:
~ Jasmine
Answer:
it happens when 2 organisms jelp each other beneficial.
Explanation:
eg:algae and leguminous plants.the algae live on the roots and take in the nitrogen from the soil,which the plant cannot do and needs for growth.it takes in the nitrogen and pases it to the roots and even make the soil loose for the roots to move and they get a living space(algae on the roots).
