Active muscles demand huge amounts of oxygen, and the circulatory system works hard to provide it. Blood carries oxygen to the muscles. When the body is at rest, blood carries nutrients to the muscles so that they can repair and rebuild themselves. Blood also carries away the waste products that hard-working muscles produce, back out through the lungs to be filtered.
so they Circulatory system xx muscular system :)
The two stages of photosynthesis: Photosynthesis takes place in two stages: light-dependent reactions and the Calvin cycle (light-independent reactions). Light-dependent reactions, which take place in the thylakoid membrane, use light energy to make ATP and NADPH.
<span>In the reaction that builds a fat, hydroxil groups react with carboxyl groups. Both hydroxil and carboxyl are </span><span>functional </span>groups<span> in biological molecules. The h</span>ydroxil group is group of atoms found in organic compounds, expressed with the formula OH. The carboxyl group are found in acids.