I think the answer is C sorry if i got i wrong.
<span>Fossil
fuels represent carbon storage areas. Carbon that is locked in these
fossil fuels does not cycle through the Earth. When humans burn fossil
fuels, the stored carbon is released into the atmosphere as carbon
dioxide. The carbon is then free to cycle through the Earth and can
upset the natural balance of the carbon available, changing the way that
processes occur on Earth.</span>
The base of an adenine molecule is made of ribose sugar molecules
Sample A most likely came from the left ventricle, as this is the portion of the heart that receives freshly oxygenated blood to be pumped to different parts of the body. Oxygenated blood is blood that has had oxygen bounded to it by hemoglobin (a pigment made of iron found in red blood cells). The oxidation of this blood by the iron in the hemoglobin gives it the RBC bright red look. This blood containing the bright RBCs in transported to the left ventricle from the lung, after which it is spread throughout the body. Hence, in normal conditions of the heart, the Sample A most likely came from the left ventricle.
active transport. The movement of ions or molecules across a cell membrane in the direction opposite that of diffusion, that is, from an area of lower concentration to one of higher concentration. Active transport requires the assistance of a type of protein called a carrier protein, using energy supplied by ATP.