It is not just the muscle cells that respire. All cells in the body need oxygen for respiration and all cells need to get rid of the carbon dioxide that they produce. In the lungs oxygen is taken from air into the blood and the blood transports the oxygen to the cells in all tissues of the body.As the muscles use the oxygen up,carbon dioxide is produced and absorbed into the blood. And this de-oxygenated blood is pumped back to the heart then on to the lungs. The lungs get rid of this carbon dioxide, and breathe in more oxygen.
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Exothermic reactions occur outside of the object, while endothermic occur on the inside.
Answer and Explanation:
The number of mitochondria in an insect's wing will be more than in the insect body. Wings are used for flight and therefore the energy demand is higher. Greater number of mitochondria in the wings increases the energy supply to the cells.
Answer:
Kitten
Cactus
Mushrooms
Bacteria
so all but Rock
Because only living things have cells