Answer:
All life respires, or breathes. Respiration in mammals is similar to respiration in other air-breathing animals. Respiration extracts oxygen from the air, which is then used by cells. Respiration also carries waste carbon dioxide away from the cells. Although respiration depends on other systems, like the circulatory system, to take oxygen and carbon dioxide to and from cells, the respiratory system has the primary responsibility of bringing oxygen in to a mammal's body and sending carbon dioxide into the atmosphere.
Explanation:
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Lactic acid fermentation and alcoholic fermentation
There is external and internal so I'll list th external. The most important is skin then mucus, sweat or secretion, hair, nails and tears which are all part of the integumentary. Some internal defenses are white blood cells and T cells.