1 Navy pilots move a lot, both during and after training. During your 2 to 2.5 years of flight school, you can expect to move 3 or 4 times. While you will be home during school, you will work odd and often inconsistent hours.  Your work obligations are dependent on your country's needs.
], respiration [respiration: Chemical change that takes place inside living cells, which uses glucose and oxygen to produce the energy organisms need to live. Carbon dioxide is a by-product of respiration ] and combustioncombustion: Combustion is the process of burning by fire.. Green plants remove carbon dioxide from the atmosphere by photosynthesis. Living organisms - including all plants and animals - release energy from their food using respiration. Respiration and combustion - burning - both release carbon dioxide into the atmosphere.
Notice that photosynthesis and respiration are essentially the opposite of one another. Photosynthesis removes CO2 from the atmosphere and replaces it with O2. Respiration takes O2 from the atmosphere and replaces it with CO2. However, these processes are not in balance.