Carbon dioxide in respiration

Potassium superoxide (KO2) is used in some self-containing breathing equipment by firefighters. It reacts with carbon dioxide in respired (exhaled) air to form potassium carbonate and oxygen gas. (a) Write an equation for the reaction, (b) What is the oxidation number of oxygen in the O " ion (c) How many liters of respired air can react with 7.00 g of KO2 if each liter of respired air contains 0.063 g of CO2 ... 

The excessive amount of bicarbonate in the blood means that blood has a much greater capacity to neutralize acids. Many acids accumulate in the blood during strenuous activity, for example lactic acid. Excretion of bicarbonate through the kidneys and the removal of carbon dioxide through respiration also regulate the carbonic acid/ bicarbonate blood buffer. 

Photosynthesis and respiration help to maintain the concentrations of oxygen and carbon dioxide in the atmosphere. Respiration is the process by which carbohydrates (most commonly glucose) are broken down for the release of energy needed for life processes. Photosynthesis uses carbon dioxide and produces oxygen. Respiration does the opposite—it uses oxygen and produces carbon dioxide. Plants and algae carry on photosynthesis, while animals carry... 

Alveoli Tiny air sacs of die lungs at the end of a bronchiole, through which gas exchange takes place by which the blood takes in oxygen and gives up its carbon dioxide in the process of respiration. 

The human body is a remarkable machine. It relies on a variety of safeguards to keep blood pH constant. Our blood constitutes a buffer system — meaning, it has components that can react with excess base or excess acid. Carbon dioxide, which is produced by the metabolism of food, dissolves in blood to produce carbonic acid, and carbonic acid can neutralize any excess base. The bicarbonate ion, also present in blood, will promptly take care of any surplus acid. The level of carbon dioxide in the blood adjusts to a body s rate of respiration. If blood pH drops — which actually means that the blood has... 

The greater the amount of carbon dioxide in soil, the more hydronium ions and so the lower the pH. Soil that has a low pH is referred to as sour. (Recall from Chapter 10 that many acidic foods, such as lemon, are characteristically sour.) Two main sources of soil carbon dioxide are humus and plant roots. The humus releases carbon dioxide as it decays, and plant roots release carbon dioxide as a product of cellular respiration. A healthy soil may have enough carbon dioxide released from these processes to give a pH range from about 4 to 7- If the soil becomes too acidic, a weak base, such as calcium carbonate (known as lime or limestone), can be added. 

As a general rule, the respiration of individual cells decreases as the concentration of carbon dioxide in the medium increases. Fish show a lessened capacity to extract oxygen from their environment with increasing amounts of carbon dioxide present. On the other hand, many invertebrates show marked increases in respiratory rate (or ventilation) with increased amounts of the gas In their surroundings. 

Algae seem to offer better opportunities for study than land plants because of their simpler structure and intimate thermal contact with a large excess of water. The matter of respiration is troublesome, for, in the dark, the living cells consume oxygen and liberate carbon dioxide in direct opposition to the photosynthetic reaction. It has been assumed that respiration is the same in the light as in the dark, but this assumption is of doubtful validity. Further investigation of respiration is necessary. 

Lavoisier is credited with determining that water results from the combination of the elements oxygen and hydrogen. He also studied respiration in animals and plants and defined the role of oxygen in the process of respiration. He determined that humans take in oxygen and give off carbon dioxide during respiration. 

Finally, after all of the sulfate is consumed, organic material can be fermented into methane and carbon dioxide in the process of methanogenesis. Fermentative reactions, of which there are many examples in the environment, differ from respiration in that they do not change the average oxidation state of carbon. The reaction for methanogenesis is... 

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