Your body

Equally, if your body requires more oxygen than the available oxygen in the atmosphere, then you would be asphyxiated. There must be more oxygen available in the air than the oxygen you consume. 

Convective heat transfer occurs when a fluid (gas or liquid) is in contact with a body at a different temperature. As a simple example, consider that you are swimming in water at 21°C (70°F), you observe that your body feels cooler than it would if you were in still air at 21°C (70°F). Also, you have observed that you feel cooler in your automobile when the air-conditioner vent is blowing directly at you than when the air stream is directed away from you. Both ot these observations are directly related to convective heat transfer, and we might hypothesize that the rate of energy loss from our body due to this mode of heat transfer is dependent on not only the temperature difference but also the typie of surrounding fluid and the velocity of the fluid. We can thus define the unit heat transfer for convection, q/A, as follows ... 

The total number of calories a person needs each day is the sum of the basal requirement plus the energy used for physical activities, as shown in Table 29.1. A relatively inactive person needs about 30% above basal requirements per day, a lightly active person needs about 50% above basal, and a very active person such as an athlete or construction worker may need 100% above basal requirements. Some endurance athletes in ultradistance events can use as many as 10,000 keal/day above the basal level. Each day that your caloric intake is above what you use, fat is stored in your body and your weight rises. Each day that your caloric intake is below whatyou use, fat in your body is metabolized and your weight drops. 

In a very real sense, your body stores energy available from the metabolism of foods in the form of ATP. This molecule in turn supplies the energy required for all sorts of biochemical reactions taking place in the body. It does this by reverting to ADP, that is, by reversing reaction 17.6. The amount of ATP consumed is amazingly large a competitive sprinter may hydrolyze as much as 500 g (about 1 lb) of ATP per minute. 

Your body contains about 140 g of cholesterol it is synthesized in the liver at the rate of 2 to 3 g/day. Cholesterol is essential to life for two reasons. It is a major component of all cell membranes, and it serves as the starting material tor the synthesis of sex hormones, adrenal hormones, bile acids, and vitamin D. 

The many millions of DNA molecules in the cells of your body are identical to each other. That is, the base sequence in all of these molecules is the same. In contrast, the base sequence of the DNA molecules in every other person in the world differs at least slightly from yours. In that sense, your "DNA fingerprint" is unique. 

If your thoughts remain lofty, if a fine Emotion touches your body and your spirit. 

Triglycerides are fats. The fats in butter and bacon, like the fats in your body, are made of triglycerides. 

C.18 (a) Determine the total number of protons, neutrons, and electrons in one water molecule, H20, assuming that only the most common isotopes, H and 160, are present, (b) What are the total masses of protons, neutrons, and electrons in this water molecule (c) What fraction of your own mass is due to the neutrons in your body, assuming that you consist primarily of water made from this type of molecule Note The masses of free protons and neutrons are slightly higher than the masses of these particles in atoms so the answer is only an approximation. 

Assume that the width of your body (across your shoulders) is 20. inches and the depth of your body (chest to back) is... 

A human body generates heat at the rate of about 100. W (1 W = l J-s ). (a) At what rate does your body heat generate entropy in your surroundings, taken to be at 20.°C (b) How much entropy do you generate each day (c) Would the entropy generated he greater or less if you were in a room kept at 30.°C Explain your answer. 

During normal activity, a person uses the equivalent of about 10 MJ of energy a day. Assume that this value represents AG, and estimate the average current through your body in the course of a day, assuming that all the energy that we use arises from the reduction of 02 in the glucose oxidation reaction. See Box 12.1. 

The principal source of radioactivity in the human body is potassium-40. About 35 000 potassium-40 nuclei disintegrated in your body while you were reading this sentence. 

The water Coleridge referred to was seawater. The boards shrank due to osmosis (a net movement of water from the cells of the wood to the saline water). The same happens to the cells of your body when you drink seawater, which causes serious health problems and even death. 

Methyl parathion can enter your body if you eat food or drink water containing it if you swim, bathe, or shower in contaminated water if you touch recently sprayed plants or soil if you touch contaminated soil near hazardous waste sites or if you breathe air that contains methyl parathion, such as near factories or recently sprayed farm fields (or in recent accounts of the illegal use of methyl parathion, if you breathe air or touch contaminated surfaces inside homes where methyl parathion has been used to kill insects). By any means of exposure, methyl parathion goes into your body quickly and gets into your blood. From your bloodstream, methyl parathion goes to your liver, brain, and other organs. Your liver changes some of methyl parathion to a more harmful chemical called methyl paraoxon. Both methyl parathion and methyl paraoxon can bind to enzymes of your nerves within minutes or hours. Your liver breaks down methyl parathion and methyl paraoxon into less harmful substances. These less harmful substances leave your body in urine within hours or days. For more information, see Chapter 3. 

Several medical tests can determine whether you have been exposed to methyl parathion. The first medical test measures methyl parathion in your blood or measures 4-nitrophenol, which is a breakdown product of methyl parathion, in your urine. These tests are only reliable for about 24 hours after you are exposed because methyl parathion breaks down quickly and leaves your body. These tests cannot tell whether you will have harmful health effects or what those effects may be. The next medical test measures the levels of a substance called cholinesterase in your blood. If cholinesterase levels are less than half of what they should be and you have been exposed to methyl parathion, then you may get symptoms of poisoning. However, lower cholinesterase levels may also only indicate exposure and not necessarily harmful effects. The action of methyl parathion may cause lower cholinesterase levels in your red blood cells or your blood plasma. Such lowering, however, can also be caused by factors other than methyl parathion. For example, cholinesterase values may already be low in some people, because of heredity or disease. However, a lowering of cholinesterase levels can often show whether methyl parathion or similar compounds have acted on your nerves. Cholinesterase levels in red blood cells can stay low for more than a month after you have been exposed to methyl parathion or similar chemicals. For more information, see Chapters 3 and 7. 

When you bake in the sun, your body absorbs energy from sunlight. Infrared radiation from a heat lamp in a restaurant keeps food warm until the server delivers the meal to the customer. When a microwave oven cooks food, the food absorbs energy from microwave radiation. Sunlight, infrared light, and microwaves are examples of electromagnetic radiation, which possesses radiant energy, as we discuss in Chapter 7. 

Trichloroethylene enters your body when you breathe air or drink water containing it. It can also enter your body if you get it on your skin. You could be exposed to contaminated water or air if you live near or work in a factory that uses trichloroethylene or if you live near a waste disposal site that contains trichloroethylene. If you breathe the chemical, about half the amount you breathe in will get into your bloodstream and organs. You will exhale the rest. If you drink trichloroethylene, most of it will be absorbed into your blood. If trichloroethylene comes in contact with your skin, some of it can enter your body, although not as easily as when you breathe or swallow it. 

Once in your blood, your liver changes much of the trichloroethylene into other chemicals. The majority of these breakdown products leave your body in the urine within a day. You will also quickly breathe out much of the trichloroethylene that is in your bloodstream. Some of the trichloroethylene or its breakdown products can be stored in body fat for a brief period, and thus may build up in your body if exposure continues. For more information on trichloroethylene in your body, see Chapter 2. 

There are some tests that can show if you have been recently exposed to trichloroethylene since this chemical can be measured in your breath. Also, a doctor can have trichloroethylene or a number of breakdown products of trichloroethylene measured in your urine or blood. None of these tests, however, is routinely available at your doctor s office. If the measurements are done soon after the exposure, the breath levels can indicate whether you have been exposed to a large amount of trichloroethylene or only a small amount. Urine and blood tests can also show if you have been exposed to large amounts of this chemical. Because one of the breakdown products leaves your body very slowly, it can be measured in the urine for up to about 1 week after trichloroethylene exposure. However, exposure to other similar chemicals can produce the same breakdown products in your urine and blood. Therefore, these methods cannot determine for sure whether you have been exposed to trichloroethylene. For more information on medical tests, see Chapters 2 and 6. 

The processes that create molecules, from tiny to huge, are called chemical reactions. A reaction occurs when two or more atoms or molecules form new molecules. Saying it in a different way, a chemical reaction occurs when a chemical transformation or change takes place. When two hydrogen atoms unite to form H2, a chemical reaction has occurred. When cesium and fluorine react vigorously, a chemical reaction has taken place. Many different chemical reactions have to happen for your body to manufacture a complex molecule like hemoglobin. 

Buffers in your body are constantly working to prevent harmful increases or decreases in the pH of your blood, urine, and other fluids. In order to resist such changes, a buffer is composed of —... 

What parts of your body are ionic compounds Those that compose your skin Your hair Actually, most of the human body is composed of nonionic compounds. But, you could not live without sodium chloride and other ionic compounds found inside you. How can you distinguish ionic compounds from other types of compounds By investigating sodium chloride, you will explore some of the common properties of ionic compounds. 

Examine the entire front of your body in a full-length mirror. Look at your eyes, lips, hairline, chest, abdomen, pubic area, thighs, and lower legs. Lift your arms over your head and examine the right and left sides of your body. 

Most physicians do not test for americium in their offices, but they can collect samples and send them to special laboratories. Since americium is radioactive, it is normally measured by its radiation emissions. These emissions are used to tell the amount of americium (in curies or Becquerels) and the radiation dose it gives to your body (in Sieverts or rem). Radiation detectors measure the radiation that is released from objects or materials, including the whole body. If... 

Diisopropyl methylphosphonate may enter your body after drinking water contaminated with it or it may enter through your skin. You could be exposed to diisopropyl methylphosphonate if you drink water that contains the chemical near the RMA. Exposure of the general population to diisopropyl methylphosphonate is not likely to occur. Studies in animals show that diisopropyl methylphosphonate enters the bloodstream relatively quickly following oral exposure. Animal... 

Very little is known about how mineral oil hydraulic fluids, polyalphaolefin hydraulic fluids, and organophosphate ester hydraulic fluids enter and leave your body. Some information exists about how some of the chemical components in the organophosphate ester hydraulic fluids enter and leave your body. 

We know that chemical components of mineral oil hydraulic fluids can enter the body if you swallow them or they come in contact with your skin because health effects have occurred in people after they swallowed or had prolonged skin contact with certain mineral oil hydraulic fluids. Health effects have occurred in animals after they breathed, swallowed, or had skin contact with organophosphate ester hydraulic fluids. We do not know if mineral oil hydraulic fluids or polyalphaolefin hydraulic fluids will enter your body from your lungs if you breathe them as vapor or oil mist. 

During the cleanse, it is best to avoid stimulants such as coffee, tea or sedatives such as alcohol. Avoid smoking. A calm emotional body is also best during this time. Do what it takes to be relaxed and avoid violent TV or novels. Spend time resting, contemplating nature or soaking in warm water scented with essential oils. Enjoy the process of purifying your body and mind. 

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