A poisonous, yellowish-green gas with powerful bleaching and disinfecting properties.
Inhaling even small amounts is highly irritating to the lungs; large amounts are rapidly fatal.
Inhaling even small amounts is highly irritating to the lungs; large amounts are rapidly fatal.
Symptoms In most cases, death from asphyxia is due to insu?ciency of oxygen supplied to the blood. The ?rst signs are rapid pulse and gasping for breath. Next comes a rise in the blood pressure, causing throbbing in the head, with lividity or blueness of the skin, due to failure of aeration of the blood, followed by still greater struggles for breath and by general CONVULSIONS. The heart becomes overdistended and gradually weaker, a paralytic stage sets in, and all struggling and breathing slowly cease. When asphyxia is due to charcoal fumes, coal-gas, and other narcotic in?uences, there is no convulsive stage, and death ensues gently and may occur in the course of sleep.
Treatment So long as the heart continues to beat, recovery may be looked for with prompt treatment. The one essential of treatment is to get the impure blood aerated by arti?cial respiration. Besides this, the feeble circulation can be helped by various methods. (See APPENDIX 1: BASIC FIRST AID – Choking; Cardiac/respiratory arrest.)... asphyxia
Nutritional Profile Energy value (calories per serving): Low Protein: Trace Fat: Trace Saturated fat: None Cholesterol: None Carbohydrates: Trace Fiber: Trace Sodium: Low Major vitamin contribution: None Major mineral contribution: None
About the Nutrients in This Food Coffee beans are roasted seeds from the fruit of the evergreen coffee tree. Like other nuts and seeds, they are high in proteins (11 percent), sucrose and other sugars (8 percent), oils (10 to 15 percent), assorted organic acids (6 percent), B vitamins, iron, and the central nervous system stimulant caffeine (1 to 2 percent). With the exceptions of caffeine, none of these nutrients is found in coffee. Like spinach, rhubarb, and tea, coffee contains oxalic acid (which binds calcium ions into insoluble compounds your body cannot absorb), but this is of no nutritional consequence as long as your diet contains adequate amounts of calcium-rich foods. Coffee’s best known constituent is the methylxanthine central ner- vous system stimulant caffeine. How much caffeine you get in a cup of coffee depends on how the coffee was processed and brewed. Caffeine is Caffeine Content/Coffee Servings Brewed coffee 60 mg/five-ounce cup Brewed/decaffeinated 5 mg/five-ounce cup Espresso 64 mg/one-ounce serving Instant 47 mg/rounded teaspoon
The Most Nutritious Way to Serve This Food In moderation, with high-calcium foods. Like spinach, rhubarb, and tea, coffee has oxalic acid, which binds calcium into insoluble compounds. This will have no important effect as long as you keep your consumption moderate (two to four cups of coffee a day) and your calcium consumption high.
Diets That May Restrict or Exclude This Food Bland diet Gout diet Diet for people with heart disease (regular coffee)
Buying This Food Look for: Ground coffee and coffee beans in tightly sealed, air- and moisture-proof containers. Avoid: Bulk coffees or coffee beans stored in open bins. When coffee is exposed to air, the volatile molecules that give it its distinctive flavor and richness escape, leaving the coffee flavorless and/or bitter.
Storing This Food Store unopened vacuum-packed cans of ground coffee or coffee beans in a cool, dark cabinet—where they will stay fresh for six months to a year. They will lose some flavor in storage, though, because it is impossible to can coffee without trapping some flavor- destroying air inside the can. Once the can or paper sack has been opened, the coffee or beans should be sealed as tight as possible and stored in the refrigerator. Tightly wrapped, refrigerated ground coffee will hold its freshness and flavor for about a week, whole beans for about three weeks. For longer storage, freeze the coffee or beans in an air- and moistureproof container. ( You can brew coffee directly from frozen ground coffee and you can grind frozen beans without thawing them.)
Preparing This Food If you make your coffee with tap water, let the water run for a while to add oxygen. Soft water makes “cleaner”-tasting coffee than mineral-rich hard water. Coffee made with chlorinated water will taste better if you refrigerate the water overnight in a glass (not plastic) bottle so that the chlorine evaporates. Never make coffee with hot tap water or water that has been boiled. Both lack oxygen, which means that your coffee will taste flat. Always brew coffee in a scrupulously clean pot. Each time you make coffee, oils are left on the inside of the pot. If you don’t scrub them off, they will turn rancid and the next pot of coffee you brew will taste bitter. To clean a coffee pot, wash it with detergent, rinse it with water in which you have dissolved a few teaspoons of baking soda, then rinse one more time with boiling water.
What Happens When You Cook This Food In making coffee, your aim is to extract flavorful solids (including coffee oils and sucrose and other sugars) from the ground beans without pulling bitter, astringent tannins along with them. How long you brew the coffee determines how much solid material you extract and how the coffee tastes. The longer the brewing time, the greater the amount of solids extracted. If you brew the coffee long enough to extract more than 30 percent of its solids, you will get bitter compounds along with the flavorful ones. (These will also develop by let- ting coffee sit for a long time after brewing it.) Ordinarily, drip coffee tastes less bitter than percolator coffee because the water in a drip coffeemaker goes through the coffee only once, while the water in the percolator pot is circulated through the coffee several times. To make strong but not bitter coffee, increase the amount of coffee—not the brewing time.
How Other Kinds of Processing Affect This Food Drying. Soluble coffees (freeze-dried, instant) are made by dehydrating concentrated brewed coffee. These coffees are often lower in caffeine than regular ground coffees because caffeine, which dissolves in water, is lost when the coffee is dehydrated. Decaffeinating. Decaffeinated coffee is made with beans from which the caffeine has been extracted, either with an organic solvent (methylene chloride) or with water. How the coffee is decaffeinated has no effect on its taste, but many people prefer water-processed decaf- feinated coffee because it is not a chemically treated food. (Methylene chloride is an animal carcinogen, but the amounts that remain in coffees decaffeinated with methylene chloride are so small that the FDA does not consider them hazardous. The carcinogenic organic sol- vent trichloroethylene [TCE], a chemical that causes liver cancer in laboratory animals, is no longer used to decaffeinate coffee.)
Medical Uses and/or Benefits As a stimulant and mood elevator. Caffeine is a stimulant. It increases alertness and concentra- tion, intensifies muscle responses, quickens heartbeat, and elevates mood. Its effects derive from the fact that its molecular structure is similar to that of adenosine, a natural chemical by-product of normal cell activity. Adenosine is a regular chemical that keeps nerve cell activ- ity within safe limits. When caffeine molecules hook up to sites in the brain when adenosine molecules normally dock, nerve cells continue to fire indiscriminately, producing the jangly feeling sometimes associated with drinking coffee, tea, and other caffeine products. As a rule, it takes five to six hours to metabolize and excrete caffeine from the body. During that time, its effects may vary widely from person to person. Some find its stimu- lation pleasant, even relaxing; others experience restlessness, nervousness, hyperactivity, insomnia, flushing, and upset stomach after as little as one cup a day. It is possible to develop a tolerance for caffeine, so people who drink coffee every day are likely to find it less imme- diately stimulating than those who drink it only once in a while. Changes in blood vessels. Caffeine’s effects on blood vessels depend on site: It dilates coronary and gastrointestinal vessels but constricts blood vessels in your head and may relieve headache, such as migraine, which symptoms include swollen cranial blood vessels. It may also increase pain-free exercise time in patients with angina. However, because it speeds up heartbeat, doc- tors often advise patients with heart disease to avoid caffeinated beverages entirely. As a diuretic. Caffeine is a mild diuretic sometimes included in over-the-counter remedies for premenstrual tension or menstrual discomfort.
Adverse Effects Associated with This Food Stimulation of acid secretion in the stomach. Both regular and decaffeinated coffees increase the secretion of stomach acid, which suggests that the culprit is the oil in coffee, not its caffeine. Elevated blood levels of cholesterol and homocysteine. In the mid-1990s, several studies in the Netherlands and Norway suggested that drinking even moderate amounts of coffee (five cups a day or less) might raise blood levels of cholesterol and homocysteine (by-product of protein metabolism considered an independent risk factor for heart disease), thus increas- ing the risk of cardiovascular disease. Follow-up studies, however, showed the risk limited to drinking unfiltered coffees such as coffee made in a coffee press, or boiled coffees such as Greek, Turkish, or espresso coffee. The unfiltered coffees contain problematic amounts of cafestol and kahweol, two members of a chemical family called diterpenes, which are believed to affect cholesterol and homocysteine levels. Diterpenes are removed by filtering coffee, as in a drip-brew pot. Possible increased risk of miscarriage. Two studies released in 2008 arrived at different conclusions regarding a link between coffee consumption and an increased risk of miscar- riage. The first, at Kaiser Permanente (California), found a higher risk of miscarriage among women consuming even two eight-ounce cups of coffee a day. The second, at Mt. Sinai School of Medicine (New York), found no such link. However, although the authors of the Kaiser Permanente study described it as a “prospective study” (a study in which the research- ers report results that occur after the study begins), in fact nearly two-thirds of the women who suffered a miscarriage miscarried before the study began, thus confusing the results. Increased risk of heartburn /acid reflux. The natural oils in both regular and decaffeinated coffees loosen the lower esophageal sphincter (LES), a muscular valve between the esopha- gus and the stomach. When food is swallowed, the valve opens to let food into the stomach, then closes tightly to keep acidic stomach contents from refluxing (flowing backwards) into the esophagus. If the LES does not close efficiently, the stomach contents reflux and cause heartburn, a burning sensation. Repeated reflux is a risk factor for esophageal cancer. Masking of sleep disorders. Sleep deprivation is a serious problem associated not only with automobile accidents but also with health conditions such as depression and high blood pres- sure. People who rely on the caffeine in a morning cup of coffee to compensate for lack of sleep may put themselves at risk for these disorders. Withdrawal symptoms. Caffeine is a drug for which you develop a tolerance; the more often you use it, the more likely you are to require a larger dose to produce the same effects and the more likely you are to experience withdrawal symptoms (headache, irritation) if you stop using it. The symptoms of coffee-withdrawal can be relieved immediately by drinking a cup of coffee.
Food/Drug Interactions Drugs that make it harder to metabolize caffeine. Some medical drugs slow the body’s metabolism of caffeine, thus increasing its stimulating effect. The list of such drugs includes cimetidine (Tagamet), disulfiram (Antabuse), estrogens, fluoroquinolone antibiotics (e.g., ciprofloxacin, enoxacin, norfloxacin), fluconazole (Diflucan), fluvoxamine (Luvox), mexi- letine (Mexitil), riluzole (R ilutek), terbinafine (Lamisil), and verapamil (Calan). If you are taking one of these medicines, check with your doctor regarding your consumption of caf- feinated beverages. Drugs whose adverse effects increase due to consumption of large amounts of caffeine. This list includes such drugs as metaproterenol (Alupent), clozapine (Clozaril), ephedrine, epinephrine, monoamine oxidase inhibitors, phenylpropanolamine, and theophylline. In addition, suddenly decreasing your caffeine intake may increase blood levels of lithium, a drug used to control mood swings. If you are taking one of these medicines, check with your doctor regarding your consumption of caffeinated beverages. Allopurinol. Coffee and other beverages containing methylxanthine stimulants (caffeine, theophylline, and theobromine) reduce the effectiveness of the antigout drug allopurinol, which is designed to inhibit xanthines. Analgesics. Caffeine strengthens over-the-counter painkillers (acetaminophen, aspirin, and other nonsteroidal anti-inflammatories [NSAIDS] such as ibuprofen and naproxen). But it also makes it more likely that NSAIDS will irritate your stomach lining. Antibiotics. Coffee increases stomach acidity, which reduces the rate at which ampicillin, erythromycin, griseofulvin, penicillin, and tetracyclines are absorbed when they are taken by mouth. (There is no effect when the drugs are administered by injection.) Antiulcer medication. Coffee increases stomach acidity and reduces the effectiveness of nor- mal doses of cimetidine and other antiulcer medication. False-positive test for pheochromocytoma. Pheochromocytoma, a tumor of the adrenal glands, secretes adrenalin, which is converted to VM A (vanillylmandelic acid) by the body and excreted in the urine. Until recently, the test for this tumor measured the levels of VM A in the patient’s urine and coffee, which contains VM A, was eliminated from patients’ diets lest it elevate the level of VM A in the urine, producing a false-positive test result. Today, more finely drawn tests make this unnecessary. Iron supplements. Caffeine binds with iron to form insoluble compounds your body cannot absorb. Ideally, iron supplements and coffee should be taken at least two hours apart. Birth control pills. Using oral contraceptives appears to double the time it takes to eliminate caffeine from the body. Instead of five to six hours, the stimulation of one cup of coffee may last as long as 12 hours. Monoamine oxidase (MAO) inhibitors. Monoamine oxidase inhibitors are drugs used to treat depression. They inactivate naturally occurring enzymes in your body that metabolize tyra- mine, a substance found in many fermented or aged foods. Tyramine constricts blood vessels and increases blood pressure. Caffeine is a substance similar to tyramine. If you consume excessive amounts of a caffeinated beverage such as coffee while you are taking an M AO inhibitor, the result may be a hypertensive crisis. Nonprescription drugs containing caffeine. The caffeine in coffee may add to the stimulant effects of the caffeine in over-the-counter cold remedies, diuretics, pain relievers, stimulants, and weight-control products containing caffeine. Some cold pills contain 30 mg caffeine, some pain relievers 130 mg, and some weight-control products as much as 280 mg caffeine. There are 110 –150 mg caffeine in a five-ounce cup of drip-brewed coffee. Sedatives. The caffeine in coffee may counteract the drowsiness caused by sedative drugs; this may be a boon to people who get sleepy when they take antihistamines. Coffee will not, however, “sober up” people who are experiencing the inebriating effects of alcoholic beverages. Theophylline. Caffeine relaxes the smooth muscle of the bronchi and may intensif y the effects (and/or increase the risk of side effects) of this antiasthmatic drug.... coffee
Varieties Volatile oils of plants, such as eucalyptus and turpentine, chlorine water and chlorinated lime, peroxide of hydrogen and charcoal have been used as deodorants. There are now many commercial products available.... deodorants
Nutritional Profile Energy value (calories per serving): High Protein: Moderate Fat: Low Saturated fat: Low Cholesterol: None Carbohydrates: High Fiber: Low to high Sodium: Low (except self-rising flour) Major vitamin contribution: B vitamins Major mineral contribution: Iron
About the Nutrients in This Food Flour is the primary source of the carbohydrates (starch and fiber) in bread, pasta, and baked goods. All wheat and rye flours also provide some of the food fibers, including pectins, gums, and cellulose. Flour also contains significant amounts of protein but, like other plant foods, its proteins are “incomplete” because they are deficient in the essential amino acid lysine. The fat in the wheat germ is primarily polyunsaturated; flour contains no cholesterol. Flour is a good source of iron and the B vitamins. Iodine and iodophors used to clean the equipment in grain-processing plants may add iodine to the flour. In 1998, the Food and Drug Administration ordered food manufac- turers to add folates—which protect against birth defects of the spinal cord and against heart disease—to flour, rice, and other grain products. One year later, data from the Framingham Heart Study, which has fol- lowed heart health among residents of a Boston suburb for nearly half a century, showed a dramatic increase in blood levels of folic acid. Before the fortification of foods, 22 percent of the study participants had a folic acid deficiency; after, the number fell to 2 percent. Whole grain flour, like other grain products, contains phytic acid, an antinutrient that binds calcium, iron, and zinc ions into insoluble com- pounds your body cannot absorb. This has no practical effect so long as your diet includes foods that provide these minerals. Whole wheat flours. Whole wheat flours use every part of the kernel: the fiber-rich bran with its B vitamins, the starch- and protein-rich endosperm with its iron and B vitamins, and the oily germ with its vitamin E.* Because they contain bran, whole-grain flours have much more fiber than refined white flours. However, some studies suggest that the size of the fiber particles may have some bearing on their ability to absorb moisture and “bulk up” stool and that the fiber particles found in fine-ground whole wheat flours may be too small to have a bulking effect. Finely ground whole wheat flour is called whole wheat cake flour; coarsely ground whole wheat flour is called graham flour. Cracked wheat is a whole wheat flour that has been cut rather than ground; it has all the nutrients of whole wheat flour, but its processing makes it less likely to yield its starch in cooking. When dried and parboiled, cracked wheat is known as bulgur, a grain used primarily as a cereal, although it can be mixed with other flours and baked. Gluten flour is a low-starch, high-protein product made by drying and grinding hard- wheat flour from which the starch has been removed. Refined (“white”) flours. Refined flours are paler than whole wheat flours because they do not contain the brown bran and germ. They have less fiber and fat and smaller amounts of vitamins and minerals than whole wheat flours, but enriched refined flours are fortified with B vitamins and iron. Refined flour has no phytic acid. Some refined flours are bleached with chlorine dioxide to destroy the xanthophylls (carotenoid pigments) that give white flours a natural cream color. Unlike carotene, the carotenoid pigment that is converted to vitamin A in the body, xanthophylls have no vita- min A activity; bleaching does not lower the vitamin A levels in the flour, but it does destroy vitamin E. There are several kinds of white flours. All-purpose white flour is a mixture of hard and soft wheats, high in protein and rich in gluten.t Cake flour is a finely milled soft-wheat flour; it has less protein than all-purpose flour. Self-rising flour is flour to which baking powder has been added and is very high in sodium. Instant flour is all-purpose flour that has been ground extra-fine so that it will combine quickly with water. Semolina is a pale high-protein, low- gluten flour made from durum wheat and used to make pasta. Rye flours. Rye flour has less gluten than wheat flour and is less elastic, which is why it makes a denser bread.:j Like whole wheat flour, dark rye flour (the flour used for pumpernickel bread) contains the bran and the germ of the rye grain; light rye flour (the flour used for ordinary rye bread) The bran is t he kernel’s hard, brown outer cover, an ext raordinarily rich source of cellulose and lignin. The endosperm is t he kernel’s pale interior, where t he vitamins abound. The germ, a small part icle in t he interior, is t he part of t he kernel t hat sprouts. Hard wheat has less starch and more protein t han soft wheat. It makes a heavier, denser dough. Gluten is t he st icky substance formed when k neading t he dough relaxes t he long-chain molecules in t he proteins gliadin and glutenin so t hat some of t heir intermolecular bonds (bonds bet ween atoms in t he same molecule) break and new int ramolecular bonds (bonds bet ween atoms on different mol- ecules) are formed. Triticale flour is milled from triticale grain, a rye/wheat hybrid. It has more protein and less gluten than all-purpose wheat flour.
The Most Nutritious Way to Serve This Food With beans or a “complete” protein food (meat, fish, poultry, eggs, milk, cheese) to provide the essential amino acid lysine, in which wheat and rye flours are deficient.
Diets That May Restrict or Exclude This Food Low-calcium diet (whole grain and self-rising flours) Low-fiber diet (whole wheat flours) Low-gluten diet (all wheat and rye flour) Sucrose-free diet
Buying This Food Look for: Tightly sealed bags or boxes. Flours in torn packages or in open bins are exposed to air and to insect contamination. Avoid: Stained packages—the liquid that stained the package may have seeped through into the flour.
Storing This Food Store all flours in air- and moistureproof canisters. Whole wheat flours, which contain the germ and bran of the wheat and are higher in fat than white flours, may become rancid if exposed to air; they should be used within a week after you open the package. If you plan to hold the flour for longer than that, store it in the freezer, tightly wrapped to protect it against air and moisture. You do not have to thaw the flour when you are ready to use it; just measure it out and add it directly to the other ingredients. Put a bay leaf in the flour canister to help protect against insect infections. Bay leaves are natural insect repellents.
What Happens When You Cook This Food Protein reactions. The wheat kernel contains several proteins, including gliadin and glute- nin. When you mix flour with water, gliadin and glutenin clump together in a sticky mass. Kneading the dough relaxes the long gliadin and glutenin molecules, breaking internal bonds between individual atoms in each gliadin and glutenin molecule and allowing the molecules to unfold and form new bonds between atoms in different molecules. The result is a network structure made of a new gliadin-glutenin compound called gluten. Gluten is very elastic. The gluten network can stretch to accommodate the gas (carbon dioxide) formed when you add yeast to bread dough or heat a cake batter made with baking powder or baking soda (sodium bicarbonate), trapping the gas and making the bread dough or cake batter rise. When you bake the dough or batter, the gluten network hardens and the bread or cake assumes its finished shape. Starch reactions. Starch consists of molecules of the complex carbohydrates amylose and amylopectin packed into a starch granule. When you heat flour in liquid, the starch gran- ules absorb water molecules, swell, and soften. When the temperature of the liquid reaches approximately 140°F the amylose and amylopectin molecules inside the granules relax and unfold, breaking some of their internal bonds (bonds between atoms on the same molecule) and forming new bonds between atoms on different molecules. The result is a network that traps and holds water molecules. The starch granules then swell, thickening the liquid. If you continue to heat the liquid (or stir it too vigorously), the network will begin to break down, the liquid will leak out of the starch granules, and the sauce will separate.* Combination reaction. Coating food with flour takes advantage of the starch reaction (absorbing liquids) and the protein reaction (baking a hard, crisp protein crust).
Medical Uses and/or Benefits A lower risk of some kinds of cancer. In 1998, scientists at Wayne State University in Detroit conducted a meta-analysis of data from more than 30 well-designed animal studies mea- suring the anti-cancer effects of wheat bran, the part of grain with highest amount of the insoluble dietary fibers cellulose and lignin. They found a 32 percent reduction in the risk of colon cancer among animals fed wheat bran; now they plan to conduct a similar meta- analysis of human studies. Whole wheat flours are a good source of wheat bran. NOTE : The amount of fiber per serving listed on a food package label shows the total amount of fiber (insoluble and soluble). Early in 1999, however, new data from the long-running Nurses Health Study at Brigham Women’s Hospital/Harvard University School of Public Health showed that women who ate a high-fiber diet had a risk of colon cancer similar to that of women who ate a low-fiber diet. * A mylose is a long, unbranched, spiral molecule; amylopect in is a short, compact, branched molecule. A mylose has more room for forming bonds to water. Wheat flours, which have a higher rat io of amy- lose to amylopect in, are superior t hickeners. Because this study contradicts literally hundreds of others conducted over the past 30 years, researchers are awaiting confirming evidence before changing dietary recommendations.
Adverse Effects Associated with This Food Allergic reactions. According to the Merck Manual, wheat is one of the foods most commonly implicated as a cause of allergic upset stomach, hives, and angioedema (swollen lips and eyes). For more information, see under wheat cer ea ls. Gluten intolerance (celiac disease). Celiac disease is an intestinal allergic disorder that makes it impossible to digest gluten and gliadin (proteins found in wheat and some other grains). Corn flour, potato flour, rice flour, and soy flour are all gluten- and gliadin-free. Ergot poisoning. Rye and some kinds of wheat will support ergot, a parasitic fungus related to lysergic acid (LSD). Because commercial flours are routinely checked for ergot contamina- tion, there has not been a major outbreak of ergot poisoning from bread since a 1951 incident in France. Since baking does not destroy ergot toxins, the safest course is to avoid moldy flour altogether.... flour
Adult kidneys have a smooth exterior, enveloped by a tough ?brous coat that is bound to the kidney only by loose ?brous tissue and by a few blood vessels that pass between it and the kidney. The outer margin of the kidney is convex; the inner is concave with a deep depression, known as the hilum, where the vessels enter. The URETER, which conveys URINE to the URINARY BLADDER, is also joined at this point. The ureter is spread out into an expanded, funnel-like end, known as the pelvis, which further divides up into little funnels known as the calyces. A vertical section through a kidney (see diagram) shows two distinct layers: an outer one, about 4 mm thick, known as the cortex; and an inner one, the medulla, lying closer to the hilum. The medulla consists of around a dozen pyramids arranged side by side, with their base on the cortex and their apex projecting into the calyces of the ureter. The apex of each pyramid is studded with tiny holes, which are the openings of the microscopic uriniferous tubes.
In e?ect, each pyramid, taken together with the portion of cortex lying along its base, is an independent mini-kidney. About 20 small tubes are on the surface of each pyramid; these, if traced up into its substance, repeatedly subdivide so as to form bundles of convoluted tubules, known as medullary rays, passing up towards the cortex. One of these may be traced further back, ending, after a tortuous course, in a small rounded body: the Malpighian corpuscle or glomerulus (see diagram). Each glomerulus and its convoluted tubule is known as a nephron, which constitutes the functional unit of the kidney. Each kidney contains around a million nephrons.
After entering the kidney, the renal artery divides into branches, forming arches where the cortex and medulla join. Small vessels come o? these arches and run up through the cortex, giving o? small branches in each direction. These end in a tuft of capillaries, enclosed in Bowman’s capsule, which forms the end of the uriniferous tubules just described; capillaries with capsule constitute a glomerulus.
After circulating in the glomerulus, the blood leaves by a small vein, which again divides into capillaries on the walls of the uriniferous tubules. From these it is ?nally collected into the renal veins and then leaves the kidney. This double circulation (?rst through the glomerulus and then around the tubule) allows a large volume of ?uid to be removed from the blood in the glomerulus, the concentrated blood passing on to the uriniferous tubule for removal of parts of its solid contents. Other arteries come straight from the arches and supply the medulla direct; the blood from these passes through another set of capillaries and ?nally into the renal veins. This circulation is con?ned purely to the kidney, although small connections by both arteries and veins exist which pass through the capsule and, joining the lumbar vessels, communicate directly with the aorta.
Function The kidneys work to separate ?uid and certain solids from the blood. The glomeruli ?lter from the blood the non-protein portion of the plasma – around 150–200 litres in 24 hours, 99 per cent of which is reabsorbed on passing through the convoluted tubules.
Three main groups of substances are classi?ed according to their extent of uptake by the tubules:
(1) SUBSTANCES ACTIVELY REABSORBED These include amino acids, glucose, sodium, potassium, calcium, magnesium and chlorine (for more information, see under separate entries).
(2) SUBSTANCES DIFFUSING THROUGH THE TUBULAR EPITHELIUM when their concentration in the ?ltrate exceeds that in the PLASMA, such as UREA, URIC ACID and phosphates.
(3) SUBSTANCES NOT RETURNED TO THE BLOOD from the tubular ?uid, such as CREATINE, accumulate in kidney failure, resulting in general ‘poisoning’ known as URAEMIA.... structure each kidney is about 10 cm long,
Habitat: Native to Europe; grown in Himachal Pradesh and Maharashtra.
English: Salify, Vegetable-Oyster, Purple Goat's Beard, Oyster Plant.Action: Root—specific in obstructions of the gall in jaundice; antibilious. Also used for treating arteriosclerosis and high blood pressure.
T. porrifolius contain several flavo- noids, including orientin and iso- orientin.The seeds yield an oil which contains a saturated epoxy acid viz. cis-9, 10-epoxysteric acid and several conjugated dienoic acids.Cooked flashy roots of T. porrifolius contain sodium 8, potassium 183, calcium 60, magnesium 14, iron 1.2, copper 0.1, phosphorus 53, sulphur 25 and chlorine 46 mg/100 g. A large parts of carbohydrates occur as inulin.... tragopogon porrifolius
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