HW Ch.23 Metabolism for stud PDF

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Human Anatomy and Physiology IIHuman Anatomy and Physiology IIHuman Anatomy and Physiology IIHuman Anatomy and Physiology IIHuman Anatomy and Physiology IIHuman Anatomy and Physiology IIHuman Anatomy and Physiology IIHuman Anatomy and Physiology II...

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Homework assignment. Chapter 23. Name: Dean Cooper | Date: 7/25/2021 True/False Questions 1) Beta oxidation is the initial phase of fatty acid oxidation, and it occurs in the cytoplasm. FALSE 2) The increased use of noncarbohydrate molecules for energy to conserve glucose is called glucose sparing. TRUE 3) Except for lactose and some glycogen, the carbohydrates we ingest are mainly from animals. FALSE 4) The term essential nutrient refers to the chemicals that can be interconverted in the liver so that the body can maintain life and good health. FALSE 5) The most abundant dietary lipids in the diets of most Americans are triglycerides. TRUE 6) There are no complete proteins. All animal products should be eaten with plant material to make a complete protein. FALSE 7) The body is considered to be in nitrogen balance when the amount of nitrogen ingested in lipids equals the amount excreted in urine. FALSE 12) Glycogenesis begins when ATP levels are high, and glucose entering cells is phosphorylated to glucose-6-phosphate and converted to its isomer, glucose-1-phosphate. TRUE 13) All athletes require diets high in protein and calories in order to perform and to maintain their muscle mass. FALSE 14) In order for amino acids to be oxidized for energy, the amine group (NH2) must be removed. TRUE 15) When blood glucose levels are low, the body begins to use more noncarbohydrate fuels for energy production. This process is called glucose activation. FALSE 16) Processes that break down complex molecules into simpler ones are anabolic. FALSE 17) For use as fuel, all food carbohydrates are eventually transformed to glucose. TRUE 18) Triglycerides and cholesterol do not circulate freely in the bloodstream. TRUE 19) The major role of HDLs is to store energy in the form of fat. FALSE 23) Diets high in cholesterol and saturated fats tend to produce high HDL concentrations. FALSE

24) Ghrelin, produced by the stomach, is a powerful appetite stimulant. TRUE

24.4 Fill-in-the-Blank/Short Answer Questions 1) The Krebs cycle produces two ATP molecules per glucose molecule by substrate-level phosphorylation. 2) Which nutritional state constitutes the period during and shortly after eating when nutrients are flushing into the bloodstream from the GI tract? absorptive 3) Fat burning causes an accumulation of acetyl CoA, which the liver converts to ketones 4) Low body temperature due to excessive cold is called hyperthermia 5) The enzymes that catalyze oxidation-reduction reactions by removing hydrogen are specifically called dehydrogenases 6) The process of splitting glucose through a series of steps that produces two pyruvic acid molecules is called glycolysis 9) Explain why the elderly more easily gain weight, even though they may actually eat very little. The metabolic rate of the elderly declines steadily with age as skeletal muscles begin to atrophy and activity usually declines. Even eating enough to maintain proper nutrition, the metabolic rate is so slow that not all of the food is used for energy. 10) What are the four mechanisms of heat exchange and how are they defined? (1) Radiation is the loss of heat as thermal energy. (2) Conduction is the transfer of heat between objects that are in direct contact with each other. (3) Convection is the process of replacing the warm air around the body with cooler air and thus removing body heat. (4) Evaporation cools by removing large amounts of heat as water changes state from liquid to gas 11) Define amino acid pool and explain how the pool is maintained even though we excrete amino acids daily. The amino acid pool consists of the body's total supply of free amino acids needed to resynthesize body proteins. Even though a small amount of amino acids and proteins is lost daily in urine, these are replaced through diet. If they are not replaced, the amino acids resulting from tissue breakdown become a part of the pool. 12) Hypervitaminosis may have serious consequences. Which vitamin group, water or fat

soluble, is most likely to be involved in such cases and why? Fat-soluble vitamins are most likely involved in hypervitaminosis, because they are stored in the body and excesses are not removed. 13) What is obesity, and what health problems accompany or follow its onset? Obesity is a BMI (body mass index) greater than 30. Health problems accompanying or following obesity include a higher incidence of arteriosclerosis, hypertension, coronary artery disease, and diabetes mellitus 14) How is the postabsorptive state controlled and initiated? The postabsorptive state is controlled by the interaction of the sympathetic nervous system and several hormones, especially glucagon. The trigger for initiating postabsorptive events is damping of insulin release, which occurs as blood glucose levels begin to drop. Insulin levels decline, and the insulin-induced cellular responses are inhibited. 16)) Explain what happens to pyruvic acid if oxygen is not present in sufficient quantities to support the electron transport system. When oxygen is not present in sufficient amounts, the NADH + H+ produced during glycolysis begins to unload its hydrogen "baggage" back onto pyruvic acid, reducing it. This addition of hydrogen atoms to pyruvic acid results in the production of lactic acid. 17) Define nitrogen balance. List three factors that might lead to negative nitrogen balance and three that might result in positive nitrogen balance. Nitrogen balance is a state when the amount of nitrogen ingested in proteins equals the amount of nitrogen excreted in urine and feces. Factors leading to negative nitrogen balance, when protein breakdown exceeds the use of protein for building structural or functional molecules, include physical and emotional stress, poor-quality dietary protein, and starvation. Factors leading to positive nitrogen balance, when the rate of protein synthesis is higher than the rate of its breakdown and loss, include the normal condition in growing children and pregnant women, periods of rebuilding or repair following illness, and site-specific regeneration following injury. 24.5 Clinical Questions. Choose the question(s) below. 1) After chopping wood for about 2 hours, on a hot but breezy afternoon, John stumbled into the house and immediately fainted. His T-shirt was wringing wet with perspiration, and his pulse was faint and rapid. What is your tentative diagnosis? Explain your reasoning and note what you should do to help John's recovery.

John was suffering from heat exhaustion due to excessive loss of body fluids (indicated by his wet T-shirt); his low blood pressure; and cool, clammy skin. To help his recovery, he should be given fluid and electrolyte replacement therapy and should be cooled down. 2) Harry is hospitalized with bacterial pneumonia. When you visit him, his teeth are chattering, his skin is cool and clammy to the touch, and he complains of feeling cold, even though the room is quite warm. Explain his symptoms. Harry's symptoms indicate a fever caused by his bacterial pneumonia. The white cells battling the pneumonia release pyrogens that act directly on the hypothalamus, causing its neurons to release prostaglandins. The prostaglandins reset the hypothalamic thermostat to a higher temperature, causing the body to initiate heat-promoting mechanisms. Vasoconstriction causes a decline of heat loss from the body surface, cooling of the skin, and shivering. 5) The patient is 45 years old and is obese. He states he has been on the Atkins diet and has lost 20 pounds. What are the dangers inherent in following fad diets for quick weight loss? Many fad diets are nutritionally unhealthy, particularly if they limit certain groups of nutrients. Some of the liquid high-protein diets contain poor-quality protein and are actually dangerous. 6) What are four possible complications of obesity from a medical standpoint? The obese have a higher incidence of arteriosclerosis, hypertension, coronary artery disease, and diabetes mellitus. 7) The patient is 52 years old and has a history of hypertension. His cholesterol level is 245. He states his job is very stressful and he is recently going through a divorce. He admits to being overweight and has an inactive lifestyle. His father died of a stroke at age 60. He is worried about having a heart attack and/or stroke and wishes to change his lifestyle. The nurse encourages the patient to eat more fish. Explain why eating more fish would be of benefit for this patient. The omega-3 fatty acids in cold-water fish have a powerful antiarrhythmic effect on the heart and also make blood platelets less sticky, thus helping to prevent spontaneous clotting that can block blood vessels and lower blood pressure....