Chapter 23 Metabolism, Nutrition, and Energetics
Identify the fates of fatty acids. (Module 23.11C)
Fatty acid may become a fuel source of or a component of triglycerides, glycolipids, phospholipids, prostaglandins, cholesterol and steroid.
Describe the roles of LDLs and HDLs. (Module 23.10C)
LDLs delivers cholesterol to tissues, HDL’s absorb unused cholesterol and return to the liver.
During lipolysis,
Triglycerides are broken down into glycerol and fatty acids
Lipogenesis generally begins with
Acetyl-CoA
Define beta-oxidation. (Module 23.11A)
Fatty acid catabolism
The nutrients that yield the most energy per gram when metabolized are
Lipids
Where does most nutrient absorption occur? (Module 23.8B)
In the Small intestine, primarily in the jejunum.
All of the following take place during the absorptive state except
Ketone bodies begin to form
When and how do ketone bodies form? (Module 23.13B)
During postabsorbptive state when carbohydrates are broken down by the liver.
Glucocorticoids have which of the following effects on general peripheral tissues?
All of the answers are correct.
Wally decides to go on a hunger strike to further one of his favorite causes. After many days with nothing but water you would expect to observe
All of the answers are correct
What two coenzymes transfer hydrogen atoms to the electron transport chain? (Module 23.4C)
NAD and FAD
________ creates 90 percent of the ATP normally generated.
Oxidative phosphorylation
Compare oxidation and reduction. (Module 23.5B)
Oxidation is the gain of oxygen, or loss of hydrogen or electrons, whereas reduction is the loss of oxygen, or the gain of hydrogen or electron.
The sum of all of the biochemical processes going on within the human body at any given time is called
Metabolism
Although other nutrients can feed into the citric acid cycle, ________ yields energy the quickest.
Glucose
Explain when glycolysis is important in cellular metabolism. (Module 23.6B)
When ATP must be produced anaerobically
Compare glycogenesis and glycogenolysis. (Module 23.7A)
Glycogenesis is the formation of glycogen from glucose. Glycogenolysis is the breakdown of glycogen to glucose.
In oxidative phosphorylation, energy for the synthesis of ATP is directly obtained from the
Movement of hydrogen ions through channels in the inner mitochondrial membrane.
The vitamin that plays a role in maintaining epithelia and is required for the synthesis of visual pigments is vitamin
A
________ is an unhealthy state resulting from inadequate intake of one or more nutrients that becomes life-threatening as the deficiencies accumulate.
Malnutrition
Identify the two classes of vitamins. (Module 23.14B)
Fat-soluble and water-soluble
The vitamin that is required for proper bone growth and for calcium absorption and retention is vitamin
D
A high uric acid level (above 7.4 mg/dl) can lead to the painful condition known as
GOUT
Predict the effect of peripheral vasodilation on a person's body temperature. (Module 23.20A)
Body temperature would decrease
Define insensible perspiration. (Module 23.19A)
The loss of water by evaporation from the skin and alveolar surfaces of the lungs
The area of the brain that regulates body temperature is the
Hypothalamus
Of all the energy released in catabolism, about ________ percent is lost as heat warms the surrounding tissues.
60
Homeostatic control of body temperature is termed
Thermoregulation
A(n) ________ contains all of the essential amino acids.
Complete protein
Deficiency in what vitamin can result in a condition called scurvy?
C
The minimum resting energy expenditure of an awake, alert person is called
Basal metabolic state
It's been 5 hours since you had breakfast and now you're thinking about trying the new Mexican lunch place that just opened up across the street. The more you think about it, the hungrier you get. Your increased hunger is the result of the ________ that your empty stomach is releasing into your bloodstream.
Ghrelin
What happens to the ammonium ions that are removed from amino acids during deamination? (Module 23.12C
They combine with CO2 and enter the urea cycle
In amino acid metabolism, identify the processes by which the amino group is removed. (Module 23
Transamination or deamination
________ carry excess cholesterol from peripheral tissues to the liver.
High density lipoproteins (HDLs)
How are most nutrients absorbed in the digestive tract eventually transported out of the digestive system
Through the hepatic portal vein
Describe the source of intestinal gas. (Module 23.9A)
Bacterial metabolism of indigestible carbohydrates in the colon.
The lipoproteins that carry absorbed lipids from the intestinal tract to the bloodstream are the
Chylomicrons
Reactions within ________ provide most of the energy needed by a typical cell.
The Mitochondria
The carbon dioxide of respiration is formed during
The citric acid cycle
List the products of glycolysis. (Module 23.3A)
2 molecules of pyruvate,
2 molecules of ATP,
2 molecules of NADH
Briefly describe the citric acid cycle, and explain its role. (Module 23.4A)
The breakdown of organic molecules to release hydrogen atoms bound to coenzymes that can enter the electron transport chain.