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Examples of catabolism include all of the

following except ____.

1. Synthesis of new organic molecules 2. Carbohydrates being broken down into

simple sugars

3. Triglycerides splitting into fatty acids

4. Proteins being broken down into amino acids



What is the primary role of the TCA cycle in

the production of ATP?

1. Break down glucose

2. Create hydrogen gradient

3. Phosphorylate ADP

4. Transfer electrons from substrates to

coenzymes



Why is oxidative phosphorylation the most

important mechanism for generating ATP?

1. It requires less energy than other mechanisms.

2. It requires fewer steps to produce ATPmolecules.

3. It produces more than 90% of ATP used by

body cells.

4. It allows the release of a tremendous amount

of energy.



What is the electron transport system’s role in the

generation of ATP?

1. It creates a steep concentration gradientacross the inner mitochondrial membrane.

2. It manufactures 36 ATP.

3. It facilitates formation of coenzymes.

4. It prevents substrate-level phosphorylation.



NADH produced by glycolysis in skeletal muscle fibers

leads to production of two ATP molecules in

mitochondria, but NADH produced by glycolysis incardiac muscle cells leads to production of three ATP

molecules. Why?

1. Different systems

2. Different pH

3. Different intermediaries4. More efficient enzymes in cardiac

muscle



How does a decrease in the level of cytoplasmic

NAD affect ATP production in mitochondria?

1. ATP production increases. 2. ATP production decreases.

3. Pyruvic acid supplies increase.

4. Unused glucose molecules allow for

production of ATP through other mechanisms.



What is the process of gluconeogenesis?

1. The formation of glycogen from glucose

2. The synthesis of glucose from fatty acids

3. The formation of glucose from precursors

such as lactic acid

4. All of the above are correct



Why are high-density lipoproteins (HDLs)

considered beneficial?

1. They increase lipid metabolism.

2. They decrease blood pressure.

3. They increase blood pH.

4. They reduce fat and cholesterol in the

bloodstream.



What characteristic of lipoproteins allows

them to be made water-soluble?

1. They are small enough to pass through the

plasma membrane.

2. They have superficial coating of phospholipids

and proteins.

3. They form compact granules.

4. They provide more energy than a comparable

amount of glucose.



Why are LDLs considered “bad cholesterol”?

1. They take cholesterol from peripheral

tissues to the liver.

2. They deliver cholesterol to peripheral

tissues.

3. They often end up in arterial plaques.

4. 2 and 3 are correct.



What happens during the process of

transamination?

1. An amino group and hydrogen atom are

removed.

2. The toxic compound ammonium (NH4) iscreated.

3. A keto acid is converted into an amino acid

that can leave the mitochondria.4. The liver breaks down internal proteins.



Why does a diet that is deficient in pyridoxine

(vitamin B6) affect protein metabolism?

1. B6 deficiency sets up a cascade of events

leading to premature breakdown of lipases.

2. The first step in amino acid catabolism

requires a coenzyme derivative of B6.

3. B6 deficiency is critical to later steps of amino

acid catabolism.4. Pyridoxine is not involved in protein

metabolism.



Why are proteins an impractical source of quick

energy, a “last ditch” source of energy?

1. Proteins are more difficult to break apart thanare carbohydrates or lipids.

2. NH4, a byproduct of protein catabolism, is

toxic.

3. Protein catabolism threatens homeostasis.

4. All of the above are correct.



What consequence(s) is/are the result of a

dietary deficiency of one or more essentialamino acids?

1. Protein deficiency disease. 2. The body produces the missing amino

acids by amination.

3. Protein synthesis comes to a halt.

4. 1 and 3 are correct.



Why does the amount of urea in blood

increase during the postabsorptive state?

1. Protein digestion creates urea. 2. Lipolysis creates urea.

3. Glycolysis creates urea.

4. Glycogenesis creates urea.



If a cell accumulates more acetyl-CoA than it

can metabolize by way of the TCA cycle, whichof the following products will form?

1. Ketone bodies

2. Uric acid crystals

3. Lactic acid molecules

4. ATP molecules



Why do athletes in intensive training try to

maintain a positive nitrogen balance?

1. They must excrete more N than they take in.

2. They must keep the amount of N absorbed in

balance with what is lost in urine and feces.

3. They actively synthesize N compounds, so

must absorb more than they secrete.4. None of the above is correct.



Which vitamins is your body capable of

synthesizing?

1. Vitamins D and K

2. Vitamins B12 and C

3. Vitamins A and E

4. Vitamins B6 and C



Why does hypervitaminosis more commonly

involve fat-soluble vitamins?

1. Water-soluble vitamins rapidly degenerate into

their component parts. 2. Excess fat-soluble vitamins are stored in body

lipids.

3. Fat-soluble vitamins participate in more

important reactions than do water-soluble

vitamins.

4. All of the above are true.



How does a decrease in the amount of bile salts in

the bile affect the amount of vitamin A in the body?

1. It would increase vitamin A.

2. It would decrease vitamin A.

3. It would have no effect, since the two

are not related.4. It depends on the absorptive state.



Why is the catabolism of dietary carbohydrates

and proteins considered “not as productive” ascatabolism of lipids?

1. In lipids, many carbon and hydrogen atoms

are already bound to oxygen.

2. Digestion of dietary protein creates toxins.

3. Lipids release almost twice the energy of

proteins or carbohydrates.4. Carbohydrates and proteins have fewer

health benefits than lipids.



How would the BMR of a pregnant woman

compare with her own BMR before she became

pregnant?

1. Higher when pregnant

2. Lower when pregnant

3. No difference during pregnancy

4. It depends on her pre-pregnancy weight



What effect does vasoconstriction of peripheral

blood vessels have on an individual’s bodytemperature on a hot day?

1. An increase in body temperature

2. A decrease in body temperature

3. No difference

4. It depends on the individual’s hydrationlevel



In cold conditions, how does blood flow change

to restrict heat loss?

1. Blood is diverted to the skin to decrease surface

to volume ratio.2. Heat transfer from warm blood in arteries

warms cooler venous blood.

3. Blood flows through the superficial venous

network.

4. Vasomotor centers are inhibited and respiration

increases in depth.



Why do infants have greater problems with

thermoregulation than adults do?

1. Higher surface to volume ratio 2. Undeveloped temperature regulation

3. Expend more energy to remain warm

4. All of the above are correct

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