Transcript Chapter 25 - FacultyWeb

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.
2.
3.
4.
Break down glucose
Create hydrogen gradient
Phosphorylate ADP
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 ATP
molecules.
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 gradient
across 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 in
cardiac muscle cells leads to production of three ATP
molecules. Why?
1.
2.
3.
4.
Different systems
Different pH
Different intermediaries
More efficient enzymes in cardiac
muscle
How does a decrease in the level of cytoplasmic
NAD affect ATP production in mitochondria?
1.
2.
3.
4.
ATP production increases.
ATP production decreases.
Pyruvic acid supplies increase.
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.
2.
3.
4.
They increase lipid metabolism.
They decrease blood pressure.
They increase blood pH.
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) is
created.
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 than
are 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 process in the liver increases after you
have eaten a high-carbohydrate meal?
1.
2.
3.
4.
Glycolysis
Glycogenesis
Lipolysis
Beta-oxidation
What consequence(s) is/are the result of a
dietary deficiency of one or more essential
amino 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.
2.
3.
4.
Protein digestion creates urea.
Lipolysis creates urea.
Glycolysis creates urea.
Glycogenesis creates urea.
If a cell accumulates more acetyl-CoA than it
can metabolize by way of the TCA cycle, which
of the following products will form?
1.
2.
3.
4.
Ketone bodies
Uric acid crystals
Lactic acid molecules
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.
2.
3.
4.
Vitamins D and K
Vitamins B12 and C
Vitamins A and E
Vitamins B6 and C
Why does hypervitaminosis more commonly
involve fat-soluble vitamins?
1.
2.
3.
4.
Water-soluble vitamins rapidly degenerate into
their component parts.
Excess fat-soluble vitamins are stored in body
lipids.
Fat-soluble vitamins participate in more
important reactions than do water-soluble
vitamins.
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” as
catabolism 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.
2.
3.
4.
Higher when pregnant
Lower when pregnant
No difference during pregnancy
It depends on her pre-pregnancy weight
What effect does vasoconstriction of peripheral
blood vessels have on an individual’s body
temperature on a hot day?
1.
2.
3.
4.
An increase in body temperature
A decrease in body temperature
No difference
It depends on the individual’s hydration
level
In cold conditions, how does blood flow change
to restrict heat loss?
1.
2.
3.
4.
Blood is diverted to the skin to decrease surface
to volume ratio.
Heat transfer from warm blood in arteries
warms cooler venous blood.
Blood flows through the superficial venous
network.
Vasomotor centers are inhibited and respiration
increases in depth.
Why do infants have greater problems with
thermoregulation than adults do?
1.
2.
3.
4.
Higher surface to volume ratio
Undeveloped temperature regulation
Expend more energy to remain warm
All of the above are correct