836 - 863 Carbohydrate metabolism Flashcards
Identify the missing ‘S’ intermediate
Select one:
a. Glucose
b. Galactose
c. Fucose
d. Glucose-1-phosphate
e. 1,3-bisphosphoglycerate
a. Glucose
Identify the missing ‘S’ intermediate.
Select one:
a. Glucose-6-phosphate
b. Glucose-1-phosphate
c. Galactolactone
d. Glucose-3-phosphate
e. 3-phosphoglycerate
a. Glucose-6-phosphate
Identify the missing ‘S’ intermediate.
Select one:
a. 6-Phosphogluconolactone
b. Glucose-1-phosphate
c. Glyceraldehyde
d. 1-phosphogluconolactone
e. 6-hydroxy-gluconolactone
a. 6-Phosphogluconolactone
Identify the missing ‘X’ cofactor.
Select one:
a. ATP, Mg2+
b. AMP, Mg2+
c. PPi, Mg2+
d. NAD
e. FAD
a. ATP, Mg2+
Identify the missing ‘X’ cofactor.
Select one:
a. ADP, Mg2+
b. ATP, Mg2+
c. AMP, Mg2+
d. NADPH + H
e. FAD
a. ADP, Mg2+
Identify the missing ‘X’ cofactor.
Select one:
a. NADP+
b. ATP
c. ADP
d. FADH + H+
e. NADH
a. NADP+
Identify the missing ‘X’ cofactor.
Select one:
a. NADPH + H+
b. ATP, Mg2+
c. ADP, Mg2+
d. NADH + H+
e. Glucose
a. NADPH + H+
Identify the missing ‘E’ enzyme.
Select one:
a. Hexokinase
b. Phosphatase
c. Lactone kinase
d. Hexophosphorylase
e. Phosphokinase
a. Hexokinase
Identify the missing ‘E’ enzyme.
Select one:
a. Glucose-6-phosphate dehydrogenase
b. Glucose-3-phosphate dehydrogenase c
. Glucose-6-phosphate deacetylase
d. Hexophosphatase
e. Pyruvate kinase
a. Glucose-6-phosphate dehydrogenase
Which of the following is a definition of glycemic index?
Select one:
a. The decrease in the blood concentration of glucagon after consuming the food compared with an equivalent amount
of white bread.
b. The increase in the blood concentration of glucose after
consuming the food.
c. The increase in the blood concentration of glucose after
consuming the food compared with an equivalent amount of white bread.
d. The increase in the blood concentration of insulin after
consuming the food.
e. The increase in the blood concentration of insulin after
consuming the food compared with an equivalent amount of white bread.
c. The increase in the blood concentration of glucose after consuming the food compared with an equivalent amount of white bread.
Which of the following will have the lowest glycemic index?
Select one:
a. baked apple
b. A baked potato
c. An uncooked apple
d. An uncooked potato
e. Apple juice
d. An uncooked potato
Which of the following will have the highest glycaemic index?
Select one:
a. A baked apple
b. A baked potato
c. An uncooked apple
d. An uncooked potato
e. Apple juice
e. Apple juice
A blood sample is taken from a 50-year-old woman after an overnight fast. Which one of the following will be at a higher concentration than after she had eaten a meal?
Select one:
a. Glucose
b. Insulin
c. Ketone bodies
d. Nonesterified fatty acids
e. Triacylglycerol
d. Nonesterified fatty acids
A blood sample is taken from a 25-year-old man after he has eaten three slices of toast and a boiled egg. Which one of the following will be at a higher concentration than if the blood sample had been taken after an overnight fast?
Select one:
a. Alanine
b. Glucagon
c. Glucose
d. Ketone bodies
e. Nonesterified fatty acids
c. Glucose
A blood sample is taken from a 40-year-old man has been fasting completely for a week, drinking only water. Which of the following will be at a higher concentration than after a normal overnight fast?
Select one:
a. Glucose
b. Insulin
c. Ketone bodies
d. Nonesterified fatty acids
e. Triacylglycerol
c. Ketone bodies
Which one of following statements about the fed and fasting metabolic states is correct?
Select one:
a. In the fasting state glucagon acts to increase the activity of lipoprotein lipase in adipose tissue.
b. In the fasting state, glucagon acts to increase the synthesis of glycogen from glucose.
c. In the fed state insulin acts to increase the breakdown of glycogen to maintain blood glucose.
d. Ketone bodies are synthesized in liver in the fasting state, and the amount synthesized increase as fasting extends into starvation.
e. In the fed state there is decreased secretion of insulin in response to increased glucose in the portal blood.
d. Ketone bodies are synthesized in liver in the fasting state, and the amount synthesized increase as fasting extends into starvation.§
Which one of following statements about the fed and fasting metabolic states is correct?
Select one:
a. In the fed state muscle can take up glucose for use as a metabolic fuel because glucose transport in muscle is stimulated in response to glucagon.
b. In the fed state there is decreased secretion of glucagon in response to increased glucose in the portal blood.
c. In the fed state, glucagon acts to increase the synthesis of glycogen from glucose.
d. Plasma glucose is maintained in starvation and prolonged fasting by gluconeogenesis from ketone bodies.
e. There is an increase in metabolic rate in the fasting state.
b. In the fed state there is decreased secretion of glucagon in response to increased glucose in the portal blood.
Which one of following statements about the fed and fasting metabolic states is correct?
Select one:
a. In the fasting state muscle synthesizes glucose from amino acids.
b. In the fed state adipose tissue can take up glucose for synthesis of triacylglycerol because glucose transport in adipose tissue is stimulated in response to insulin.
c. Ketone bodies are synthesized in muscle in the fasting state, and the amount synthesized increases as fasting extends into starvation.
d. Ketone bodies provide an alternative fuel for red blood cells in the fasting state.
e. Plasma glucose is maintained in starvation and prolonged fasting by gluconeogenesis from fatty acids.
b. In the fed state adipose tissue can take up glucose for synthesis of triacylglycerol because glucose transport in adipose tissue is stimulated in response to insulin.
Which one of following statements about the fed and fasting metabolic states is correct?
Select one:
a. In the fasting state adipose tissue synthesizes glucose from
the glycerol released by the breakdown of triacylglycerol.
b. In the fasting state adipose tissue synthesizes ketone bodies.
c. In the fasting state the main fuel for red blood cells is fatty
acids released from adipose tissue.
d. Ketone bodies provide the main fuel for the central nervous
system in the fasting state.
e. Plasma glucose is maintained in starvation and prolonged fasting by gluconeogenesis in the liver from the amino acids released by the breakdown of muscle protein.
e. Plasma glucose is maintained in starvation and prolonged fasting by gluconeogenesis in the liver from the amino acids released by the breakdown of muscle protein.
Which one of following statements about the fed and fasting metabolic states is correct?
Select one:
a. Fatty acids and triacylglycerol are synthesized in the liver in
the fasting state.
b. In the fasting state the main fuel for the central nervous
system is fatty acids released from adipose tissue.
c. In the fasting state the main metabolic fuel for most tissues
comes from fatty acids released from adipose tissue.
d. In the fed state muscle cannot take up glucose for use as a
metabolic fuel because glucose transport in muscle is
stimulated in response to glucagon.
e. Plasma glucose is maintained in starvation and prolonged
fasting by gluconeogenesis in adipose tissue from the glycerol released from triacylglycerol.
c. In the fasting state the main metabolic fuel for most tissues comes from fatty acids released from adipose tissue.
A 25-year-old man visits his GP complaining of abdominal cramps and diarrhea after drinking milk. What is the most likely cause of his problem?
Select one:
a. Bacterial and yeast overgrowth in the large intestine
b. Infection with the intestinal parasite Giardia lamblia
c. Lack of pancreatic amylase
d. Lack of small intestinal lactase
e. Lack of small intestinal sucrase-isomaltase
d. Lack of small intestinal lactase
Which one of following statements about glycolysis and gluconeogenesis is correct?
Select one:
a. All the reactions of glycolysis are freely reversible for
gluconeogenesis.
b. Fructose cannot be used for gluconeogenesis in the liver
because it cannot be phosphorylated to fructose-6-
phosphate.
c. Glycolysis can proceed in the absence of oxygen only if
pyruvate is formed from lactate in muscle.
d. Red blood cells only metabolize glucose by anaerobic
glycolysis (and the pentose phosphate pathway).
e. The reverse of glycolysis is the pathway for gluconeogenesis
in skeletal muscle.
d. Red blood cells only metabolize glucose by anaerobic glycolysis (and the pentose phosphate pathway).
Which one of following statements about the step in glycolysis catalyzed by hexokinase and in gluconeogenesis by glucose 6-phosphatase is correct?
Select one:
a. Because hexokinase has a low Km its activity in liver
increases as the concentration of glucose in the portal
blood increases.
b. Glucose-6-phosphatase is mainly active in muscle in the
fasting state.
c. If hexokinase and glucose-6-phosphatase are both equally
active at the same time there is net formation of ATP from
ADP and phosphate.
d. Liver contains an isoenzyme of hexokinase, glucokinase,
which is especially important in the fed state
e. Muscle can release glucose into the circulation from its
glycogen reserves in the fasting state.
d. Liver contains an isoenzyme of hexokinase, glucokinase, which is especially important in the fed state
Which one of following statements about this step in glycolysis catalyzed by phosphofructokinase and in gluconeogenesis by fructose 1,6-bisphosphatase is correct?
Select one:
a. Fructose 1,6-bisphosphatase is mainly active in the liver in the fed state.
b. If phosphofructokinase and fructose 1,6-bisphosphatase are both equally active at the same time, there is a net formation of ATP from ADP and phosphate.
c. Phosphofructokinase is inhibited more or less completely by physiological concentrations of ATP.
d. Phosphofructokinase is mainly active in the liver in the fasting state.
c. Phosphofructokinase is inhibited more or less completely by physiological concentrations of ATP.
