Biochem - Metabolism (Part 3) Flashcards Preview

Insulin binds to what type of receptor to activate protein phosphatase, which goes on to inactivate glycogen phosphorylase kinase and glycogen phosphorylase?

An activated glycogen phosphorylase will begin what process?

During glycogen metabolism, glucose-1-phosphate is converted to UDP-glucose by which enzyme?

During glucose metabolism, UDP-glucose is converted to the storage form of glycogen by which enzyme?

In which organ does glycogen undergo rapid glycogenolysis during exercise?

In which organ does glycogen undergo glycogenolysis to maintain blood sugar within an appropriate range?

What type of bond is found at glycogen branch points?

What type of bond is found at side-by-side linkages of glucose in glycogen?

What enzyme creates a new branch point when assembling glycogen molecules?

What enzyme digests glycogen to create a limit dextran?

Once a limit dextran has been created, what enzyme is necessary for further digestion of the glycogen molecule?

Glycogen digestion in the lysosome occurs through which enzyme?

What molecules are the end products of glycogenolysis?

What conversion must occur for the glucose-1-phosphate produced during glycogenolysis to be converted to glucose?

Which enzyme reacts with a limit dextran (four glucose residues in branched configuration) during degradation of glycogen to form glucose?

Which enzyme is responsible for the conversion of glucose-1-phosphate to glucose-6-phosphate?

Which enzyme degrades glycogen to glucose in the lysosome?

Glycogen storage diseases involve an abnormal accumulation of toxic levels of what substance within cells?

How many types of glycogen storage diseases are there?

What is another name for glycogen storage disease type I?

A patient has severe fasting hypoglycemia, increased stores of glycogen in the liver, hepatomegaly, and elevated levels of lactate in his blood. What is the likely underlying metabolic deficiency?

Glycogen storage disease type I results from a deficiency of what enzyme?

What is the prognosis for a child diagnosed with Pompe disease?

Name four glycogen storage diseases.

How can you differentiate between a patient with Cori’s disease and one with von Gierke’s disease using blood samples?

What is another name for glycogen storage disease type II?

In a patient with McArdle’s disease, would you expect increased or decreased levels of glycogen on muscle biopsy?

What is another name for -1,4-glucosidase?

What disease is the result of a deficiency of lysosomal -1,4-glucosidase?

Pompe;s disease (glycogen storage disease type II) is associated with the enlargement of what organ?

Name three organs affected in Pompe’s disease.

What is another name for glycogen storage disease type III?

What is another name for -1,6-glucosidase?

What disease is the result of a deficiency of -1,6-glucosidase?

What is another name for glycogen storage disease type V?

What disease is the result of a deficiency of skeletal muscle glycogen phosphorylase?

A patient has painful cramping and myoglobinuria associated with strenuous exercise. What is the likely underlying metabolic deficiency?

What bodily fluid can be used to diagnose McArdle’s in a patient with severe muscle cramping after exercise?

What enzyme deficiency is seen in Fabry’s disease?

A patient presents with progressive neurodegeneration, hepatosplenomegaly, and a cherry-red spot on his macula. Histologic examination reveals cells containing lipid droplets, confirming a lysosomal storage disease. What are these cells called?

A patient presents with peripheral neuropathy, developmental delay, and optic atrophy. Histologic examination reveals multinucleated macrophages, confirming your diagnosis of a lysosomal storage disease. What are these cells called?

A deficiency of the enzyme -galactosidase A leads to what disease?

What substrate is accumulated in Fabry’s disease?

What type of inheritance does Fabry’s disease demonstrate?

What is the appearance of the cells that may serve as histologic confirmation of Gaucher’s disease?

Name two mucopolysaccharidoses.

A patient shows milder symptoms and appearance similar to Hurler’s syndrome but no corneal clouding; what kind of behavior patterns do you expect?

A patient has peripheral neuropathy of the hands and feet, angiokeratomas of the skin, and both cardiovascular and renal disease. These characteristics are typical of which lysosomal storage disease?

What substrate accumulates in a patient with a deficiency of -glucocerebrosidase?

Name six types of sphingolipidosis.

What substrate is accumulated in Niemann-Pick disease?

What enzyme deficiency leads to Gaucher’s disease?

A child has progressive neurodegeneration, developmental delay, cherry-red spots on the macula, and lysosomes with onion skinning; he does not have hepatomegaly. These characteristics are typical of which lysosomal storage disease?

What is the most common lysosomal storage disorder?

A patient has developmental delay, gargoylism, airway narrowing, and corneal clouding. These characteristics are typical of which lysosomal storage disease?

Which three lysosomal storage disorders are Ashkenazi Jews at increased risk for?

What type of inheritance does Gaucher’s disease demonstrate?

A patient has hepatosplenomegaly, aseptic necrosis of the femur, and abnormal macrophages on histologic examination. These characteristics are typical of which lysosomal storage disease?

What is the term for macrophages that look like crumpled tissue paper under the microscope and are associated with a lysosomal storage disease?

What enzyme deficiency leads to Niemann-Pick disease?

A deficiency of the enzyme sphingomyelinase leads to what disease?

What type of inheritance does Niemann-Pick disease demonstrate?

A child has progressive neurodegeneration, hepatosplenomegaly, and a cherry-red spot on his macula. These characteristics are typical of which lysosomal storage disease?

What enzyme deficiency leads to Tay-Sachs disease?

What substrate is accumulated in Tay-Sachs disease?

What type of inheritance does Tay-Sachs disease demonstrate?

Name two lysosomal storage diseases that may present with a cherry-red spot on the macula.

What enzyme deficiency leads to Krabbe’s disease?

What substrate is accumulated in Krabbe’s disease?

What type of inheritance does Krabbe’s disease demonstrate?

A patient has peripheral neuropathy, developmental delay, and optic atrophy. These characteristics are typical of which lysosomal storage disease?

What enzyme deficiency leads to metachromatic leukodystrophy?

What substrate is accumulated in metachromatic leukodystrophy?

What type of inheritance does metachromatic leukodystrophy demonstrate?

A patient has central and peripheral demyelination with ataxia and dementia. These characteristics are typical of which lysosomal storage disease?

What enzyme deficiency leads to Hurler’s syndrome?

What substrates accumulates in Hurler’s syndrome?

What pattern of inheritance does Hurler’s syndrome demonstrate?

What enzyme deficiency leads to Hunter’s syndrome?

What substrates are accumulated in Hunter’s syndrome?

What pattern of inheritance does Hunter’s syndrome demonstrate?

A patient has mild developmental delay, gargoylism, and airway obstruction but no corneal clouding. These characteristics are typical of which lysosomal storage disease?

Name the two lysosomal storage diseases that lead to an accumulation of heparan sulfate and dermatan sulfate.

Name the two lysosomal storage diseases that show x-linked recessive inheritance.

What is the name of the shuttle that moves acetyl coenzyme A from the mitochondria to the cytoplasm to participate in fatty acid synthesis?

The addition of carbon dioxide to acetyl coenzyme A during fatty acid synthesis yields what molecule?

In acyl-CoA dehydrogenase deficiency, dicarboxylic acid levels _____ (increase/decrease) and glucose and ketone levels _____ (increase/decrease).

A deficiency of which enzyme in fatty acid metabolism causes an increase in dicarboxylic acids and a decrease in glucose and ketones?

What cofactor is required for the conversion of acetyl-CoA to malonyl-CoA during fatty acid synthesis?

Where does fatty acid degradation occur? Where are the products of degradation consumed?

What is the name of the shuttle that moves long-chain fatty acids from the cytoplasm to the mitochondria to participate in fatty acid degradation?

After breakdown of fatty acids, the resulting acetyl-CoA groups can be put to which uses?

In which direction does the citrate shuttle move acetyl-CoA across the mitochondrial membrane?

In which direction does the carnitine shuttle move fatty acids across the mitochondrial membrane?

A deficiency of what substance will result in hypoketotic hypoglycemia?

What are the clinical sequelae of carnitine deficiency?

Name two ketone bodies derived from acetyl-CoA. (These are found in individuals who have experienced prolonged starvation and diabetic ketoacidosis.)

In a patient with high levels of circulating ketone bodies, what does the breath smell like?

Which two precursors can be made into ketone bodies?

What is the precursor molecule to acetoacetate?

In alcoholism, the citric acid cycle is stalled due to excess NADH, causing a shunting of glucose and free fatty acids toward formation of _______ _______.

Which two organs can use ketone bodies as fuel during starvation?

Which ketone body cannot be detected by a urine test?

A patient with a history of alcoholism presents to the emergency department intoxicated. Excess NADH and the shunting of oxaloacetate to malate may result in finding what substance in his urine?

Where in the body are ketones synthesized?

In which two pathological states will the body produce large amounts of ketones?

The brain can convert one ketone body into two of what type of molecule?

1 gram protein or carbohydrate = ____ kcal

1 gram fat = ___ kcal

During the first three days of fasting, which four processes maintain the blood glucose level?

What molecules do skeletal muscles contribute for hepatic gluconeogenesis in order to maintain the blood glucose level?

What are the only triacylglycerol molecules that can contribute to gluconeogenesis?

Which compounds do adipose tissues contribute for hepatic gluconeogenesis in order to maintain the blood glucose level during the first three days of starvation?

What two metabolic processes does the liver undergo to maintain blood glucose level in the first three days of fasting/starvation?

Name the organ: After the third day of fasting, ketone bodies formed in the _____ supply the _____ and the ______ with energy.

What role does adipose tissue play in maintaining blood glucose levels in the first three days of fasting/starvation?

Which tissues contribute the compounds required for hepatic gluconeogensis in order to maintain the blood glucose level during the first three days of fasting?

True or False? More muscle protein is degraded during days 1-3 of starvation than after several weeks of starvation.

After several weeks of starvation, survival time is determined by the amount of _____ (muscle/fat) stores.

Once fat stores are depleted after several weeks of starvation, _____ (protein/glucose/free fatty acid) degradation accelerates, leading to organ failure and death.

What are the sources of adenosine triphosphate for muscles during brief exercise?

In addition to the sources that can be used in seconds, from which sources do muscles derive adenosine triphosphate during exercise that lasts at least several minutes?

Which sources of adenosine triphosphate does the body use during exercise that lasts for hours?

What are the purposes of the metabolic changes the body undergoes during starvation?

What is the enzyme that esterifies plasma cholesterol?

What category of drugs inhibits HMG coenzyme A reductase?

What enzyme catalyzes the rate-limiting reaction in cholesterol synthesis?

What are the two essential fatty acids?

What acid becomes essential in the absence of linoleic acid?

The formation of eicosanoids is dependent on the consumption of which fatty acids?

Which enzyme is responsible for the degradation of dietary triglycerides?

Which enzyme is responsible for the degradation of triglycerides that are circulating as chylomicrons?

Which organs take up low-density lipoproteins from the circulation?

Which enzyme is responsible for the degradation of triglycerides circulating as intermediate-density lipoproteins?

What is the enzyme responsible for converting nascent high-density lipoproteins into mature high-density lipoproteins?

What enzyme is responsible for the degradation of triglycerides that are stored within adipocytes?

What enzyme transfers cholesterol esters from high-density lipoproteins to other lipoproteins?

What organ releases chylomicrons into the circulation?

Name three lipoproteins that receive cholesterol esters from high-density lipoprotein via cholesteryl ester transfer protein.

What enzyme converts chylomicrons into chylomicron remnants?

What organ takes up chylomicron remnants from the circulation?

What organ releases very-low-density lipoprotein into the circulation?

What enzymes convert intermediate-density lipoproteins into low-density lipoproteins?

What enzyme converts very-low-density lipoproteins into intermediate-density lipoproteins?

Which apolipoprotein activates lecithin-cholesterol acyltransferase?

Which apolipoprotein binds to the low-density lipoprotein receptor on the liver?

What apolipoprotein mediates very-low-density lipoprotein secretion?

Which apolipoprotein acts as a cofactor for lipoprotein lipase?

Which apolipoprotein mediates remnant uptake?

What molecules do lipoproteins contain?

Which lipoprotein delivers dietary triglycerides to peripheral tissues?

Which lipoprotein is secreted only by intestinal epithelial cells?

Which apolipoprotein mediates the secretion of chylomicrons from the gastrointestinal tract?

Which lipoprotein delivers hepatic triglycerides to peripheral tissues?

Which organ secretes very-low-density lipoprotein into the bloodstream?

Name the two major lipoprotein carriers of cholesterol

What lipoprotein carries cholesterol from the liver to the tissues?

What lipoprotein carries cholesterol from the tissues to the liver?

Which apolipoprotein on low-density lipoprotein mediates uptake into the liver?

Which lipoprotein delivers dietary cholesterol to the liver?

Which lipoprotein mediates the transport of cholesterol from the periphery to the liver (reverse transport)?

Name four apolipoproteins found on chylomicrons.

Which lipoprotein acts as a reservoir of apolipoprotein C and apolipoprotein E?

Which lipoprotein is formed by the degradation of very-low-density lipoprotein in the periphery by lipoprotein lipase (via IDL as an intermediate)?

What three apolipoproteins are found on very-low-density lipoprotein?

Which lipoprotein is formed by the degradation of very-low-density lipoprotein?

What lipoprotein is secreted by both intestinal epithelial cells and the liver?

Which lipoprotein delivers triglycerides and cholesterol to the liver for degradation into low-density lipoprotein?

What are the two apolipoproteins found on intermediate-density lipoprotein?

What is another name for type I dyslipidemia?

An altered apolipoprotein C-II that does not function properly produces which type of familial dyslipidemia?