E08 - MCQ

Which factor would coordinate a decrease in the rates of glycolysis in in the liver?

• epinephrine

• insulin

• glucagon

• high ADP and NAD⁺ concentrations

• increased levels of pyruvate and acetyl-CoA

How is liver glucokinase (hexokinase IV) different than other hexokinases in other tissues? Indicate all correct answers.

• Glucokinase has a much higher Km.

• Glucokinase requires ATP and NADH for its activity

• Glucokinase is not feedback inhibited by glucose-6-phosphate

• Because of high Km, phosphorylation of glucose is low when the plasma concentration of glucose is low, maintaining plasma glucose levels

• None of the answers is correct

Insulin promotes many metabolic effects in different tissues. Which statement is TRUE?

• In the liver, insulin promotes glycolysis, glycogenesis but decreases fatty acid synthesis.

• In the liver, insulin promotes glycolysis and glycogenesis but increases fatty acid synthesis.

• In the adipose tissue, insulin promotes glycolysis and glycogenesis.

• In the muscle, insulin promotes glycogenolysis and gluconeogenesis.

• In the adipose tissue, insulin inhibits glycolysis and glycogenesis.

Very active muscles use glycogen (anaerobically) as energy source, generating lactate via fermentation.

• Lactate is transported to the liver and converted to glucose via gluconeogenesis.

• Lactate is transported to the liver and converted to glycogen via gluconeogenesis.

• Lactate remains in muscles and is converted to creatine by creatine kinase.

• Lactate remains in muscles and is converted to creatine by creatine phosphatase.

• Lactate is transported to the liver and converted to fatty acids via fatty acids synthesis.

During fasting glucagon level is high, it acts to

• Maintain stable glycogen levels in liver

• Maintain stable glucose levels

• Maintain stable glucose levels and prevents lipolysis in adipose tissue

• Maintain stable production of lactic acid in muscles and increases lipolysis in adipose tissue

• Maintain stable levels of Malonyl-CoA synthesis in adipose tissue

Uncontrolled type 1 diabetes can lead to a life-threatening complication called diabetic ketoacidosis. Ketone bodies are being produced to provide the brain with energy. Which organ or cells produce ketone bodies?

• Brain

• Pancreas

• Muscle

• Intestine

• Liver

Blood glucose level is relatively constant across the day. In response to food intake and increased blood glucose levels insulin is secreted from islets of Langerhans in the pancreas. Which of the statements is correct?

• In adipocytes, insulin promotes release of glucagon and inhibition of fatty acid synthesis

• In muscle, insulin facilitates glucose uptake

• In the liver, insulin promotes synthesis of ketone bodies.

• In muscle, insulin facilitates production of lactic acid

• In brain, insulin stimulated release of triacylglycerol and unsaturated lipids

Normal human blood sugar determined using fasting blood glucose test should be in a arrange of

• 150 to 180 mg/dL

• 8.2 - 10.1 mmol/L

• 2.2 - 4.1 mmol/L

• 4.4 - 6.1 mmol/L

• 250 to 380 mg/dL