Cerebral Blood Flow, Cerebrospinal Fluid, and Brain Metabolism
50 questions available
Questions
What is the amount of free energy liberated by the complete oxidation of one mole (180 grams) of glucose?
View answer and explanationUnder the usual physiological conditions of temperature and reactant concentrations, how much energy is liberated by the removal of each of the last two phosphate radicals from an ATP molecule?
View answer and explanationWhat are the three chemical components that combine to form adenosine triphosphate (ATP)?
View answer and explanationGlucose represents, on average, what percentage of the final products of carbohydrate digestion in the alimentary tract?
View answer and explanationWhich enzyme, present in large amounts in liver cells, allows glucose-6-phosphate to be converted back to glucose and released into the blood?
View answer and explanationWhat is the primary mechanism for glucose transport through the membranes of most tissue cells, such as muscle and adipose cells?
View answer and explanationWith the exception of liver and brain cells, the amount of glucose that can diffuse into most body cells in the absence of insulin is sufficient for what?
View answer and explanationWhat percentage of their weight can muscle cells store as glycogen?
View answer and explanationWhat is the name of the process that breaks down the cell's stored glycogen to re-form glucose in the cells?
View answer and explanationWhich two hormones can activate the enzyme phosphorylase to cause rapid glycogenolysis?
View answer and explanationWhat is the net gain in ATP molecules from the entire glycolytic process for each molecule of glucose utilized?
View answer and explanationWhat is the overall efficiency of ATP formation during glycolysis, representing the percentage of energy from the original glucose that is captured in ATP?
View answer and explanationIn which part of the cell does the Citric Acid Cycle (Krebs Cycle) take place?
View answer and explanationFor each molecule of glucose that is metabolized, how many molecules of ATP are formed directly within the Citric Acid Cycle itself?
View answer and explanationApproximately what percentage of the total ATP created through glucose metabolism is formed during the process of oxidative phosphorylation?
View answer and explanationWhat is the total number of hydrogen atoms released for each original molecule of glucose during glycolysis, formation of acetyl-CoA, and the citric acid cycle?
View answer and explanationThe chemiosmotic mechanism for forming ATP occurs entirely within which cellular organelle?
View answer and explanationWhat is the maximum number of ATP molecules that can be formed from the complete degradation of one molecule of glucose to carbon dioxide and water?
View answer and explanationWhat is the overall maximum efficiency of energy transfer when converting the energy from one molecule of glucose into ATP?
View answer and explanationExcess cellular ATP controls energy metabolism by inhibiting which key enzyme in the glycolytic pathway?
View answer and explanationIn addition to ATP, what ion formed in the citric acid cycle also strongly inhibits the enzyme phosphofructokinase?
View answer and explanationAnaerobic glycolysis is described as being extremely wasteful of glucose because it only uses about what percentage of the total energy in the glucose molecule to form ATP?
View answer and explanationUnder anaerobic conditions, the major portion of pyruvic acid is converted into what substance to allow glycolysis to continue?
View answer and explanationWhich tissue in the body is especially capable of converting lactic acid back to pyruvic acid and using it for energy, particularly during heavy exercise?
View answer and explanationWhat is the name of the second important mechanism for the breakdown and oxidation of glucose, which is responsible for as much as 30 percent of glucose breakdown in the liver?
View answer and explanationThe hydrogen released during the pentose phosphate pathway combines with which molecule, which is significant for its role in fat synthesis?
View answer and explanationWhen the body's carbohydrate stores decrease below normal, what is the process of forming glucose from amino acids and the glycerol portion of fat called?
View answer and explanationApproximately what percentage of the amino acids in the body proteins can be easily converted into carbohydrates?
View answer and explanationDuring fasting, approximately what percentage of the liver's glucose production comes from gluconeogenesis?
View answer and explanationWhich hormone, secreted by the adrenal cortex, is especially important for promoting gluconeogenesis by mobilizing proteins from body cells?
View answer and explanationWhat is considered the normal blood glucose concentration in a person who has not eaten a meal within the past 3 to 4 hours?
View answer and explanationAfter a meal containing large amounts of carbohydrates, the blood glucose level in a person without diabetes mellitus seldom rises above what concentration?
View answer and explanationWhat is the term for the process where chemical reactions in cells are linked with physiological systems to provide energy for functions like muscle activity and glandular secretion?
View answer and explanationWhat happens to fructose and galactose after they are absorbed from the intestinal tract?
View answer and explanationWhat is the reason that storing large quantities of carbohydrates as glycogen does not significantly alter the osmotic pressure of intracellular fluids?
View answer and explanationWhat is the initial effect of both epinephrine and glucagon that leads to the activation of phosphorylase?
View answer and explanationDuring glycolysis, glucose is first converted into fructose-1,6-diphosphate and then split into two molecules of what three-carbon compound?
View answer and explanationThe conversion of two pyruvic acid molecules into two molecules of acetyl-CoA releases how many hydrogen atoms?
View answer and explanationWhat is the principal function of the early stages of glucose degradation, such as glycolysis and the citric acid cycle?
View answer and explanationIn the chemiosmotic mechanism, the energy from the electron transport chain is used to do what?
View answer and explanationThe enzyme ATP synthase uses the energy from what process to convert ADP into ATP?
View answer and explanationHow many ATP molecules are produced for every two hydrogen atoms that are released by their dehydrogenase beyond the first stage of the chemiosmotic oxidative schema?
View answer and explanationWhat happens to the excess pyruvic acid and hydrogen atoms when their quantities build up during anaerobic glycolysis?
View answer and explanationThe pentose phosphate pathway is especially important because it can provide energy independently of all the enzymes of which other pathway?
View answer and explanationGlucose is preferentially stored as glycogen until the cells have stored an amount sufficient to supply the energy needs of the body for how long?
View answer and explanationAfter the glycogen-storing cells are saturated, what happens to additional excess glucose?
View answer and explanationWhat are the basic stimuli that increase the rate of gluconeogenesis?
View answer and explanationBy how much can insulin increase the rate of glucose transport into most cells compared to when no insulin is secreted?
View answer and explanationDuring the conversion of pyruvic acid to acetyl-CoA, what vitamin derivative is required to form the coenzyme A portion?
View answer and explanationWhat is the net reaction for the entire glycolytic process per molecule of glucose?
View answer and explanation