Practice Questions Flashcards
What is the major contributor to lipid bilayer self assembly?
A. Van der waals forces
B. Electrostatic interactions
C. Hydrophobic interactions
D. Hydrogen bonds
C. Hydrophobic interactions
What of the following modifications would result in the formation of a thioester bond involving a specific amino acid?
A. Palmitoylation of cysteine residues
B. Palmitoylation of aspartate residues
C. Farnesylation of cysteine residues
D. Farnesylation of aspartate residues
A. Palmitoylation of cysteine residues
What is the site of most of the TCA cycle and fatty acid oxidation in the mitochondria?
A. Intermembrane space
B. Inner membrane
C. Outer membrane
D. Matrix
D. Matrix
Which of the following fuels has the lowest caloric content?
A. Carbs
B. Fats
C. Alcohols
D. Lipids
A. Carbs
Essential amino acids are very crucial for maintaining health; if not taking them sufficiently in the diet, a person would have a _____________
A. Positive nitrogen balance
B. Positive phosphorus balance
C. Negative nitrogen balance
D. Negative phosphorus balance
C. Negative nitrogen balance
Glucose and fructose are monosaccharides that make up which disaccharide?
A. Lactose
B. Maltose
C. Ribose
D. Sucrose
D. Sucrose
Which of the following is one of the most biologically active minerals required in the diet?
A. Iodine
B. Chloride
C. Manganese
D. Molybdenum
B. Chloride
Which of the following is a purine base?
A. Thymine
B. Inosine
C. Adenosine
D. Hypoxanthine
D. Hypoxanthine
Place the required enzymes in order for the digestion of DNA when starting with a long DNA chain
A. Nucleotidase, nucleosidase, phosphodiesterase, deoxyribonuclease
B. Deoxyribonuclease, phosphodiesterase, nucleotidase, nucleosidase
C. Phosphodiesterase, nucleotidase, nucleosidase, deoxyribonuclease
D. Deoxyribonuclease, nucleotidase, nucleosidase, phosphodiesterase
B. Deoxyribonuclease, phosphodiesterase, nucleotidase, nucleosidase
What are the primary regulatory mechanisms involved in the committed step of de novo purine nucleotide synthesis?
A. PRPP stimulates, purine nucleotides inhibit
B. Purine nucleotides stimulate, PRPP inhibits
C. Phosphate stimulates, purine nucleotides inhibit
D. Purine nucleotides stimulate, phosphate inhibits
A. PRPP stimulates, purine nucleotides inhibit
What occurs during the committed step of de novo purine nucleotide synthesis?
A. Addition of amino group to PRPP
B. Cleavage of phosphate group off of PRPP
C. Addition of carbonyl group to PRPP
D. Opening of the PRPP ring
A. Addition of amino group to PRPP
Regarding nucleotide metabolism, what is the likely state of the synthesized nucleotide if the body is in a state of fasting?
A. Monophosphate form
B. Triphosphate form
C. Diphosphate form
D. Tetraphosphate form
B. Triphosphate form
What would be a likely consequence of a dysfunction of UMP synthase?
A. Buildup of UMP
B. Buildup of CDP
C. Buildup of orotate
D. Buildup of carbamoyl aspartate
C. Buildup of orotate
Adenine phosphoribosyl-transferase is an important enzyme utilized in which of the following pathways?
A. Pyrimidine nucleotide salvage
B. De novo purine syntheis
C. De novo pyrimidine synthesis
D. Purine nucleotide salvage
D. Purine nucleotide salvage
Which of the following glucose transporters is insulin-dependent?
A. GLUT1
B. GLUT2
C. GLUT3
D. GLUT4
D. GLUT4
In what state is glucose considered “trapped” in the cell, at which time the only organ that can convert it to free glucose is the liver?
A. Glucose 6-phosphate
B. Glucose 1-phosphate
C. Glucose 2,6 bisphosphate
D. Glucose 3-phosphate
A. Glucose 6-phosphate
What are the primary regulators of phosphofructokinase?
A. Inhibition by F-2,6-BP activation by citrate
B. Inhibition by hexokinase, activated by citrate
C. Inhibition by pyruvate kinase, activation by F-2,6-BP
D. Inhibition by citrate, activation by F-2,6-BP
D. Inhibition by citrate, activation by F-2,6-BP
What are two necessary enzymes needed to get from pyruvate to glyceraldehyde 3-phosphate in gluconeogenesis?
A. Pyruvate carboxylase and phosphoenolpyruvate kinase via bypass reaction
B. Pyruvate kinase and phosphoenolpyruvate kinase via bypass reaction
C. Pyruvate carboxylase and phosphoenolpyruvate kinase via direct reaction
D. Pyruvate kinase and enolase via bypass reaction
A. Pyruvate carboxylase and phosphoenolpyruvate kinase via bypass reaction
Which of the following is not an enzyme involved in an irreversible reaction of glycolysis in the liver?
A. Glucokinase
B. Pyruvate kinase
C. G3P dehydrogenase
D. Phosphofructokinase
C. G3P dehydrogenase
Which of the following is/are positive regulator(s) of glycolysis?
A. Citrate B. AMP C. F-2,6-BP D. B and C E. None of the above
D. B and C
What effect would high AMP levels have on glycogen phosphorylase in the liver?
A. The phosphorylase would be activated due to low energy charge
B. The phosphorylase would be inactivated due to low energy charge
C. The phosphorylase would be inactivated due to high energy charge
D. The phosphorylase would not respond to changes in AMP levels
D. The phosphorylase would not respond to changes in AMP levels
What effect does branching of glycogen chains have on the molecules?
A. Increases solubility and increases rate of synthesis/degradation
B. Decreases solubility but increases rate of synthesis/degradation
C. Increases solubility but decreases rate of synthesis/degradation
D. Decreases solubility and decreases rate of synthesis/degradation
A. Increases solubility and increases rate of synthesis/degradation
Phosphorylation of glycogen synthase kinase would have what effect on glycogenesis?
A. Activation of glycogen synthase, thus promoting the syntehsis of glycogen
B. Inactivation of glycogen synthase, thus inhibiting the synthesis of glycogen
C. Activation of glycogen phosphorylase, thus promoting the synthesis of glycogen
D. Inactivation of glycogen phosphorylase, thus inhibiting the synthesis of glycogen
B. Inactivation of glycogen synthase, thus inhibiting the synthesis of glycogen
Amylopectin differs from amylose in what way?
A. It is considered a starch
B. It is linear
C. It is branched
D. It has (alpha) 1,4-glycosidic linkages
C. It is branched