Nitra Memrizz Multiple Choice Questions PDF

Memrizz Nitra Multiple Choice Questions What is hyperammonemia characterized by? a) Low levels of nitrogen in the blood. b) High levels of ammonia in the blood. c) Normal enzyme levels in the urea cycle. d) Decreased production of urea. Correct answer: High level...

Memrizz Nitra Multiple Choice Questions What is hyperammonemia characterized by? a) Low levels of nitrogen in the blood. b) High levels of ammonia in the blood. c) Normal enzyme levels in the urea cycle. d) Decreased production of urea. Correct answer: High levels of ammonia in the blood. What often causes hyperammonemia? a) Deficiencies in enzymes of the urea cycle. b) Excessive ammonia production. c) High protein diet. d) Increased urea synthesis. Correct answer: Deficiencies in enzymes of the urea cycle. What activates the urea cycle? a) High levels of ammonia. b) Low bicarbonate levels. c) Flow of nitrogen. d) Excess urea. Correct answer: Flow of nitrogen. Which enzyme generates N-Acetylglutamate? a) Ornithine Transcarbamylase. b) N-Acetylglutamate Synthetase. c) Carbamylphosphate Synthetase 1. d) Argininosuccinate Synthetase. Correct answer: N-Acetylglutamate Synthetase. What is the role of N-Acetylglutamate in the urea cycle? a) Inhibits Ornithine Transcarbamylase. b) Decreases nitrogen flow. c) Promotes urea excretion. d) Activates Carbonyl Phosphate Synthetase 1. Correct answer: Activates Carbonyl Phosphate Synthetase 1. What are urea precursors? a) Substances providing nitrogen for the urea cycle. b) Urea byproducts in kidney. c) Hormones regulating metabolism. d) Proteins contributing to energy. Correct answer: Substances providing nitrogen for the urea cycle. Which is the rate-limiting enzyme of the urea cycle? a) Ornithine Transcarbamylase. b) Argininosuccinate Synthetase. c) Arginase. d) Carbamylphosphate Synthetase 1. Correct answer: Carbamylphosphate Synthetase 1. What is the first step in the urea cycle process? a) Formation of Carbamylphosphate. b) Conversion of Citrulline to Argininosuccinate. c) Production of Urea from Arginine. d) Formation of Arginine from Argininosuccinate. Correct answer: Formation of Carbamylphosphate. Which reaction uses the ammonium ion in the urea cycle? a) Ammonium ion + Bicarbonate !’ Carbamylphosphate. b) Citrulline + Urea !’ Arginine. c) Argininosuccinate + Water !’ Citrulline. d) Carbamylphosphate + H2O !’ Urea. Correct answer: Ammonium ion + Bicarbonate !’ Carbamylphosphate. What is produced when Argininosuccinate is converted to Arginine? a) Urea. b) Arginine. c) Citrulline. d) Carbamylphosphate. Correct answer: Arginine. What is the final product of the urea cycle? a) Ammonium. b) Citrulline. c) Urea. d) Arginine. Correct answer: Urea. What role does Alpha Keto Glutarate play in hyperammonemia? a) Acts as a direct ammonia detoxifier. b) Converts urea directly into ammonia. c) Forms glutamate, an intracellular nitrogen carrier. d) Stimulates the urea cycle enzymes. Correct answer: Forms glutamate, an intracellular nitrogen carrier. Where does the urea cycle primarily occur? a) In the kidneys. b) In the liver. c) In the plasma. d) In the mitochondria. Correct answer: In the liver. Which cellular compartment houses the first two urea cycle enzymes? a) Cytosol. b) Mitochondrial matrix. c) Nucleus. d) Cell membrane. Correct answer: Mitochondrial matrix. What is the function of Carbamylphosphate Synthetase 1 (CPS 1)? a) Breaks down ammonia into urea. b) Converts citrulline to ornithine. c) Catalyzes reaction forming carbonyl phosphate. d) Facilitates urea excretion. Correct answer: Catalyzes reaction forming carbonyl phosphate. What is produced by the reaction of ornithine and carbamyl phosphate? a) Glutamate. b) Urea. c) Ammonium ion. d) Citrulline. Correct answer: Citrulline. What role does N Acetylglutamate have in the urea cycle? a) Catalyzes the conversion of urea to ammonia. b) Inhibits enzyme activity in the cycle. c) Acts as a product of the cycle. d) Facilitates the function of CPS 1. Correct answer: Facilitates the function of CPS 1. Why is the urea cycle critical for the body? a) Detoxifies ammonia and maintains nitrogen balance. b) Promotes protein synthesis. c) Regulates blood glucose levels. d) Increases muscle mass. Correct answer: Detoxifies ammonia and maintains nitrogen balance. Where are the first two enzymes of the urea cycle located? a) Cytosol b) Nucleus c) Endoplasmic Reticulum d) Mitochondrial Matrix Correct answer: Mitochondrial Matrix Which enzymes of the urea cycle reside in the cytosol? a) All enzymes b) Only CPS 1 c) Only Arginase d) The remaining three enzymes Correct answer: The remaining three enzymes What does Carbonyl Phosphate Synthetase 1 (CPS 1) produce? a) Carbonyl phosphate b) Citrulline c) Urea d) Arginine Correct answer: Carbonyl phosphate What is a key reactant for CPS 1 in the urea cycle? a) Citrulline b) Bicarbonate c) Ornithine d) Aspartate Correct answer: Bicarbonate What reaction does Ornithine Transcarbamylase catalyze? a) Ornithine and carbamyl phosphate to citrulline b) Citrulline to arginine c) Arginase producing urea d) CPS 1 producing carbonyl phosphate Correct answer: Ornithine and carbamyl phosphate to citrulline What is produced by Arginosuccinate Synthetase? a) Citrulline b) Arginosuccinate c) Urea d) Carbonyl phosphate Correct answer: Arginosuccinate Arginosuccinate Lyase produces which compound? a) Urea b) Citrulline c) Aspartate d) Arginine Correct answer: Arginine What compound does Arginase convert into urea? a) Arginine b) Citrulline c) Ammonium ion d) Aspartate Correct answer: Arginine What condition results from disruptions in the urea cycle? a) Citrullinemia b) Uremia c) Hyperammonemia d) Lactate acidosis Correct answer: Hyperammonemia What does carbonyl phosphate contain at one end? a) An amino group b) A hydroxyl group c) A sulfur group d) A phosphate group Correct answer: A phosphate group What is the significance of carbonyl phosphate in the urea cycle? a) It is a waste product b) It is the final product c) It is an activated form of urea d) It is a nitrogen source Correct answer: It is an activated form of urea What is hyperammonemia? a) Elevated levels of ammonia in the blood. b) Low levels of ammonia in the blood. c) Reduced protein intake in the diet. d) Increased urea production in the liver. Correct answer: Elevated levels of ammonia in the blood. What does decreased carbamylphosphate indicate? a) High levels of ammonia in the blood. b) A reduction in an important urea cycle intermediate. c) Normal urea cycle function. d) Increased protein metabolism. Correct answer: A reduction in an important urea cycle intermediate. How is orotic acid level used in diagnosis? a) As a key diagnostic marker for urea cycle disorders. b) To measure liver function. c) To assess kidney health. d) To evaluate protein intake. Correct answer: As a key diagnostic marker for urea cycle disorders. Which symptom indicates central edema? a) Swelling in the brain due to excess ammonia. b) Fatigue and lethargy. c) Increased heart rate. d) Lowered blood sugar levels. Correct answer: Swelling in the brain due to excess ammonia. What condition can result from severe urea cycle disorders? a) Increased energy levels. b) Coma. c) Enhanced cognitive function. d) Improved metabolic rates. Correct answer: Coma. What characterizes OTC deficiency? a) Decreased ammonia levels. b) Elevated levels of carbamylphosphate. c) Normal orotic acid levels. d) Low levels of carbamylphosphate. Correct answer: Elevated levels of carbamylphosphate. What symptom is associated with CPS 1 deficiency? a) Decreased orotic acid levels. b) Elevated orotic acid levels. c) Severe skin rashes. d) Increased blood pressure. Correct answer: Decreased orotic acid levels. What can ammonium do regarding the blood-brain barrier? a) Cross this barrier, causing central edema. b) Be converted to urea easily. c) Strengthen the blood-brain barrier. d) Be filtered out by the kidneys. Correct answer: Cross this barrier, causing central edema. Orotic acid urea is linked to which urea cycle disorder? a) CPS 1 deficiency. b) OTC deficiency. c) Enzyme overproduction disorder. d) Liver failure syndrome. Correct answer: OTC deficiency. What clinical signs accompany lethargy in urea cycle disorders? a) Increased appetite and hydration. b) Improved motor coordination. c) Elevated mood swings. d) Convulsions and coma. Correct answer: Convulsions and coma. What molecule does Citrulline convert to in the Urea Cycle? a) Ornithine b) Argininosuccinate c) Urea d) Glutamine Correct answer: Argininosuccinate Which enzyme converts Argininosuccinate to Arginine? a) Arginase b) Citrulline Synthetase c) Argininosuccinate Lyase d) Carbamylphosphate Synthetase Correct answer: Argininosuccinate Lyase What are the end products of Arginine conversion in the Urea Cycle? a) Lactate and Pyruvate b) Urea and Ornithine c) Citrulline and Glutamine d) Argininosuccinate and Ammonia Correct answer: Urea and Ornithine What is a primary diagnostic indicator of Hyperammonemia? a) Increased BUN levels b) Elevated ammonia levels c) Normalized glutamine levels d) Decreased citrulline levels Correct answer: Elevated ammonia levels What happens to Blood Urea Nitrogen levels in Hyperammonemia? a) They increase b) They remain stable c) They decrease d) They fluctuate wildly Correct answer: They decrease What is the significance of elevated blood glutamine in Hyperammonemia? a) It signifies dehydration b) It shows low protein intake c) It indicates ammonia overload d) It reflects high carbohydrate diet Correct answer: It indicates ammonia overload Which deficiency is characterized by elevated carbamylphosphate levels? a) Ornithine Transcarbamylase (OTC) Deficiency b) Arginase Deficiency c) Citrullinemia d) Carbamylphosphate Synthetase 1 Deficiency Correct answer: Ornithine Transcarbamylase (OTC) Deficiency What additional compound is elevated in OTC deficiency? a) Arginine b) Citrulline c) Orotic acid d) Urea Correct answer: Orotic acid What condition can result from OTC deficiency? a) Hyperammonemia b) Lactose intolerance c) Diabetes mellitus d) Iron deficiency anemia Correct answer: Hyperammonemia What is the diagnosis for OTC deficiency based on urine findings? a) High urine glucose b) Low nitrogen excretion c) Orotic acid urea d) Negative urine ketones Correct answer: Orotic acid urea What specific details are missing for CPS 1 deficiency? a) Treatment options b) Common risk factors c) Prevention methods d) Symptoms and diagnosis specifics Correct answer: Symptoms and diagnosis specifics How toxic is the ammonium ion compared to ammonia? a) Less toxic, with a toxicity level of 0.5 mg. b) More toxic with a level of 1 mg. c) Equally toxic as ammonia at 0.5 mg. d) Non-toxic, with no defined level. Correct answer: Less toxic, with a toxicity level of 0.5 mg. What is the physiological concentration of ammonium ion relative to ammonia? a) Equal concentration to ammonia. b) 10-fold lower concentration of ammonium ion. c) 100-fold higher concentration of ammonium ion. d) 50-fold higher concentration of ammonia. Correct answer: 100-fold higher concentration of ammonium ion. What is a critical implication of a complete block in the urea cycle? a) It causes mild symptoms only. b) It is incompatible with life. c) It enhances nitrogen metabolism. d) It allows for increased ammonia production. Correct answer: It is incompatible with life. What condition arises from defects in the urea cycle? a) Hyperammonemia. b) Hypoammonemia. c) Hypoglycemia. d) Protein deficiency. Correct answer: Hyperammonemia. What symptom is associated with hyperammonemia? a) Increased tolerance to protein ingestion. b) Intolerance to protein ingestion. c) Improved mental function. d) Increased stress response. Correct answer: Intolerance to protein ingestion. What kind of deficiencies may occur in hyperammonemia patients? a) Mental and CNS deficiencies. b) Muscle and bone deficiencies. c) Cardiovascular and respiratory issues. d) Vision and hearing impairments. Correct answer: Mental and CNS deficiencies. What is a common treatment approach for hyperammonemia? a) High carbohydrate diet. b) Increased protein intake. c) Low protein diet. d) No dietary changes. Correct answer: Low protein diet. Which treatment may help mitigate ammonia accumulation? a) Beta Hydroxybutyrate. b) Gamma Aminobutyric Acid. c) Delta Catenine. d) Alpha Keto Glutarate. Correct answer: Alpha Keto Glutarate. What is the primary benefit of urine's acidic nature? a) It increases ammonia levels in the body. b) It traps ammonia as the ammonium ion. c) It neutralizes bacterial infections. d) It promotes the excretion of glucose. Correct answer: It traps ammonia as the ammonium ion. How does ammonia's toxicity compare to the ammonium ion? a) Ammonium ion is more toxic than ammonia. b) Both have equal toxicity levels. c) Ammonia is significantly more toxic than ammonium ion. d) Ammonium toxicity is negligible compared to glucose. Correct answer: Ammonia is significantly more toxic than ammonium ion. What is the main function of glutaminase? a) Breaks down amino acids into glucose. b) Converts pyruvate into glucose. c) Removes nitrogen to generate glutamate and glutamine. d) Detoxifies peroxide in peroxisomes. Correct answer: Removes nitrogen to generate glutamate and glutamine. What is the significance of L and D amino acid oxidases? a) They convert glucose into fatty acids. b) They synthesize glutamate from nitrogen. c) They produce ammonia as a byproduct. d) They generate peroxide while breaking down D amino acids. Correct answer: They generate peroxide while breaking down D amino acids. What is the primary purpose of the glucose-alanine cycle? a) To conserve glucose backbones for energy. b) To detoxify nitrogen compounds. c) To convert ammonia to ammonium. d) To synthesize D amino acids. Correct answer: To conserve glucose backbones for energy. Where is catalase primarily found in the cell? a) In the mitochondria. b) In the endoplasmic reticulum. c) In the nucleus. d) In the peroxisomes. Correct answer: In the peroxisomes. At what ammonia level do toxicity issues arise? a) Levels greater than 5 micrograms per liter. b) Levels greater than 10 micrograms per liter. c) Levels greater than 50 micrograms per liter. d) Levels greater than 100 micrograms per liter. Correct answer: Levels greater than 10 micrograms per liter. What is the toxic level of the ammonium ion? a) Around half a milligram. b) Around 10 micrograms. c) Around 1 milligram. d) Around 5 milligrams. Correct answer: Around half a milligram. What effect does the higher concentration of ammonium ion have? a) It mitigates ammonia's toxicity. b) It increases glucose metabolism. c) It enhances nitrogen removal from the body. d) It promotes urea production. Correct answer: It mitigates ammonia's toxicity. Why is a complete block in any step of the urea cycle critical? a) It increases ammonia levels excessively. b) It reduces protein synthesis efficiency. c) It is incompatible with life. d) It decreases glucose production in the brain. Correct answer: It is incompatible with life.