Study guides, Class notes & Summaries

UNE Biochemistry Final, Final, Final Exam Review UNE medical biochemistry already graded A A comatose infant is brought to the ER. In the course of the examination, plasma ammonia was found to be elevated 20-fold over normal values. Urine orotic acid and uracil were both greater than normal. A defect of which of the following enzymes is the most likely diagnosis? Ornithine transcarbamoylase Your patient presents with a deficiency of the enzyme that catalyzes synthesis of N-acetylglutamate (NAG...

Somatostatin reduces the secretion of both glucagon and insulin through which of the following mechanisms? a. Somatostatin activates an activator G-protein b. Somatostatin activates MAPK cascade c. Somatostatin activates an inhibitory G-protein d. Somatostatin uses Ca+2 as a downstream signal c. Somatostatin activates an inhibitory G-protein Insulin mediated glucose uptake by muscle and adipose tissue is a result of which of the following mechanisms? a. Translocation of GLUT 4 recep...

Control of Fatty Acid Synthesis vs. Oxidation When Insulin is HIGH --> fatty acid synthesis occurs When Glucagon is HIGH --> lipolysis, fatty acid B-oxidation, ketogenesis occur **These never happen at the same time! Lipolysis Process of releasing free fatty acids from triacylglycerols stored in the adipose IN THE FASTED STATE Steps of lipolysis 1) Hormone Sensitive Lipase: activated by glucagon and epinephrine TAGs are hydrolyzed into FFAs and glycerol (inhibited by insulin) ...

1. _______________ is commonly used as an oxidizing agent in catabolic pathways while _______________ is commonly used as a reducing agent in anabolic pathways. a. NAD+/FAD ; NADH 1. A 2-year-old boy is recently diagnosed with red-green color blindness which is an X-linked recessive disorder. Which of the following represents the genotype of this individual? a. X'Y' (X' recessive X allele and Y chromosome) 1. A 3-year-old boy who presented with generalized hypotonia, severe psychomotor ...

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The glucose-alanine cycle is a method of transferring ammonia from the skeletal muscle to the liver. In this process the non-toxic carrier of ammonia is which of the following compounds? Alanine Which of the following enzymes is correctly paired with its activator? N-acetylglutamate synthatase; arginine The urea cycle takes place in which of the following subcellular locations? the cytosol and the mitochondria Which of the following enzymes is regulated by N-acetylglutamate (NAGs)? CPS ...

The ribonucleotide reductase is important for converting ribose bases to deoxy form. This conversion is coupled with the oxidation of what compound Thioredoxin Under fasting conditions, elevated glucagon will activate what enzyme Hormone-sensitive Ligase Short-chain fatty acids and medium-chain fatty acids enter mitochondria by Diffusion In liver, what key inhibitory events ensures that newly synthesized palmitoyl-CoA is not immediately oxidized? carnitine palmitoyl transferase-1 (CPT1)...

Hemoglobin binds oxygen with a greater affinity in the: R state Hemoglobin bound to heme is termed a holoprotein. The heme or porphoryin ring is required for oxygen binding and it is termed a: prosthetic group Alpha helices and beta sheets are primarily stabilized by: H bonding Ligases are a class of enzymes characterized by their ability to: synthesize bonds between carbon atoms and an additional atom that is involved in the cleavage of a high energy bond. An enzyme inhibitor that i...

What enzyme is used by the gluconeogenic pathway but NOT in the glycolytic pathway? Phosphoenolpyruvate Carboxykinase PEPCK Newborn screening results show a biotinidase deficiency in a 2 day old infant. The deficiency impairs the infant's ability to reuse and recycle biotin. Due to the enzymatic deficiency, the activity of what enzyme is likely impaired? Pyruvate carboxylase If unregulated, which of the following pairs of enzymes would represent a futile cycle? Fructose 1,6 -bisphosphate ...

Which of the following best describes a protein domain? A section of a protein structure sufficient to perform a particular chemical or physical task If a mutation is made within the active site of an enzyme resulting in an increase in Km, which of the following will be true with respect to the enzyme kinetics? the enzyme will require a higher substrate concentration to reach 1/2 Vmax The following represents a series of reactions. As levels of B increase, this will decrease the conversion...

Which of the following lipoproteins is responsible for carrying cholesterol from peripheral tissues (i.e skeletal muscle) back to the liver? HDL What is the primary role of LCAT (Lecithin-cholesterol acyltransferase)? To esterify cholesterol transported by HDL Which enzyme is responsible for transferring triacylglycerol from VLDL to HDL in exchange for cholesterol? LCAT (Lecithin-Cholesterol Acyltransferase) Which of the following lipoproteins is responsible for the transport of dietary...