Biochemistry Section-USMLE Step 1 Questions and Answers 100% Correct

"Initiation" of protein tranlsation is activated by ATP hydrolysis. T/F?False; GTP hydrolysis after addition of an aa, where does the aminoacyl tRNA now bind to?30S ribosomal RNA (small one) after citrulline is produced and in the cytoplasm what happens next in the urea cycle?citrulline is combined with aspartate to make arginosuccinate which is then split into fumarate (which leaves to enter TCA) and arginine. Arginine is then converted to Ornithine (via arginase) giving off Urea which then goes to the kidney and ornithine reenters the urea cycle (combined with carbomyl phosphate to make citrulline) after day 3 of starvation, what is the main source of energy?adipose tissue for brain and heart (ketone bodies) and then go to vital protein degradation (organ failure) after glucose 6 P is converted to glucose 1 P , what is the next step in glycogenesis? then what?conversion to UDP glucose via UDP glucose pyrophosphorylase; glycogen synthase (rate limiting step ) after how long of starvation do glycogen reserves deplete? after this occurs, how are blood glucose levels maintained?1 day; adipose release of FFA, hepatic gluconeogenesis from peripheral tissue lactate and alanine and from adipose tissue glycerol and propionyl coA After N5N10 methylene THF donates a methyl for conversion of dUMP to dTMP what is it converted to?DHF after the PCR reaction, how do you actually visualize the DNA?do agarose gel eletrophoresis to separate the different sizes of the PCR products (sizes id the the fragment) are histones in heterochromatin or euchromatin more methylated? which had more acetylated histones?heterochromatin; euchromatin at what point is the amino acid correspondence to the mRNA code finalized?in the charging reaction! for this reason aminoacyl tRNA synthetase double checks by what products are gluconeogenesis and glycolysis linked so that they are not both occurirng at the same time?ATP is an allosteric inhibitor on both phosphofructokinase and pyruvate kinase and pyruvate hydrogenase; and fructose 2,6 BP which is an allosteric enhancer on phosphofructokinase is an allosteric downregulator on fructose 1,6 bisphophatase can a disorder be congential but not hereditary?yes! congenital simply means "born with"- hereditary is familial deamination of what pyrimidine makes what?cytosine to u