1/5/2021 Study Stack - USMLE Biochem Table Review

USMLE Step 1 Biochemistry

Question Answer
What changes a cytosine into a uracil? a Deaminase
Which base nucleotides contain an extra amino
AdenineCytosine
group?
Which base nucleotide has an extra methyl group? Thymine(THYmine = meTHYl)
Purines: Adenine & Guanine (PURe As
What are the purines?Pyrimidines? Gold)Pyrimidines: Cytosine, Uracil & Thymine (CUT
the Py)
How does Methyltrexate work on DNA? prevents changing a uracil to a thymine
If a sample of DNA has 10% G, how much is the T %? 10% G + 10% C = 20%therefore 80%/2 = 40% T
Which DNA has a higher melting point?Why?De ne CG bonds They have a triple H-bondMelting point =
melting point. 50% double-stranded & 50% single-stranded DNA
What is the charge of Histones?What 2 AA are
PositiveArginine & Lysine
histones abundant in?
what causes chromatin to be tightly packaged?
Name of this type of chromatin? (active or
inactive)If it is not packed tightly, what is it sensitive H-1Heterochromatin - inactivenucleases
to?
Endonuclease activation and chromatin
fragmentation are characteristic of cell death by 10 nm ber(this is the chromosome without the H-1;
apoptosis. What nucleic cell structure would most ber b/t a nucleosome)
likely be degraded rst in an apoptotic cell?
number of origins the prokaryote and eukaryote
Pro - oneEu - many
can begin with regarding DNA replication?
What is the same structure in DNA and RNA
both require a DNA template
synthesis?
Something that helps attach nucleotides via a PDE
Polymerase(Polymer = glue)
bond to make a new nucleic acid
What is needed to begin DNA synthesis?RNA
DNA: RNA primerRNA: nothing
synthesis?
What has the ability to proofread DNA?How and in
DNA polymerase III3' -> 5' Exonuclease
what direction?
What recognizes the Origin of replication in a
Prokaryotic: DNA A proteinEukaryotic: nothing
prokaryotic and eukaryotic cell?
Unwinds DNA in Prokaryotic and eukaryotic cells?
Helicase(requires ATP)
What does it require?
What stabilizes unwound template strands of DNA? SSB(Single-stranded DNA-binding protein)
What synthesizes RNA primers? Primase
Responsible for synthesis of Leading strand of DNA
Pro: DNA polymerase IIIEu: DNA polymerase Delta
in the prokaryotic cell? Eukaryotic cell?
Responsible for synthesis of Lagging strand of DNA
Pro: DNA polymerase IIIEu: DNA polymerase Alpha
in the prokaryotic and eukaryotic cell?
What is responsible for the REMOVAL of RNA
primers in prokaryotic cells? In what Pro: DNA poly I 5' -> 3' exonuclease activity
direction/activity?
What is responsible for replacement of RNA primer
DNA poly I
w/ DNA?
Joins Okazaki fragments DNA ligase
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Removes positive supercoils ahead of advancing

replication forks? DNA topoisomerase II
Synthesis of telomers in prokaryotic and eukaryotic
Pro: not required (circular)Eu: Telomerase
cells?
What requires an RNA template to direct the RNA-dependent DNA polymerase(Reverse
synthesis of new DNA? Transcriptase)
DNA repair have two main enzymes that do all the
DNA polymeraseDNA ligase
REPAIR work...what are they?
What excises thymine dimers? Excision endonuclease
What phase of cell cycle does a mismatch base
Occurs: SFixed: G2
problem occur?What phase is it xed?
What is used to proofread human DNA? 3' -> 5' Exonuclease activity of DNA poly Delta
What do each of the (3) eukaryotic RNA RNA poly I: rRNARNA poly II: mRNA, hnRNARNA
polymerases make? poly III: tRNA, 5S rRNA
What DNA strand should you assume the boards Coding strand(strand you will build a template strand
mean if it is not labeled? from)
During RNA synthesis, the DNA template sequence
TAGC would be transcribed to produce which of the GCUA(always write in 5'->3' direction)
following sequences?
What initiates the promoter in the prokaryotic cell? intiate: Sigmaterminate: Rho + stem & loop (or
What may be required to terminate transcription? UUUUU + stem & loop)
What is the initiation codon on the CODING strand
ATG(corresponding to AUG RNA)
of a transcription unit?
What does the promoter consist of in a prokaryotic
(-35) sequence & (-10) TATAATstarting site: +1
cell?What is the "number" of the starting site?
What does the promoter consist of in a eukaryotic
(-70) CAAT + (-25 TATA box) Transcription Factors
cell? (2)What binds the promoter?
What is the portion just before the initiation codon Shine-Dalgarno sequence16S RNA of prokaryotic
of a prokaryotic cell called? What recognizes this? ribosome
What is the term referred to as the creation of a monocistronicEukaryotic (polycistronic is
single protein?What type of cell does this? prokaryotic)
3 posttranscriptional processing steps for 1. 5' Cap (7-MeG)2. 3' poly-A tail3. removing interons
eukaryotics w/ splicesome
where does transcription and translation occur in
transcription - nucleustranslation - cytoplasm
the eukaryotic cell?
Transition - purine for purineTransversion - purine for
de ne:TransitionTransversion
pyrmidine
Mutation type in DNA that creates a new codon Missense
Mutation type in DNA that creates a stop codon Nonsense
UGA (U Go Away)UAA (U Are Away)UAG (U Are
3 stop codons
Gone)
What type of genetic problem is caused by a
Frameshift mutation
deletion or addition of a single base?
blood problem that is a result of a large segment
alpha-thalassemia
deletion
blood problem that is the result of a splicing of the
donor or acceptor sites (beginning of beta-thalassemia
interons/exons)
What is responsible for accuracy of the amino acid
selection along with tRNA?what is needed to Aminoacyl-tRNA2 high-energy ATP bonds
activate this?
What does the UCG anti-codon code for? CGA (remember to read anti-codon backwards: 5'-
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>3')
What is the bond between two amino acids called?
peptide bond occurs in the ribosome
Where does this form?
What is the anti-codon for the start codon? CAU
What site in the rRNA does the tRNA bring the AA
to? What amount of energy is needed to translate a A-site (acceptor) 4 GTP
protein?
Primary - Amino Acids Secondary - folded AA into a-
helix or b-sheet Tertiary - 3-D the secondary
Describe the 4 levels of protein shape
structures Quarternary - multiple subunits (ex - Hb:
2a2b)
N-terminus (NH2) of newly translated protein is
Why is there "rough" ER? hydrophobic, so the rRNA will move to and attach to
the ER to complete translation within the ER
What does the golgi do to the new protein? adds sugars to the N-terminus
What AA does the golgi add N-oligosaccharides to?
N: Asparagine O: Serine and Threonine
O-oligosaccharides? (2)*
What does the golgi do if it wants to send the new Adds Mannose-6-Phosphate via phosphotransferase
protein to the lysosomes?
Dx: protein creation problem that accompanies the
signs of coarse facial features, gingival hyperplasia, Dx: I-cell disease Missing: Phosphotransferase (can't
joint immobility, growth/psychomotor retardation, send proteins to lysosomes)
cardioresp failure in rst decade. What is missing in
protein creation?
2 cells rich in RER Goblet cells of the GI Ab-secreting Plasma cells
What cell organelle is responsible for steroid Smooth ER also responsible for: detoxi cation of
synthesis? What else is it responsible for? drugs and poisons
Covalent modi cation to proteins by adding 2
negative charges to allow calcium to bind. What Gamma-carboxylation Clotting factors 2, 7, 9, 10
important function uses this method? What drug (Warfarin prevents gamma-carboxy)
prevents this?
Most prevalent AA in collagen? Two other common Glycine Proline & Lysine
AA in collagen?
Where does hydroxylation of preprocollagen occur? Proline & Lysine are hydroxylated in the ER Vitamin C
What is hydroxylated? What cofactor is needed for is required
it to occur?
What occurs to collagen after it is hydroxylated? In Glycosylated in Golgi Triple helix (Procollagen)
what part of the cell? What is formed here? Name?
Following glycosylation of collagen, what is the next
step and alteration of the structure? What is it now Procollagen is secreted from the cell. Then terminal
ends are cleaved. Then called: Tropocollagen
called?
What is needed to make the tropocollagen into
Lysyl Oxidase & Copper
brils and stabilizes this structure? (2)
(4)* Collagen synthesis de ciencies SOME: 1. Scurvy 2. Osteogenesis Imperfecta 3.
Menkes Dz 3. Ehlers-Danlos
Dx: Petechiae, ecchymoses, bleeding gums, poor Scurvy De ciency: hydroxylation of collagen
wound healing, poor bone development De ciency? de ciency secondary to lack of Vit-C
Dx: Skeletal abnormalities, multiple fractures, blue Osteogenesis Imperfecta
sclera
Dx: Hyperextensible, fragile skin, hypermobile
joints, vericose veins, arterial and intestinal Ehlers-Danlos De ciency: Lysine hydroxylase
ruptures De ciency? collagen de ciency secondary to lack of copper
To compare collagen counts of several tissues, what hydroxyproline or hydroxylysine (not Glycine--b/c it's
could be measured? prevalent in other tissues)
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Dx: 6 month infant has fractured rib; subdural Menkes disease Lysyl Oxidase in collagen
hematoma; thin, colorless, tangled hair; low serum metabolism, which requires copper
copper; developmental delay. What enzyme is
de cient?
What do pseudomonas and diphtheria toxins inhibit eEF-2: translocation factor
in eukaryotic translation?
What sequence is found at the 3' end of the tRNA? CCA then the Amino acid
What intermediate is formed by the splicing of the Lariat-shaped intermediate snRNA ("Snurp")
interons out of the mRNA transcripts? What facilitates
facilitates the splicing?
Glucose: Repressor-ON; CAP-OFF Lactose:
With the lac opeon, what is on/off if only glucose is Repressor-OFF; CAP-ON (Z, Y, A, made) Both:
present? Only Lactose? Both? When is Z, Y, A made? Repressor-OFF; CAP-OFF (glucose causes CAP off
and Lactose causes Repressor off)
What favors gene expresson--histone acetylases or histone acetylases - open hisones anything that
condenses or bulks chromatin does not favor gene
deacetylases? Why? expression
Where are enhancers located? may be upstream, downstream or within interon of
gene they control (due to looping)
When you see "zinc ngers", "leucine zippers", or Enhancers (steroid receptors are ngers, while cAMP
"helix-loop-helix", what are they talking about?
What are the ngers? response elements are zippers)
If you have multiple abnormalities with a single HOX or PAX gene
gene point mutation, where is the mutatuion?
Dx: childhood obesity and hyperphagia,
hypogonadotrophic hypogonadism, small hands and Prader-Willi syndrome Genetic Imprinting (father's
feet, mental retardation, hypotonia Type of genetic gene only)
problem?
Dx: mental retardation, continuous laughing Type of Angelman syndrome "Happy Puppet syndrome"
genetic problem? Genetic Imprinting (mother's gene only)
What does bacteria do to protect its DNA? How
does it destroy foreign DNA (bacteriophage)? it Methylates its DNA Restriction endonucleases
What do restriction endonucleases recognize in the palindromes
sequence?
Library made from nuclear DNA and is good for
seeing all sequences in the cell. Which library is Genomic Libraries cDNA Libraries
good for seeing proteins (exons) without introns?
Example of a key tissue for collagen types 1-4 Bone SCAB: I: bone, Skin II: Cartilage III: Arteries IV:
Basement membrane (4 to the oor)
What is a key feature to a Dominant genetic Dominant - every generation is affected (not in
problem in pedigree (vs. recessive)? recessive)
What is a key feature to Autosomal genetic problem Autosomal - Male-to-male inheritance (x-linked has
in pedigree (vs. X-linked)? no male-to-male)
Dx: Lateral displacement of the innercorner of the
eye; Pigment abnormalities; congenital deafness; Klein-Waardenburg Syndrome HOX gene
limb abnormalities What gene is the problem? abnormality
If cystic brosis patient were to be treated with
gene therapy, which type of cells should be targeted Epithelial cells
by the host cells?
FH-MAN Familial Hypercholesterolemia;
name 5 Autosomal Dominant diseases Huntingtons; Marfans; Acute Intermittent Porphyria;
NF-1
What is usually the common problem in the Structural protein damage
Autosomal Dominant diseases?

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name 4 common Autosomal Recessive diseases SCriPT Sickle cell; Cystic Fibrosis; PKU; Tay-Sachs
What type of genetic diseases affect energy Mitochondrial Diseases: Leber's optic neuropathy;
production? (Name 3) MELAS; MML
name 4 X-linked recessive common diseases Duchennes muscular dystrophy; Lesh-Nylan; G6PD;
Hemophilia A & B
Paternal relationships b/t man and infant can best
be determined by DNA ngerprinting. What about Tandem repeats
the DNA is analyzed?
2 amino acids that are the precursors for Phenylalanine Tyrosine
catecholamines
What NT does tryptophan form? What vitamin? Serotonin Niacin
3 branched-chained amino acids found in Maple I Love Vermont: Isoleucine; Leucine; Valine
Syrup Urine disease?
name the (6)* nonpolar, non-aromatic hydrophobic VIP GAL: Valine; Isoleucine; Proline Glycine; Alanine;
amino acids Leucine
Only amino acid with a phenol group? Tyrosine
name the 3 aromatic amino acids Phenylalanine Tyrosine Tryptophan
the amino acid that acts as a methyl donor methionine (SAM)
name 3 amino acid that are basic What is the pK of HLA: Histidine (6.5) Lysine (10) Arginine (13)
the R groups?
name the 2 amino acids that are acidic What is the
pK of the R groups? Glutamate (4) Aspartate (4)
What are the 2 pKs that every amino acid has? pk (COO-) = 2 pk (NH2) = 9
What is the net charge on the amino acid if the pH is
less then the pI? positive

What is the pI? (equation) average of the pKs: (2+9)/2 = 5.5 for normal AA
[average the 2 closest numbers for charged AA]
Main extracellular buffer bicarbonate
10 essential amino acids PVT TIM HALL: Phe-Val-Thr Trp-Ile-Met His-Arg-
Leu-Lys
What 2 essential amino acids are required during
periods of growth? Histidine Arginine
What is the sign of delta G in a spontaneous negative
reaction?
Affect on Km & Vmax: 1) Competitive Inhibitor 2) Competitive: Km= Increase; Vmax= no change Non-
Non-competative Inh competitive: Km= no change; Vmax= Decrease
what does the x and y axis measure on Lineweaver- x-axis: -(1/Km) y-axis: (1/Vmax)
burke plots?
How does af nity relate to Km? low Km = high Af nity
amino acid precursor to GABA Glutamic Acid
amino acid precursor to Heme Glycine
the amino acid that is the precursor for: Creatine
Urea Nitric Oxide Arginine
adds a phosphate to a substance Kinase
2 serine kinases cAMP cGMP
which receptor type has no g-protein and results in
smooth muscle relaxation? Second messenger? cGMP Protein kinase G
What phosphorylates in the insulin/glucagon world? Glucagon - phosphorylates (needs ATP) Insulin - de-
Which needs ATP? phosphorylates
removes a phosphate from a substance Phosphatase
What bug affects ADP-ribosylation at Gs stimulates Gs- Cholera (stimulates the stimulator)
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receptors? What bug affects it at Gi? What do they inhibits Gi- Pertussis (inhibits the inhibitor) Both
both cause in the cell? cause: Increase in cAMP
What two Vitamins can be used in dehydrogenase
reactions? Ribo avin (B2) Niacin (B3)
Vitamin that makes CoA? Pantothenic Acid (B5)
What (4)* things does the liver produce in a well-fed G-TAB: GLYCOGEN Triglyerides ATP Bile (from
state? cholesterol)
What is the rst step in a well-fed state for the
following tissues: liver, RBC, brain, muscle, fat? GLYCOLYSIS
2 actions of RBC in a well-fed and fasting state? 1) glycolysis (for ATP) 2) Lactate production
What tissues use insulin receptors: GLUT 1 and 3? RBC Brain
What tissues use receptor: GLUT 2? Liver
What tissues use receptor: GLUT 4? Muscle Adipose
Once there is enough energy in liver during well-fed Glucose & Acetyl-CoA Glucose - added together to
state, what 2 substances build-up? What is done be stored as glycogen Acetyl-CoA - added together to
with them? become fatty acids (then transported to adipose via
VLDL)
What does adipose do during well-fed states? takes in glucose and fatty acids to make ATP and fat
What (4)* substances enter the liver during a well- Goes to Liver And Grows: Glucose - food (blood)
fed state? Where is each from? Lactate - RBC Amino Acids - food (blood) Glycerol -
Chylomicrons (food)
What does the liver give to tissues during fasting
states? To what tissues? Glucose - RBC & Brain Ketone bodies - muscle

What does muscle get during the fasting state? (2) Ketone bodies - liver (once enough ATP is made and
From where? Aceytl-CoA builds-up) Fatty acids - Adipose (carried
on albumin)
What does the muscle provide to the liver during Amino Acids 1. to make Pyruvate (then glucose) 2. for
fasting states? For what? (2) Urea cycle
2 sources (& preliminary substances) to make RBC - lactate muscle - Alanine
pyruvate b/t meals for the liver to make glucose
What 2 ways can the GLUT-4 receptor move to the
1) Increased Insulin 2) Exercise
surface of muscle?
What are the 2 anaerobic steps of substrate level 1,3BPG --> 3PG (via Phosphoglycerate kinase) PEP --
phosphorylation in glycolysis? > Pyruvate (via Pyruvate kinase)
What are two essential items needed to make ATP 1) Oxygen 2) Mitochondria (for ETC)
from NADH?
First and third step: Glucose --> G6P (via
What 2 steps of glycolysis use ATP? Hexokinase/Glucokinase) F6P --> F-1,6-BP (via PFK-
1)
What is the rate-limiting step of glycolysis? Net PFK-1 2 ATP (net)
ATP?
How does the RBC replenish NADH? With what Pyruvate --> Lactate (Enzyme: Lactate DH) changes
essential enzyme? If enzyme was not there, what NAD+ --> NADH for glycolysis (lactate goes to liver)
would occur? If Lactate DH not there, RBC would die
What enzyme of glycolysis is only in the liver and is Glucokinase Low af nity = High Km = high Vmax
induced by insulin? Level of af nity of this enzyme?
Insulin (dephos) stimulates PFK-2 for: F6P --> F-2,6-
How is PFK-1 controlled? Which form is active BP to make PFK-1 Glucagon (phosphorylates)
(dephosphorylated or phosphorylated)?
inhibits PFK-2
What (3)* metabolic events occur in the Fatty acid oxidation Acetyl-CoA production TCA
mitochondria? cycle
What (5)* metabolic events occur in the cytoplasm? Glucose Found Here Protects Steroids: Glycolysis
Fatty acid synthesis HMP shunt Protein synthesis
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(RER) Steroid synthesis

What (3)* metabolic events occur in both the
Heme synthesis Urea cycle Gluconeogenesis
mitochondria and the cytoplasm?
What 2 shuttles take NADH from the cytoplasm to
the mitochondria? How many ATP does each yield? Malate/OAA Shuttle - 3ATP G3P Shuttle - 2ATP
Which yields a FADH2 instead of the NADH in the (creates FADH2)
mito?
If a patient has cataracts early in life, what is the
underlying metabolic problem? What toxic Galactose metabolism Toxic: Galacititol
substance accumulation causes this?
Dx: young patient with hepatosplenomegaly, Galactosemia: Galactose-1-P uridyltransferase = at
cataracts, mental retardation. Which enzyme
birth; Galactokinase = early childhood
presents sx at birth? Which in early childhood?
Dx: lethargy, vomiting, liver damage,
hyperbilirubinemia, hypoglycemia, jaundice, renal
proximal tubule problems. What enzyme is Fructose Intolerance Enz: Aldolase B
de cient?
What are the (5)* cofactors used for Pyruvate TLC For Nipples: Thiamine (B1) Lipoic Acid
Dehydrogenase? Coenzyme A (B5) FADH2 (B2) NADH (B3)
What does Pyruvate DH change pyruvate into? Acetyl CoA
Overall net reaction of the TCA cycle? What makes Acetyl CoA --> 2 CO2 3NADH + FADH2 + GTP = 12
the ATP in this reaction? ATP (2x everything per one glucose)
Which enzyme in the TCA cycle is in the inner
mitochondrial membrane versus the matrix of the Succinate Dehydrogenase
mitochondria?
What enzyme has the same 5 cofactors as Pyruvate Alpha-Ketogluterate DH
DH?
Can I Keep Selling Sex For Money Of cer? Citrate--
In order, what are the 8 steps in the TCA cycle? >Isocitrate--> (alpha)Ketogluterate--> Succinyl CoA--
>Succinate--> Fumarate-->Malate-->OAA
What does a Pyruvate DH de ciency lead to? What Lactic Acidosis (from backup of substrates) Seen in
Alcoholics (thiamine de ciency) Tx: Ketogenic acids
can it be due to? How is it treated?
(Lysine & Leucine)
What part of the TCA cycle is also part of the ETC? Succinate Dehydrogenase (Complex II) Provides:
What does it provide to the ETC? FADH2
What part of the TCA cycle deals with Fatty Acid Citrate
synthesis?
What part of the TCA cycle deals with Heme
synthesis? Succinyl CoA
What part of the TCA cycle deals with the Urea
Fumarate
cycle?
What parts of the TCA cycle deals with
OAA & Malate
Gluconeogenesis?
What is the rate limiting step of the TCA cycle? Isocitrate DH depends on NADH levels
What does it depend on?
KIM SUCkS: Ketoglutarate DH - NADH Isoglutarate
What enzymes in the TCA produce the energy? (5)* DH - NADH Malate DH - NADH Succinyl CoA - GTP
Succinate DH - FADH2
What does Complex I use in ETC? What drug class NADH Barbiturates
inhibits Complex I?
What 3 reactions add FADH2 to Coenzyme Q? TCA (Succinate DH) [Complex II] Glycerol-P shuttle
Which is considered Complex II? Beta-oxidation (Fatty Acyl CoA DH)
Which Complex in the ETC uses Oxygen? Another Complex IV (Cyto a/a3) copper Cyanide & CO
name for thtis complex? What else is needed for
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this Complex? What 2 compounds inhibit this

Complex?
Where is the ATP made in the ETC? What inhibits ATP Synthase Inhibitor: Oligomycin
this?
Aspirin Brings H+ across the proton gradient, which
What is a common Uncoupler? How does it work? inhibits the creation of ATP and increases Oxygen
consumption
What is the rate limiting step in Glycogen creation? UDP-Glucose --> Glycogen (via Glycogen Synthase)
In which type of muscle ber is glucose converted to Lactate: White (fast) bers completely oxidized:
to Lactate? In which type is it completely oxidized? Red (slow) bers
What converts Glycogen back into Glucose 1-P? Glycogen Phosphorylase Stimulated by: Liver:
Glucagon and Epinephrine Muscle: AMP and
What stimulates it in the liver and muscle? (2 each)
Epinepherine
What are the (4)* main Glycogen storage diseases? Very Poor Carbohydrate Metabolism: Von Gierke
(in order I, II, III, V) Pompe Cori McArdles
Dx: Glycogen storage disease that causes severe Von Gierke's (Glucose-6-Phosphatase) "LU Von
hypoglycemia, hepatomegaly, hyperlipidemia &
Geirke is 6" [LU = hyper Lipidemmia and Uriceia]
hyperuricemia What is the de cient enzyme?
Dx: Glycogen-like material in inclusion bodies,
cardiomegaly, muscle weakness and death by age 2 Pompe's (Lysosomal-alpha-1,4-glucosidase)
What is the de cient enzyme?
Dx: Glycogen storage disease that is similar, but
Cori's (Alpha-1,6-Glucosidase) [Cori is A-16 yo-Girl]
milder then Type I. What is the de cient enzyme?
Dx: Increased glycogen in muscle, painful cramps,
myoglobinuria w/ exercise What is the de cient McArdle's (Muscle Glycogen Phosphorylase)
enzyme?
What are the 3 irreversible steps in Glycolysis? Glucokinase PFK-1 Pyruvate Kinase
What are the (3)* ways Gluconeogenesis Pathway Produces Fresh Glucose: Pyruvate
circumvents the irreversible glycolysis steps (in Carboxylase/PEPCK F-1,6-Bisphosphatase Glucose-
order)? 6-phosphatase
What are the (3)* cofators for Carboxylase ABC enzymes: ATP Biotin CO2
reactions?
What is the rate-limiting enzyme in
Gluconeogenesis? PEPCK
What enzyme converts Pyruvate to OAA? How
does this OAA get to the cytoplasm to create Pyruvate Carboxylase Malate/OAA shuttle
Glucose?
What is an easy test to see if patient has a glycogen inject patient with glycerol; if patient does not
storage disease? increase blood glucose, there is a G6P de ciency
Cycle that Transfers excess reducing agents from
RBC and muscle to the liver, allowing the muscle to Cori Cycle RBC and Muscle give: Lactate
function anaerobically What do the muscle and
RBC distribute to the cycle?
What enzyme changes lactate to and from
Lactate DH
pyruvate?
What is the function of the HMP shunt? What are to regenerate NADPH and Ribose 5-P Enzymes:
the 2 important enzymes in this reaction? G6PDH Transketolase (TPP)
Liver: Biosynthesis (FA, Cholesterol, DNA) RBC:
What are the 3 main roles of NADPH? Protect against ROS Neutrophil: NADPH oxidase (kill
bugs)
What are the 2 essential Fatty acids? What is their Linoleic = C18:2(9,12) Linolenic = C18:3(9,12,15)
nomenclature?
What cells have telemorase activity? (2) Embryonic (germ) cells Cancer cells
What strand is identical to the mRNA (except T for Identical: Coding Strand Complementary: Template
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U)? What strand is Complementary and antiparallel Strand

to the mRNA (except T for U)?
What drug inhibits all transcription in prokaryotes
Actinomycin D
and eukaryotes?
What is 3 bases and antiparallel to mRNA w/ U Anti-codons attached to tRNA
instead of T? where is this attached?
(2) steps of Collagen formation that occurs in the 1. Removal of the "Pre" from Prepro-alpha to make
RER? What Dz can occur from a de ciency in these Pro-alpha 2. Hydroxylation of the Pro-alpha with
steps? Vitamin C Dz: Scurvy (Vit-C de ciency)
(2) steps of Collagen formation that occurs in the 1. Glycosylation 2. Triple Helix formation to make
Golgi? What Dz can occur from a de ciency in these
steps? Procollagen Dz: Osteogenesis Imperfecta
1. cleavage of peptide ends to make Tropocollagen 2.
(3) steps of Collagen formation that occurs in the Tropocollagen into brils w/ Lysyl Oxidase and
ECM? What (2) Dz can occur from a de ciency in copper 3. Fibrils to Collagen Fibers Dz: Ehlers-Danlos
these steps? (Lysine hydroxylase de ciency) Menke's Dz (Copper
digestion insuf ciency)
Drug that is against Pertussis by inhibiting the
translocation of peptidyl-tRNA on 50s ribosome Erythromycin
What effect does Exotoxin A of Pseudomonas have
inhibits translocation factor: eEF-2
on the human cells?
Plasmid: circular DNA in bacteria Vector: carrier for
De ne: 1. Plasmid 2. Vector 3. Phage human DNA to insert into a plasmid Phage: Larger
vector
What type of Genetics: NO male to male; no male to
Mitochondrial inheritance
female; if mother has it, all kids have it
DNA (negative charge) moves to the positive Larger
With Southern blot, how does the DNA align? (2)
fragments at top and smaller at bottom
What does it measure? 1.Southern blot 2. Northern
blot 3. Western blot Which is good to answer Southern = DNA (restriction fragments) Northern =
questions about gene expression? About the RNA (gene expression) Western = Proteins
amount of antigens or antibodies? To determine (Antibodies/Antigens)
speci c restriction fragments?
Gs = Beta receptors (stimulates Adenyl cyclase to inc
cAMP) Gi = Alpha-2 receptors (Inhibits Adenyl
Type of receptors: 1. Gs 2. Gi 3. Gq What does each cyclase to dec cAMP) Gq = Alpha-1 receptors
do?
(Stimulates Phospholipase C in PIP2 receptor
system)
Which receptor is associated w/ Protein Kinase C? IP3 (Gq)
Which receptor is assoc w/ Protein Kinase A? cAMP (Gs and Gi)
What is the G-receptor for Vasopressin? Glucagon? Gq - IP3 system Gs/Gi - cAMP system
MCC of de ciency in: Thiamine Alcoholism
MCC of de ciency in: Folic Acid (2) Alcoholism Pregnancy
MCC of de ciency in: Cyanocobalamin (B-12) Pernicious Anemia
MCC of de ciency in: Pyridoxine Isoniazid therapy
What NT is always released w/i the eyes (in the
dark) causing constant depolarization? What
Glutamic Acid cGMP-PDE Na+ gated channels close
channels respond to light causing the cell to
hyperpolarize?
What vitamin is used to introduce Calcium to
binding sites of several calcium-dependent Vitamin K Gamma-carboxylation of Glutamate
proteins? With which mechanism? What drug Warfarin inhibits it
inhibits this?
Bleeding time difference and PT difference b/t a Vit C: Increased bleeding time normal PT Vit K:
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de ciency in: Vit-C and Vit-K normal bleeding time Increased PT

If tissue is hypoxic, what enzymes will be increased Any Glycolysis enzyme (not Lactate DH)
in the blood?
MC genetic de ciency that causes hemolytic
anemia Pyruvate Kinase De ciency
What amino acid is assoc w/ the Malate-OAA
Aspartate
shuttle?
What enzyme in glycolysis is activated after a big
PFK-2 Activated by Insulin
meal? What activates it?
What thiamine-dependent enzyme is essential for Pyruvate DH
glucose oxidation in the brain?
After an overnight fast, what enxymes of what Glycolysis enzymes (b/c liver is producing glucose,
metabolic process would be insigni cant? not storing it)
What enzymes in the TCA cycle produce items but Succinates: Succinyl CoA Synthase = GTP Succinate
not NADH? (2) DH = FADH2
Which is the only enzyme in the TCA that deals w/
Succinyl CoA Synthase
substrate level phosphorylation?
Which direction do H+ ow in the ETC? In which Mitochondrial matrix -> cytoplasm: Complexes I, III
complexes? In which complex is the ow the
and IV Opposite direction: ATP synthase O2 -> H20:
opposite direction? Which side does O2 -> H20? On mitochondrial matrix on Complex IV
which complex?
What does Nitroprusside break down into? What
complex in ETC does it affect? Cyanide Complex IV
What glycogen storage Dz has debranching
Cori's Dz
enzymes?
If FA beta-oxidation is occurring in the liver, what
Carboxylates to OAA for entry into Gluconeogenesis
does pyruvate do?
What do G6PDH de cient patients have resistence Malaria
to?
What do the bilirubin levels in the blood and urine
look like w/ hemolytic jaundice (from G6PDH Direct = normal Indirect = increased Urinary = absent
de ciency)?
What type of bonds are there in alpha-helix and Peptide bonds that participate in H+ bonding
beta-sheet proteins?
What property of water most contributes to its
ability to dissolve compounds? Hydrogen bonds
What tissue has the highest concentration of
Keratin
Cystine?
What gives strength to the IgG structure? What can
Disul de bonds Urea (and reducing agents)
break these bonds?
What is constant (the same) in each class of Constant regions of the heavy chains
immunoglobulins?
How many antigen binding sites does each
immunoglobulin have per molecule? 2
Which FA is cardio-protective? Linolenic (omega-3)
When is a FA considered "saturated"? when it has NO double bonds
Name and give the nomenclature for the FA that is
the precursor to Prostaglandins, thromboxanes and Arachidonic Acid: C20:4(5,8,11,14)
Leukotrienes
1. Double bonds occur every 3 carbons 2. "L's" start
What is a good way to remember the placement of
w/ 9 3. Arachidonic C20:4 - take 20/4 = 5. This starts
the double bonds for unsaturated FA? (3) at 5
Accumulation of what in the liver triggers it to make Acetyl CoA Need Energy (ATP)
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fat? What is needed?

In the mitochondria, there are (2) pathways to make Fed (insulin): Pyruvate -> PDH -> Acetyl CoA ->
fat depending on the fed or fasting state. What is Citrate Fasting (glucagon): Pyruvate -> P Carboxylase
the path for each to get to Citrate? -> OAA -> Citrate
What from the mitochondria leaves the TCA cycle
to enter the cytoplasm for fat synthesis? What does Citrate Aceytl CoA
it then turn into?
What is the essential enzyme to transform Acetyl
CoA to Malonyl CoA? What else is needed? How Acetyl CoA Carboxylase ATP/Biotin/CO2 8 Acetyl
many Acetyl CoA are needed to make one CoA are needed for 1 Palmitate (7 cycles)
Palmitate?
What enzyme and substance is needed to convert
Malonyl CoA to Palmitate (16:0)? (2) FA Synthase (2) NADPH
How many molecules of NADPH are needed for one
14 NADPH (2 x 7 cycles)
Palmitate?
To transport FA from liver, what do you need to do
Convert it to a TG Need: Glycerol-3-P
to the molecule? What is needed for this?
(2) enzymes that are induced/activated by insulin in PDH Acetyl CoA Carboxylase
FA synthesis
What is needed for every Carboxylase enzyme? Biotin
1. Glucose enters liver: Glucose -> DHAP + Glycerol-
3-P DH -> Glycerol-3-P + 3 FA CoA -> TG 2. Glycerol
(2) ways to make TG in the liver
enters liver: Glycerol + Glycerol Kinase -> Glycerol-3-
P + 3 FA CoA -> TG
What in Adipose allows for the removal of FA from
TG carried by chylomicrons and VLDL? With what Lipoprotein Lipase Key: ApoC-II
"key"?
What is the only Apoprotein left on LDL? What is its ApoB-100 used as a key to LDL receptors in cell
membranes to endocytose the LDL for cholesterol
use?
usage
What are the (2) Apoproteins on HDL? Use of each? ApoE - Key to liver ApoA-1 - Key to stimulate LCAT
What does the LCAT receptor of peripheral tissues Adds a FA from the periphery to HDL for it to take
do? back to the liver
What are the main ingredients of the plaque on the "Fatty Streak" formation: Cholesterol Foam cells
vessel walls? (3) What is this called? (sick macros) Smooth muscle (migrated)
What membrane transport shuttle is used in Beta- Carnitine shuttle
oxidation of FA?
(2) main enzymes in B-oxidation of FA? Which is the Carnitine Acyl Transferase (rate-limiting across
rate limiting step? shuttle) Fatty Acyl CoA DH
What is the end product of b-oxidation? Acetyl CoA
When is the only time FA can go back into glucose? When it is a FA w/ an odd number Makes: Succinyl
What does it make in this case? CoA
What (2) enzymes are used in the breakdown of Propionyl CoA Carboxlase (biotin) Methylmalonyl
odd-chained FA? What is needed with each step? CoA Mutase (Vit B-12)
What is the difference b/t a TG and a glycerophospholipid has Inositol or choline attached
glycerophospholipid?
What are the (2) main ingredients in Sphingolipids?
Precursor to all sphingolipids? Serine (not glycerol) + FA Precursor: Sphingosine
Sphingolipids extra ingredients for: 1. Sphingosine 1. Sphingo = CHOLINE 2. Cerebro = SUGAR 3.
2. Cerebrosides 3. Gangliosides Ganglio = SIALIC ACID and complex sugars
De cient Lysosomal enzyme: Gaucher's Dz Glucocerebrosidase
De cient Lysosomal enzyme: Niemann-Pick Sphingomyelinase
What is the actual enzyme that causes the Aldose Reductase
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increased amount of Galactose to be converted into

Galactitol to cause Cataracts?
What are the enzymes for the (2) sources of Both break down Glutamate: Glutaminase in the GI
ammonia that enter the Urea cycle in the liver? Glutamate DH in liver
What vitamin is essential for aminotransferase Vitamin B-6
reactions?
If blood glutamate is increased in the blood, what is
De ciency in Urea cycle
the possible problem?
Careless Crappers AlSo ARe Frivolous About
Urination Outside: Carbamoyl Phosphate -> Citruline
What are the steps in the Urea cycle? (8)*
+ Aspartate -> Argininosuccinate - Fumarate ->
Arginine - UREA -> Ornithine
Which step in the Urea cycle is inside the
Carbamoyl Phosphate
mitochondria?
What is the enzyme de ciency with the following
Sx? blood glutamine increased, BUN decreased, Ornithine Transcarbamoylase (OTC)
cerebral edema, lethargy, convulsions, Uracil and
Orotic acid increase in blood and urine
What reactions and AA enter at the Succinyl CoA VOMIT SUCks: Valine; Odd-chain FA; Methionine;
part of the TCA? (5)* Isoleucine; Threonine
(2) enzymes in the body that need Vit B-12 Methylmalonic CoA Mutase Homocysteine Methyl
Transferase
What are the (2) Ketogenic AA? Where do they
Leucine Lysine enter at Acetyl CoA
enter the TCA cycle?
What (2) AA enter the TCA cycle at Fumarate? Phenylalanine Tyrosine
If you see zinc in heme, what enzyme is inhibited? Ferrochelatase
GAP UP Here: Glycine + Succinyl CoA ->
Steps in Heme Synthesis (6)* Aminolevulinic Acid (ALA) -> Porphobilinogen ->
Uroporphyrinogen-III -> Protoporphyrin -> Heme
What enzyme is de cient in Acute Intermittent
Uroporphyrinogen Synthase
Porphyria?
Dx: Painful abdomen; Pink urine (Port-wine urine); 4 P = Porphyria
Polyneuropathy; Psychological disturbances
Porphyria that also causes blistering of the skin
Porphyria Cutanea Tarda
from photosensitivity
Dx: Patient is given a barbituate and begins
projectile vomiting, confusion, abdominal pain, Acute Intermittent Porphyria
paranoia.
HCG: Hemolysis; Crigler-Najjar syndrome; Gilbert's
(3)* causes of Increased Indirect Bilirubin
syndrome
(2) conditions that increase Direct Bilirubin Hepatic damage Bile duct obstruction
What are the (2) required AA for Pyrimidine
synthesis? Glutamatine Aspartic Acid
Thymidine (dTMP) Drugs that block DHF reductase:
Blocking THF creation would lead to not being able
METHotrexate (cancer); TriMETHoprim (PCP);
to make what? What (3) drugs do this? What is the
PyriMETHamine (toxoplasmosis) Side effect: Bone
side effect of all of these drugs?
marrow Suppression
What are the (3)* important enzymes in the Right Here The Funky Drugs Mingle: Ribonucleotide
conversion of UMP to dTMP (in order)? Which Anti- Reductase (Hydroxyurea) Thymidylate synthase (5-
cancer med targets each? FU) DHF reductase (Methotrexate)
What is Orotic Acid involved in? Pyrimidine synthesis
What is the additional AA that is used to make
purines? Glycine

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What enzyme in Purine synthesis is the rate- PRPP Amidotransferase Drugs ("Purin"):
limiting step? What (2) drugs inhibit this step? AlloPURINol (Gout); 6-MercaptoPURINe (cancer)
What intermediate in purine synthesis is different
from guanine and adenine by one amino group and Hypoxanthine
is also an intermediate in the breakdown of purines?
Lack of the salvage pathway of purines leads to
LNS = Lacks Nucleotide Salvage: Lesch-Nyhan
what syndrome? What is the missing enzyme? What
syndrome HGPRTase Sign: Self-mutilation
is an unusual sign of this syndrome?
Adenosine Deaminase de ciency causes a lack of
what product? Inosine
Dx: 48-yo man w/ recessive condition is at high risk
for deep vein thrombosis and has had replacement Homocysteinuria Enzyme: Cystathionine Synthase
of ectopic lenses; no evidence of anemia. Enzyme AA: Methionine
that is de cient? What AA would be in excess?
Dx: Man has dark pigment of cartilage and arthritis, Alkaptouria Enzyme: Homogentisate Oxidase [AL
and dark urine What enzyme is de cient? KAPT a HOMe]
How do you treat Cystinuria? Alkalinize the urine w: Acetazolamide
Precursor to Ketone body formation HMG-CoA
Try HUNTING for MY FRIED X (eggs): Huntington's;
(4)* genetic Dz w/ Trinucleotide repeats
Myotonic Dystrophy; Friedreich's Ataxia; Fragile X

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