Free Biochemistry Practice

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Biochemistry

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Beta-oxidation products

Fatty acid oxidation Practice Question

Fatty acid oxidation: Beta-oxidation products

Trace how a pre-existing cis double bond bypasses one acyl-CoA dehydrogenase step during beta-oxidationIncluded in free practice

Charge and pI

Amino acid chemistry Practice Question

Amino acid chemistry: Charge and pI

Connect addition of negatively charged phosphate groups to isoelectric point while separating charge effects from molecular-mass separationIncluded in free practice

Codon logic

Translation Practice Question

Translation: Codon logic

Use reporter size, unchanged mRNA abundance, and suppressor-tRNA rescue to distinguish nonsense mutation from missense, frameshift, and initiation defectsIncluded in free practice

Competitive inhibition

Enzyme inhibition Practice Question

Enzyme inhibition: Competitive inhibition

Use unchanged $V_{\max}$ and the competitive-inhibition relationship to calculate inhibitor affinityIncluded in free practice

Cooperativity

Allosteric regulation Practice Question

Allosteric regulation: Cooperativity

Use Hill coefficients and preserved catalytic capacity to distinguish intersubunit communication from active-site failureIncluded in free practice

Cycle control

TCA cycle Practice Question

TCA cycle: Cycle control

Connect allosteric control of IDH3 to substrate accumulation and attenuated oxidative flux during increased energy demandIncluded in free practice

Denaturation forces

Protein structure Practice Question

Protein structure: Denaturation forces

Interpret refolding yields after changing the order of denaturant removal and thiol oxidationIncluded in free practice

Directionality

DNA replication Practice Question

DNA replication: Directionality

Track the location of the activating triphosphate before and after excision of a misincorporated nucleotideIncluded in free practice

ELISA versus Western blot

Immunoassays Practice Question

Immunoassays: ELISA versus Western blot

Interpret discordant ELISA and Western-blot results when a degradation fragment retains the recognized epitopesIncluded in free practice

Initial velocity

Enzyme assays Practice Question

Enzyme assays: Initial velocity

Use product-spike and product-removal controls to identify product-dependent distortion of late reaction ratesIncluded in free practice

Ion exchange logic

Chromatography Practice Question

Chromatography: Ion exchange logic

Use pH relative to pI and resin charge to remove acidic impurities before capturing a basic target proteinIncluded in free practice

Irreversible steps

Glycolysis Practice Question

Glycolysis: Irreversible steps

Predict which gluconeogenic substrates remain usable when the phosphofructokinase-1 bypass is blockedIncluded in free practice

Km interpretation

Enzyme kinetics Practice Question

Enzyme kinetics: Km interpretation

Infer $K_m$ and $V_{\max}$ from matched velocity data and distinguish enzyme saturation from increased substrate affinityIncluded in free practice

PDH regulation

Pyruvate metabolism Practice Question

Pyruvate metabolism: PDH regulation

Interpret incomplete flux rescue after PDH dephosphorylation in the continued presence of NADH and acetyl-CoAIncluded in free practice

PFK-1 logic

Glycolysis regulation Practice Question

Glycolysis regulation: PFK-1 logic

Interpret kinetic behavior of a regulatory-site mutant under low and high ATP concentrationsIncluded in free practice

Primer orientation

PCR Practice Question

PCR: Primer orientation

Identify the forward primer and calculate the reverse complement needed for inward-facing 3-prime extensionIncluded in free practice

Promoter logic

Transcription Practice Question

Transcription: Promoter logic

Integrate RNA-polymerase occupancy, nascent-transcript abundance, and mRNA-decay measurementsIncluded in free practice

Protein separation

SDS-PAGE Practice Question

SDS-PAGE: Protein separation

Integrate size-exclusion chromatography with nonreducing and reducing SDS-PAGE patternsIncluded in free practice

Reciprocal regulation

Lipid metabolism Practice Question

Lipid metabolism: Reciprocal regulation

Connect loss of CPT I inhibition to simultaneous fatty acid synthesis and mitochondrial oxidationIncluded in free practice

Uncoupling

Oxidative phosphorylation Practice Question

Oxidative phosphorylation: Uncoupling

Integrate changes in oxygen consumption, membrane potential, NADH oxidation, ATP synthesis, and heat productionIncluded in free practice