1|Page
WGU C785 OBJECTIVE ASSESSMENT FINAL NEWEST
2026/ 2027 ACTUAL EXAM TEST BANK| C785
BIOCHEMISTRY OA FINAL REVIEW WITH
COMPLETE 350 REAL EXAM QUESTIONS AND
CORRECT VERIFIED ANSWERS/ ALREADY GRADED
A+ (MOST RECENT!!)
A patient with a newly diagnosed metabolic disorder has markedly
reduced ATP production despite adequate oxygen availability. Testing
shows impaired function of the mitochondrial electron transport chain.
Which process is most directly responsible for establishing the proton
gradient used to generate ATP?
A. Glycolysis
B. Electron transport
C. Fermentation
D. Substrate-level phosphorylation - Correct Answer - B. Electron
transport
Electrons transferred through complexes of the electron transport chain
provide energy to pump H⁺ from the mitochondrial matrix into the
intermembrane space. The resulting electrochemical gradient drives ATP
synthase. Glycolysis produces ATP directly but does not establish the
mitochondrial proton gradient. Fermentation does not require the
electron transport chain.
A researcher replaces a nonpolar amino acid within the hydrophobic
interior of a protein with a charged amino acid. The protein subsequently
loses its normal three-dimensional structure. Which interaction was most
directly disrupted?
A. Hydrogen bonding
pg. 1
,2|Page
B. Peptide bonding
C. Hydrophobic interactions
D. Phosphodiester bonding - Correct Answer - C. Hydrophobic
interactions
Nonpolar amino-acid side chains tend to cluster away from water within
the protein interior. Replacing one with a charged, hydrophilic residue
can disrupt the hydrophobic core and destabilize tertiary structure.
Peptide bonds form the backbone and are not directly responsible for
this particular change.
A patient has severe hypoglycemia after prolonged fasting. The liver
begins producing glucose from lactate, glycerol, and glucogenic amino
acids. Which pathway is primarily responsible?
A. Glycogenesis
B. Glycolysis
C. Gluconeogenesis
D. Lipogenesis - Correct Answer - C. Gluconeogenesis
Gluconeogenesis synthesizes glucose from noncarbohydrate precursors,
particularly during fasting. Glycogenesis stores glucose as glycogen,
whereas glycolysis breaks glucose down. Lipogenesis promotes fatty-
acid synthesis.
An enzyme normally converts substrate X into product Y. A compound
structurally similar to X binds the enzyme's active site but is not
converted into product. What type of inhibition is occurring?
A. Competitive
B. Noncompetitive
C. Irreversible
pg. 2
,3|Page
D. Allosteric activation - Correct Answer - A. Competitive
A competitive inhibitor resembles the substrate and competes for the
enzyme's active site. Increasing substrate concentration can partially
overcome competitive inhibition. Noncompetitive inhibitors bind at a
site distinct from the active site and reduce enzyme activity without
directly competing for substrate binding.
A laboratory technician compares DNA and RNA molecules isolated
from a cell. Which characteristic correctly distinguishes DNA from
RNA?
A. DNA contains ribose
B. DNA contains uracil
C. DNA is composed of amino acids
D. DNA contains deoxyribose - Correct Answer - D.
DNA contains deoxyribose, whereas RNA contains ribose. DNA uses
thymine, while RNA uses uracil. Both are nucleic acids composed of
nucleotide subunits.
A patient consumes a meal containing a large amount of starch.
Digestion produces glucose molecules that enter the bloodstream. What
type of carbohydrate is starch?
A. Monosaccharide
B. Disaccharide
C. Polysaccharide
D. Nucleotide - Correct Answer - C. Polysaccharide
Starch is a polysaccharide composed of many glucose units. Glucose
itself is a monosaccharide. Lactose and sucrose are examples of
disaccharides.
pg. 3
, 4|Page
A genetic mutation changes one nucleotide in a DNA sequence but does
not alter the amino acid encoded by the resulting codon. Which mutation
type best describes this finding?
A. Silent
B. Missense
C. Nonsense
D. Frameshift - Correct Answer - A. Silent
A silent mutation changes the nucleotide sequence without changing the
encoded amino acid because the genetic code is redundant. A missense
mutation changes an amino acid, while a nonsense mutation produces a
premature stop codon. A frameshift results from insertion or deletion of
nucleotides not occurring in multiples of three.
During prolonged exercise, skeletal muscle requires rapid ATP
production. Oxygen delivery temporarily becomes insufficient for the
metabolic demand. Which pathway allows glycolysis to continue by
regenerating NAD⁺?
A. β-oxidation
B. Fermentation
C. Citric acid cycle
D. Oxidative phosphorylation - Correct Answer - B. Fermentation
During anaerobic conditions, pyruvate can be converted to lactate,
regenerating NAD⁺ from NADH. This permits glycolysis to continue
producing a small amount of ATP. The citric acid cycle and oxidative
phosphorylation depend much more directly on aerobic mitochondrial
metabolism.
pg. 4
WGU C785 OBJECTIVE ASSESSMENT FINAL NEWEST
2026/ 2027 ACTUAL EXAM TEST BANK| C785
BIOCHEMISTRY OA FINAL REVIEW WITH
COMPLETE 350 REAL EXAM QUESTIONS AND
CORRECT VERIFIED ANSWERS/ ALREADY GRADED
A+ (MOST RECENT!!)
A patient with a newly diagnosed metabolic disorder has markedly
reduced ATP production despite adequate oxygen availability. Testing
shows impaired function of the mitochondrial electron transport chain.
Which process is most directly responsible for establishing the proton
gradient used to generate ATP?
A. Glycolysis
B. Electron transport
C. Fermentation
D. Substrate-level phosphorylation - Correct Answer - B. Electron
transport
Electrons transferred through complexes of the electron transport chain
provide energy to pump H⁺ from the mitochondrial matrix into the
intermembrane space. The resulting electrochemical gradient drives ATP
synthase. Glycolysis produces ATP directly but does not establish the
mitochondrial proton gradient. Fermentation does not require the
electron transport chain.
A researcher replaces a nonpolar amino acid within the hydrophobic
interior of a protein with a charged amino acid. The protein subsequently
loses its normal three-dimensional structure. Which interaction was most
directly disrupted?
A. Hydrogen bonding
pg. 1
,2|Page
B. Peptide bonding
C. Hydrophobic interactions
D. Phosphodiester bonding - Correct Answer - C. Hydrophobic
interactions
Nonpolar amino-acid side chains tend to cluster away from water within
the protein interior. Replacing one with a charged, hydrophilic residue
can disrupt the hydrophobic core and destabilize tertiary structure.
Peptide bonds form the backbone and are not directly responsible for
this particular change.
A patient has severe hypoglycemia after prolonged fasting. The liver
begins producing glucose from lactate, glycerol, and glucogenic amino
acids. Which pathway is primarily responsible?
A. Glycogenesis
B. Glycolysis
C. Gluconeogenesis
D. Lipogenesis - Correct Answer - C. Gluconeogenesis
Gluconeogenesis synthesizes glucose from noncarbohydrate precursors,
particularly during fasting. Glycogenesis stores glucose as glycogen,
whereas glycolysis breaks glucose down. Lipogenesis promotes fatty-
acid synthesis.
An enzyme normally converts substrate X into product Y. A compound
structurally similar to X binds the enzyme's active site but is not
converted into product. What type of inhibition is occurring?
A. Competitive
B. Noncompetitive
C. Irreversible
pg. 2
,3|Page
D. Allosteric activation - Correct Answer - A. Competitive
A competitive inhibitor resembles the substrate and competes for the
enzyme's active site. Increasing substrate concentration can partially
overcome competitive inhibition. Noncompetitive inhibitors bind at a
site distinct from the active site and reduce enzyme activity without
directly competing for substrate binding.
A laboratory technician compares DNA and RNA molecules isolated
from a cell. Which characteristic correctly distinguishes DNA from
RNA?
A. DNA contains ribose
B. DNA contains uracil
C. DNA is composed of amino acids
D. DNA contains deoxyribose - Correct Answer - D.
DNA contains deoxyribose, whereas RNA contains ribose. DNA uses
thymine, while RNA uses uracil. Both are nucleic acids composed of
nucleotide subunits.
A patient consumes a meal containing a large amount of starch.
Digestion produces glucose molecules that enter the bloodstream. What
type of carbohydrate is starch?
A. Monosaccharide
B. Disaccharide
C. Polysaccharide
D. Nucleotide - Correct Answer - C. Polysaccharide
Starch is a polysaccharide composed of many glucose units. Glucose
itself is a monosaccharide. Lactose and sucrose are examples of
disaccharides.
pg. 3
, 4|Page
A genetic mutation changes one nucleotide in a DNA sequence but does
not alter the amino acid encoded by the resulting codon. Which mutation
type best describes this finding?
A. Silent
B. Missense
C. Nonsense
D. Frameshift - Correct Answer - A. Silent
A silent mutation changes the nucleotide sequence without changing the
encoded amino acid because the genetic code is redundant. A missense
mutation changes an amino acid, while a nonsense mutation produces a
premature stop codon. A frameshift results from insertion or deletion of
nucleotides not occurring in multiples of three.
During prolonged exercise, skeletal muscle requires rapid ATP
production. Oxygen delivery temporarily becomes insufficient for the
metabolic demand. Which pathway allows glycolysis to continue by
regenerating NAD⁺?
A. β-oxidation
B. Fermentation
C. Citric acid cycle
D. Oxidative phosphorylation - Correct Answer - B. Fermentation
During anaerobic conditions, pyruvate can be converted to lactate,
regenerating NAD⁺ from NADH. This permits glycolysis to continue
producing a small amount of ATP. The citric acid cycle and oxidative
phosphorylation depend much more directly on aerobic mitochondrial
metabolism.
pg. 4