DENTAL ADMISSION TEST / ADA
DAT (Dental Admission Test) Exam 2026/2027 | ADA | Complete Review with
Questions & Verified Answers 2026/2027
A+
Complete Blueprint Coverage
A+ 4 100%
QUESTIONS VERIFIED CORE DOMAINS COVERED RATIONALES INCLUDED
CATEGORIES
Natural Sciences - Biology
Natural Sciences - General & Organic Chemistry
Perceptual Ability - Spatial Reasoning
Reading Comprehension
STUVIAACTUALEXAM
, Natural Sciences — Biology
Q1.
A cell is observed to have a high concentration of rough endoplasmic reticulum and an extensive Golgi apparatus. The cell is most likely
specialized for which function?
A. Synthesis and secretion of proteins
B. Rapid ATP production via oxidative phosphorylation
C. Storage of triglycerides
D. Detection of light stimuli
Correct Answer: A
Rationale: Rough ER is studded with ribosomes and synthesizes proteins destined for secretion or membranes; the Golgi modifies and packages those proteins. Cells rich in
both organelles are specialized for protein secretion.
Q2.
During DNA replication, the enzyme that joins Okazaki fragments on the lagging strand by forming phosphodiester bonds is:
A. Helicase
B. Primase
C. DNA ligase
D. Topoisomerase
Correct Answer: C
Rationale: DNA ligase seals nicks between adjacent Okazaki fragments by catalyzing the formation of phosphodiester bonds after RNA primers are removed and replaced with
DNA.
Q3.
In a pedigree analysis, an autosomal recessive trait appears in a child of two unaffected parents. The probability that the parents are both
heterozygous carriers is best explained by which inheritance pattern?
A. The trait appears in every generation.
B. The trait is transmitted only through the maternal line.
C. Only males express the trait.
D. The trait skips generations and affects males and females equally when both parents are carriers.
Correct Answer: D
Rationale: Autosomal recessive traits can skip generations; unaffected heterozygous parents each transmit a recessive allele, producing an affected homozygous recessive
child of either sex.
Q4.
A muscle cell needs to generate ATP under anaerobic conditions. Which pathway allows continued ATP production and regeneration of NAD+
from NADH?
A. Citric acid cycle
B. Lactic acid fermentation
C. Oxidative phosphorylation
D. Beta-oxidation of fatty acids
Correct Answer: B
Rationale: Under anaerobic conditions, pyruvate is reduced to lactate, regenerating NAD+ so that glycolysis can continue to produce a net of 2 ATP per glucose.
Q5.
The primary structure of a protein is disrupted by a mutation that substitutes one amino acid for another. Which level of protein structure is
directly defined by the sequence of amino acids?
A. Primary structure
B. Tertiary structure
C. Secondary structure
D. Quaternary structure
Correct Answer: A
Rationale: Primary structure is the linear sequence of amino acids linked by peptide bonds. Higher levels of structure depend on this sequence but are distinct from it.
Q6.
In the nephron, the majority of glucose reabsorption occurs in which segment under normal physiological conditions?
A. Descending limb of the loop of Henle
B. Distal convoluted tubule
C. Collecting duct
D. Proximal convoluted tubule
Correct Answer: D
Rationale: The proximal convoluted tubule reabsorbs essentially all filtered glucose via secondary active transport (SGLT) coupled to sodium, preventing glucose loss in urine
under normal conditions.
STUVIAACTUALEXAM Q1
Q2
Q3
Q4
Q5
Q6
, Natural Sciences — Biology
Q7.
A scientist observes that a population of bacteria becomes resistant to an antibiotic after several generations of exposure. The most accurate
evolutionary explanation is:
A. The antibiotic induced specific mutations that conferred resistance in every cell.
B. All bacteria simultaneously acquired resistance through Lamarckian inheritance.
C. Pre-existing resistant variants were selected for by the antibiotic pressure.
D. The antibiotic increased the overall mutation rate uniformly across the genome.
Correct Answer: C
Rationale: Natural selection acts on pre-existing variation. Rare resistant mutants survive and reproduce preferentially under antibiotic pressure, increasing the frequency of
resistance alleles.
Q8.
Which organelle is responsible for the degradation of damaged organelles and macromolecules via acid hydrolases?
A. Peroxisome
B. Lysosome
C. Mitochondrion
D. Nucleolus
Correct Answer: B
Rationale: Lysosomes contain acid hydrolases that break down proteins, lipids, nucleic acids, and damaged organelles delivered by autophagy or endocytosis.
Q9.
In meiosis, homologous chromosomes separate during which stage?
A. Anaphase of mitosis
B. Metaphase II of meiosis
C. Anaphase II of meiosis
D. Anaphase I of meiosis
Correct Answer: D
Rationale: In anaphase I, homologous chromosome pairs (tetrads) segregate to opposite poles. Sister chromatids separate in anaphase II.
Q10.
A patient has a deficiency in the enzyme that converts phenylalanine to tyrosine. Accumulation of phenylalanine and its metabolites
characterizes which disorder?
A. Phenylketonuria (PKU)
B. Tay-Sachs disease
C. Sickle cell anemia
D. Cystic fibrosis
Correct Answer: A
Rationale: PKU is caused by deficiency of phenylalanine hydroxylase, leading to elevated phenylalanine levels that can impair neurological development if untreated.
Q11.
The sliding filament theory of muscle contraction requires ATP for which specific step?
A. Binding of calcium to troponin
B. Release of myosin heads from actin and re-cocking of the myosin heads
C. Depolarization of the T-tubule
D. Opening of voltage-gated sodium channels
Correct Answer: B
Rationale: ATP binding causes myosin to detach from actin; subsequent hydrolysis of ATP cocks the myosin head into the high-energy conformation ready for the next power
stroke.
Q12.
In the lac operon of E. coli, the presence of lactose and absence of glucose leads to high expression of lac genes. The CAP-cAMP complex
acts as a:
A. Repressor that binds the operator
B. Sigma factor that replaces the normal sigma
C. Positive regulator that enhances RNA polymerase binding at the promoter
D. Ribosome binding inhibitor
Correct Answer: C
Rationale: When glucose is low, cAMP levels rise and CAP-cAMP binds upstream of the lac promoter, facilitating RNA polymerase recruitment and increasing transcription
(positive regulation).
STUVIAACTUALEXAM Q10
Q11
Q12
Q7
Q8
Q9
DAT (Dental Admission Test) Exam 2026/2027 | ADA | Complete Review with
Questions & Verified Answers 2026/2027
A+
Complete Blueprint Coverage
A+ 4 100%
QUESTIONS VERIFIED CORE DOMAINS COVERED RATIONALES INCLUDED
CATEGORIES
Natural Sciences - Biology
Natural Sciences - General & Organic Chemistry
Perceptual Ability - Spatial Reasoning
Reading Comprehension
STUVIAACTUALEXAM
, Natural Sciences — Biology
Q1.
A cell is observed to have a high concentration of rough endoplasmic reticulum and an extensive Golgi apparatus. The cell is most likely
specialized for which function?
A. Synthesis and secretion of proteins
B. Rapid ATP production via oxidative phosphorylation
C. Storage of triglycerides
D. Detection of light stimuli
Correct Answer: A
Rationale: Rough ER is studded with ribosomes and synthesizes proteins destined for secretion or membranes; the Golgi modifies and packages those proteins. Cells rich in
both organelles are specialized for protein secretion.
Q2.
During DNA replication, the enzyme that joins Okazaki fragments on the lagging strand by forming phosphodiester bonds is:
A. Helicase
B. Primase
C. DNA ligase
D. Topoisomerase
Correct Answer: C
Rationale: DNA ligase seals nicks between adjacent Okazaki fragments by catalyzing the formation of phosphodiester bonds after RNA primers are removed and replaced with
DNA.
Q3.
In a pedigree analysis, an autosomal recessive trait appears in a child of two unaffected parents. The probability that the parents are both
heterozygous carriers is best explained by which inheritance pattern?
A. The trait appears in every generation.
B. The trait is transmitted only through the maternal line.
C. Only males express the trait.
D. The trait skips generations and affects males and females equally when both parents are carriers.
Correct Answer: D
Rationale: Autosomal recessive traits can skip generations; unaffected heterozygous parents each transmit a recessive allele, producing an affected homozygous recessive
child of either sex.
Q4.
A muscle cell needs to generate ATP under anaerobic conditions. Which pathway allows continued ATP production and regeneration of NAD+
from NADH?
A. Citric acid cycle
B. Lactic acid fermentation
C. Oxidative phosphorylation
D. Beta-oxidation of fatty acids
Correct Answer: B
Rationale: Under anaerobic conditions, pyruvate is reduced to lactate, regenerating NAD+ so that glycolysis can continue to produce a net of 2 ATP per glucose.
Q5.
The primary structure of a protein is disrupted by a mutation that substitutes one amino acid for another. Which level of protein structure is
directly defined by the sequence of amino acids?
A. Primary structure
B. Tertiary structure
C. Secondary structure
D. Quaternary structure
Correct Answer: A
Rationale: Primary structure is the linear sequence of amino acids linked by peptide bonds. Higher levels of structure depend on this sequence but are distinct from it.
Q6.
In the nephron, the majority of glucose reabsorption occurs in which segment under normal physiological conditions?
A. Descending limb of the loop of Henle
B. Distal convoluted tubule
C. Collecting duct
D. Proximal convoluted tubule
Correct Answer: D
Rationale: The proximal convoluted tubule reabsorbs essentially all filtered glucose via secondary active transport (SGLT) coupled to sodium, preventing glucose loss in urine
under normal conditions.
STUVIAACTUALEXAM Q1
Q2
Q3
Q4
Q5
Q6
, Natural Sciences — Biology
Q7.
A scientist observes that a population of bacteria becomes resistant to an antibiotic after several generations of exposure. The most accurate
evolutionary explanation is:
A. The antibiotic induced specific mutations that conferred resistance in every cell.
B. All bacteria simultaneously acquired resistance through Lamarckian inheritance.
C. Pre-existing resistant variants were selected for by the antibiotic pressure.
D. The antibiotic increased the overall mutation rate uniformly across the genome.
Correct Answer: C
Rationale: Natural selection acts on pre-existing variation. Rare resistant mutants survive and reproduce preferentially under antibiotic pressure, increasing the frequency of
resistance alleles.
Q8.
Which organelle is responsible for the degradation of damaged organelles and macromolecules via acid hydrolases?
A. Peroxisome
B. Lysosome
C. Mitochondrion
D. Nucleolus
Correct Answer: B
Rationale: Lysosomes contain acid hydrolases that break down proteins, lipids, nucleic acids, and damaged organelles delivered by autophagy or endocytosis.
Q9.
In meiosis, homologous chromosomes separate during which stage?
A. Anaphase of mitosis
B. Metaphase II of meiosis
C. Anaphase II of meiosis
D. Anaphase I of meiosis
Correct Answer: D
Rationale: In anaphase I, homologous chromosome pairs (tetrads) segregate to opposite poles. Sister chromatids separate in anaphase II.
Q10.
A patient has a deficiency in the enzyme that converts phenylalanine to tyrosine. Accumulation of phenylalanine and its metabolites
characterizes which disorder?
A. Phenylketonuria (PKU)
B. Tay-Sachs disease
C. Sickle cell anemia
D. Cystic fibrosis
Correct Answer: A
Rationale: PKU is caused by deficiency of phenylalanine hydroxylase, leading to elevated phenylalanine levels that can impair neurological development if untreated.
Q11.
The sliding filament theory of muscle contraction requires ATP for which specific step?
A. Binding of calcium to troponin
B. Release of myosin heads from actin and re-cocking of the myosin heads
C. Depolarization of the T-tubule
D. Opening of voltage-gated sodium channels
Correct Answer: B
Rationale: ATP binding causes myosin to detach from actin; subsequent hydrolysis of ATP cocks the myosin head into the high-energy conformation ready for the next power
stroke.
Q12.
In the lac operon of E. coli, the presence of lactose and absence of glucose leads to high expression of lac genes. The CAP-cAMP complex
acts as a:
A. Repressor that binds the operator
B. Sigma factor that replaces the normal sigma
C. Positive regulator that enhances RNA polymerase binding at the promoter
D. Ribosome binding inhibitor
Correct Answer: C
Rationale: When glucose is low, cAMP levels rise and CAP-cAMP binds upstream of the lac promoter, facilitating RNA polymerase recruitment and increasing transcription
(positive regulation).
STUVIAACTUALEXAM Q10
Q11
Q12
Q7
Q8
Q9
