BIOD 210 — Genetics | Module 1 Exam Portage Learning | Latest 2026/2027 Update
BIOD 210 — Genetics | Module 1 Exam
Latest 2026/2027 Update | Portage Learning | Questions & Answers
Grade A | 100% Correct | Comprehensive 100-Question Exam
Exam Specifications: Exactly 100 questions across 8 sections | 35% recall, 45% application, 20% analysis | 65%
application-based, 35% direct recall. Each item includes four options (A–D), one correct answer marked [CORRECT],
and a detailed rationale with molecular genetics reasoning, process flow, and error analysis.
Section 1: Foundations of Genetics and Molecular Biology
Questions Q1–Q13 | Focus: Genetic Terminology, DNA Structure, RNA Types, and Central Dogma
Q1: Which term BEST describes the specific physical location of a gene on a chromosome?
A. Locus — the fixed physical location of a gene on a chromosome. [CORRECT]
B. Allele — a variant form of a gene.
C. Genotype — the genetic makeup of an organism.
D. Phenotype — the observable traits of an organism.
Correct Answer: A
Rationale: A locus is the specific, fixed physical location of a gene on a chromosome. An allele is a variant form of a gene,
genotype is the allele combination, and phenotype is the observable trait.
Q2: Which statement correctly distinguishes an allele from a gene?
A. A gene is a segment of DNA that codes for a product; an allele is one of two or more alternative forms
of that gene at the same locus. [CORRECT]
B. An allele is a segment of DNA; a gene is a protein product.
C. A gene is always dominant; an allele is always recessive.
D. Alleles and genes are identical terms.
Correct Answer: A
Rationale: A gene is a DNA segment encoding a product; alleles are alternative forms of that gene at the same locus (e.g., A
vs. B vs. O for ABO). The other options misstate these definitions.
Q3: Which term refers to the complete set of genetic material in an organism?
A. Genome — the complete set of genetic material (DNA or RNA) in an organism or cell. [CORRECT]
B. Karyotype — a photographed set of chromosomes.
C. Genotype — the allele combination at a locus.
D. Phenotype — the observable trait.
Correct Answer: A
Rationale: The genome is the complete set of genetic material in an organism. A karyotype is the visual display of
chromosomes; genotype is the allele combination; phenotype is the observable trait.
Q4: Which structural feature of DNA was correctly described by Watson and Crick?
Questions & Answers | Grade A | 100% Correct Page 1
,BIOD 210 — Genetics | Module 1 Exam Portage Learning | Latest 2026/2027 Update
A. A double helix of two antiparallel strands with complementary base pairs (A–T, G–C) connected by
hydrogen bonds, with a sugar-phosphate backbone. [CORRECT]
B. A single-stranded helix with random base pairing.
C. A triple helix with peptide backbones.
D. A linear molecule with no defined backbone.
Correct Answer: A
Rationale: Watson and Crick described DNA as a double helix of two antiparallel strands held together by complementary
base pairs (A–T, G–C) via hydrogen bonds, with sugar-phosphate backbones. The other options misstate DNA's structure.
Q5: Which bases are classified as purines in DNA?
A. Adenine and guanine (double-ring structures). [CORRECT]
B. Cytosine and thymine (single-ring structures).
C. Uracil and thymine only.
D. Adenine and cytosine only.
Correct Answer: A
Rationale: Purines (adenine, guanine) have a double-ring structure; pyrimidines (cytosine, thymine, uracil) have a single
ring. The other options mix purines and pyrimidines incorrectly.
Q6: Which bases are classified as pyrimidines?
A. Cytosine, thymine, and uracil (single-ring structures). [CORRECT]
B. Adenine and guanine.
C. Adenine and thymine.
D. Guanine and cytosine only.
Correct Answer: A
Rationale: Pyrimidines (cytosine, thymine, uracil) have a single-ring structure; purines (adenine, guanine) are double-ring.
The other options misclassify the bases.
Q7: Which type of RNA carries the genetic code from DNA to the ribosome for protein synthesis?
A. Messenger RNA (mRNA) — carries the codon sequence transcribed from DNA to the ribosome.
[CORRECT]
B. Transfer RNA (tRNA).
C. Ribosomal RNA (rRNA).
D. MicroRNA (miRNA).
Correct Answer: A
Rationale: mRNA carries the genetic message from DNA to the ribosome. tRNA delivers amino acids, rRNA forms the
ribosome, and miRNA regulates gene expression rather than carrying a coding message.
Q8: Which type of RNA delivers specific amino acids to the ribosome during translation?
A. Transfer RNA (tRNA) — carries a specific amino acid and matches its anticodon to the mRNA codon.
[CORRECT]
B. Messenger RNA (mRNA).
Questions & Answers | Grade A | 100% Correct Page 2
, BIOD 210 — Genetics | Module 1 Exam Portage Learning | Latest 2026/2027 Update
C. Ribosomal RNA (rRNA).
D. Small nuclear RNA (snRNA).
Correct Answer: A
Rationale: tRNA carries a specific amino acid to the ribosome and uses its anticodon to pair with the mRNA codon. mRNA
carries the message, rRNA forms the ribosome, snRNA splices introns.
Q9: Which RNA type is a structural and catalytic component of the ribosome?
A. Ribosomal RNA (rRNA) — combines with proteins to form ribosomes and catalyzes peptide bond
formation. [CORRECT]
B. Messenger RNA (mRNA).
C. Transfer RNA (tRNA).
D. MicroRNA (miRNA).
Correct Answer: A
Rationale: rRNA combines with ribosomal proteins to form the ribosome and catalyzes peptide bond formation (peptidyl
transferase activity). mRNA, tRNA, and miRNA have different roles.
Q10: Which statement BEST describes the central dogma of molecular biology?
A. Genetic information flows from DNA → RNA → protein (transcription then translation).
[CORRECT]
B. Protein → RNA → DNA.
C. RNA → DNA → protein.
D. DNA → protein (skipping RNA).
Correct Answer: A
Rationale: The central dogma states that information flows DNA → RNA → protein, via transcription and translation. The
other orderings reverse or skip steps and are incorrect.
Q11: Which nucleotide is found in RNA but NOT in DNA?
A. Uracil (replaces thymine in RNA). [CORRECT]
B. Thymine.
C. Adenine.
D. Guanine.
Correct Answer: A
Rationale: RNA contains uracil in place of thymine found in DNA. Adenine and guanine are shared by both DNA and
RNA; thymine is in DNA, not RNA.
Q12: Which sugar is found in the backbone of DNA, distinguishing it from RNA?
A. Deoxyribose (DNA) vs. ribose (RNA), where DNA lacks the 2' hydroxyl group present in RNA.
[CORRECT]
B. Glucose.
C. Ribose in both DNA and RNA.
D. Maltose.
Questions & Answers | Grade A | 100% Correct Page 3
BIOD 210 — Genetics | Module 1 Exam
Latest 2026/2027 Update | Portage Learning | Questions & Answers
Grade A | 100% Correct | Comprehensive 100-Question Exam
Exam Specifications: Exactly 100 questions across 8 sections | 35% recall, 45% application, 20% analysis | 65%
application-based, 35% direct recall. Each item includes four options (A–D), one correct answer marked [CORRECT],
and a detailed rationale with molecular genetics reasoning, process flow, and error analysis.
Section 1: Foundations of Genetics and Molecular Biology
Questions Q1–Q13 | Focus: Genetic Terminology, DNA Structure, RNA Types, and Central Dogma
Q1: Which term BEST describes the specific physical location of a gene on a chromosome?
A. Locus — the fixed physical location of a gene on a chromosome. [CORRECT]
B. Allele — a variant form of a gene.
C. Genotype — the genetic makeup of an organism.
D. Phenotype — the observable traits of an organism.
Correct Answer: A
Rationale: A locus is the specific, fixed physical location of a gene on a chromosome. An allele is a variant form of a gene,
genotype is the allele combination, and phenotype is the observable trait.
Q2: Which statement correctly distinguishes an allele from a gene?
A. A gene is a segment of DNA that codes for a product; an allele is one of two or more alternative forms
of that gene at the same locus. [CORRECT]
B. An allele is a segment of DNA; a gene is a protein product.
C. A gene is always dominant; an allele is always recessive.
D. Alleles and genes are identical terms.
Correct Answer: A
Rationale: A gene is a DNA segment encoding a product; alleles are alternative forms of that gene at the same locus (e.g., A
vs. B vs. O for ABO). The other options misstate these definitions.
Q3: Which term refers to the complete set of genetic material in an organism?
A. Genome — the complete set of genetic material (DNA or RNA) in an organism or cell. [CORRECT]
B. Karyotype — a photographed set of chromosomes.
C. Genotype — the allele combination at a locus.
D. Phenotype — the observable trait.
Correct Answer: A
Rationale: The genome is the complete set of genetic material in an organism. A karyotype is the visual display of
chromosomes; genotype is the allele combination; phenotype is the observable trait.
Q4: Which structural feature of DNA was correctly described by Watson and Crick?
Questions & Answers | Grade A | 100% Correct Page 1
,BIOD 210 — Genetics | Module 1 Exam Portage Learning | Latest 2026/2027 Update
A. A double helix of two antiparallel strands with complementary base pairs (A–T, G–C) connected by
hydrogen bonds, with a sugar-phosphate backbone. [CORRECT]
B. A single-stranded helix with random base pairing.
C. A triple helix with peptide backbones.
D. A linear molecule with no defined backbone.
Correct Answer: A
Rationale: Watson and Crick described DNA as a double helix of two antiparallel strands held together by complementary
base pairs (A–T, G–C) via hydrogen bonds, with sugar-phosphate backbones. The other options misstate DNA's structure.
Q5: Which bases are classified as purines in DNA?
A. Adenine and guanine (double-ring structures). [CORRECT]
B. Cytosine and thymine (single-ring structures).
C. Uracil and thymine only.
D. Adenine and cytosine only.
Correct Answer: A
Rationale: Purines (adenine, guanine) have a double-ring structure; pyrimidines (cytosine, thymine, uracil) have a single
ring. The other options mix purines and pyrimidines incorrectly.
Q6: Which bases are classified as pyrimidines?
A. Cytosine, thymine, and uracil (single-ring structures). [CORRECT]
B. Adenine and guanine.
C. Adenine and thymine.
D. Guanine and cytosine only.
Correct Answer: A
Rationale: Pyrimidines (cytosine, thymine, uracil) have a single-ring structure; purines (adenine, guanine) are double-ring.
The other options misclassify the bases.
Q7: Which type of RNA carries the genetic code from DNA to the ribosome for protein synthesis?
A. Messenger RNA (mRNA) — carries the codon sequence transcribed from DNA to the ribosome.
[CORRECT]
B. Transfer RNA (tRNA).
C. Ribosomal RNA (rRNA).
D. MicroRNA (miRNA).
Correct Answer: A
Rationale: mRNA carries the genetic message from DNA to the ribosome. tRNA delivers amino acids, rRNA forms the
ribosome, and miRNA regulates gene expression rather than carrying a coding message.
Q8: Which type of RNA delivers specific amino acids to the ribosome during translation?
A. Transfer RNA (tRNA) — carries a specific amino acid and matches its anticodon to the mRNA codon.
[CORRECT]
B. Messenger RNA (mRNA).
Questions & Answers | Grade A | 100% Correct Page 2
, BIOD 210 — Genetics | Module 1 Exam Portage Learning | Latest 2026/2027 Update
C. Ribosomal RNA (rRNA).
D. Small nuclear RNA (snRNA).
Correct Answer: A
Rationale: tRNA carries a specific amino acid to the ribosome and uses its anticodon to pair with the mRNA codon. mRNA
carries the message, rRNA forms the ribosome, snRNA splices introns.
Q9: Which RNA type is a structural and catalytic component of the ribosome?
A. Ribosomal RNA (rRNA) — combines with proteins to form ribosomes and catalyzes peptide bond
formation. [CORRECT]
B. Messenger RNA (mRNA).
C. Transfer RNA (tRNA).
D. MicroRNA (miRNA).
Correct Answer: A
Rationale: rRNA combines with ribosomal proteins to form the ribosome and catalyzes peptide bond formation (peptidyl
transferase activity). mRNA, tRNA, and miRNA have different roles.
Q10: Which statement BEST describes the central dogma of molecular biology?
A. Genetic information flows from DNA → RNA → protein (transcription then translation).
[CORRECT]
B. Protein → RNA → DNA.
C. RNA → DNA → protein.
D. DNA → protein (skipping RNA).
Correct Answer: A
Rationale: The central dogma states that information flows DNA → RNA → protein, via transcription and translation. The
other orderings reverse or skip steps and are incorrect.
Q11: Which nucleotide is found in RNA but NOT in DNA?
A. Uracil (replaces thymine in RNA). [CORRECT]
B. Thymine.
C. Adenine.
D. Guanine.
Correct Answer: A
Rationale: RNA contains uracil in place of thymine found in DNA. Adenine and guanine are shared by both DNA and
RNA; thymine is in DNA, not RNA.
Q12: Which sugar is found in the backbone of DNA, distinguishing it from RNA?
A. Deoxyribose (DNA) vs. ribose (RNA), where DNA lacks the 2' hydroxyl group present in RNA.
[CORRECT]
B. Glucose.
C. Ribose in both DNA and RNA.
D. Maltose.
Questions & Answers | Grade A | 100% Correct Page 3
