UVIC BIOLOGY 186 ACTUAL 2025/2026 QUESTIONS AND
100% CORRECT ANSWERS
1. Organic chemistry is currently defined as:
a) The study of compounds made only by living cells
b) The study of carbon compounds
c) The study of natural compounds
d) The study of hydrocarbons
Answer: b) The study of carbon compounds
Explanation: Organic chemistry is the study of carbon-containing compounds. While many organic
compounds are found in living organisms, the field also includes synthetic carbon compounds. Carbon's
unique bonding properties allow for the vast diversity of organic molecules .
2. Which of the following hydrocarbons has a double bond in its carbon skeleton?
a) C₃H₈
b) C₂H₆
c) C₂H₄
d) C₂H₂
Answer: c) C₂H₄
Explanation: C₂H₄ is ethene (ethylene), which contains a carbon-carbon double bond. C₃H₈ (propane) and
C₂H₆ (ethane) are alkanes with only single bonds, while C₂H₂ (ethyne) contains a triple bond .
,3. Which chemical group is most likely to be responsible for an organic molecule behaving as a base?
a) Hydroxyl
b) Carbonyl
c) Amino
d) Phosphate
Answer: c) Amino
Explanation: The amino group (-NH₂) can accept a proton (H⁺), making it basic. Hydroxyl groups are polar
but not basic, carbonyl groups are neutral, and phosphate groups are acidic .
4. Which of the following categories includes all others in the list?
a) Monosaccharide
b) Polysaccharide
c) Starch
d) Carbohydrate
Answer: d) Carbohydrate
Explanation: Carbohydrates are the broad class of organic molecules that includes monosaccharides
(simple sugars), polysaccharides (complex sugars), and specific polysaccharides like starch .
5. The enzyme amylase can break glycosidic linkages between glucose monomers only if the monomers
are in the α form. Which of the following could amylase break down?
a) Glycogen, starch, and amylopectin
b) Glycogen and cellulose
c) Cellulose and chitin
,d) Starch, cellulose, and chitin
Answer: a) Glycogen, starch, and amylopectin
Explanation: Amylase breaks α-1,4 glycosidic linkages found in starch, glycogen, and amylopectin.
Cellulose contains β-1,4 linkages which amylase cannot break, which is why humans cannot digest
cellulose .
6. Which of the following statements is true of unsaturated fats?
a) They are more common in animals than in plants
b) They have double bonds in the carbon chains of their fatty acids
c) They generally solidify at room temperature
d) They contain more hydrogen than saturated fats with the same number of carbon atoms
Answer: b) They have double bonds in the carbon chains of their fatty acids
Explanation: Unsaturated fats contain one or more double bonds in their fatty acid chains, creating kinks
that prevent tight packing. This is why they are liquid at room temperature (oils) and are more common
in plants .
7. The structural level of a protein least affected by a disruption in hydrogen bonding is the:
a) Primary level
b) Secondary level
c) Tertiary level
d) Quaternary level
Answer: a) Primary level
, Explanation: The primary structure is the sequence of amino acids held by covalent peptide bonds,
which are not affected by hydrogen bond disruption. Secondary, tertiary, and quaternary structures all
rely heavily on hydrogen bonding .
8. The molecular formula for glucose is C₆H₁₂O₆. What would be the molecular formula for a polymer
made by linking 10 glucose molecules together by dehydration reactions?
a) C₆₀H₁₂₀O₆₀
b) C₆₀H₁₀₂O₅₁
c) C₆₀H₁₀₀O₅₀
d) C₆₀H₁₁₁O₅₁
Answer: b) C₆₀H₁₀₂O₅₁
Explanation: Each dehydration reaction removes one H₂O molecule. Linking 10 glucose molecules
requires 9 dehydration reactions, removing 9 H₂O molecules (9×H₂O = H₁₈O₉). Subtract this from the sum
of 10 glucose molecules (C₆₀H₁₂₀O₆₀) to get C₆₀H₁₀₂O₅₁ .
9. which of the following pairs of base sequences could form a short stretch of a normal double helix of
DNA?
a) 5'-purine-pyrimidine-purine-pyrimidine-3' with 3'-purine-pyrimidine-purine-pyrimidine-5'
b) 5'-AGCT-3' with 5'-GCAT-3'
c) 5'-ATGC-3' with 5'-GCAT-3'
d) All of these are correct
Answer: c) 5'-ATGC-3' with 5'-GCAT-3'
Explanation: In DNA, A pairs with T and G pairs with C. The complementary strand runs antiparallel (3' to
5'). Option c shows complementary base pairing: A with T, T with A, G with C, C with G, with the second
strand written 5' to 3' as GCAT .
100% CORRECT ANSWERS
1. Organic chemistry is currently defined as:
a) The study of compounds made only by living cells
b) The study of carbon compounds
c) The study of natural compounds
d) The study of hydrocarbons
Answer: b) The study of carbon compounds
Explanation: Organic chemistry is the study of carbon-containing compounds. While many organic
compounds are found in living organisms, the field also includes synthetic carbon compounds. Carbon's
unique bonding properties allow for the vast diversity of organic molecules .
2. Which of the following hydrocarbons has a double bond in its carbon skeleton?
a) C₃H₈
b) C₂H₆
c) C₂H₄
d) C₂H₂
Answer: c) C₂H₄
Explanation: C₂H₄ is ethene (ethylene), which contains a carbon-carbon double bond. C₃H₈ (propane) and
C₂H₆ (ethane) are alkanes with only single bonds, while C₂H₂ (ethyne) contains a triple bond .
,3. Which chemical group is most likely to be responsible for an organic molecule behaving as a base?
a) Hydroxyl
b) Carbonyl
c) Amino
d) Phosphate
Answer: c) Amino
Explanation: The amino group (-NH₂) can accept a proton (H⁺), making it basic. Hydroxyl groups are polar
but not basic, carbonyl groups are neutral, and phosphate groups are acidic .
4. Which of the following categories includes all others in the list?
a) Monosaccharide
b) Polysaccharide
c) Starch
d) Carbohydrate
Answer: d) Carbohydrate
Explanation: Carbohydrates are the broad class of organic molecules that includes monosaccharides
(simple sugars), polysaccharides (complex sugars), and specific polysaccharides like starch .
5. The enzyme amylase can break glycosidic linkages between glucose monomers only if the monomers
are in the α form. Which of the following could amylase break down?
a) Glycogen, starch, and amylopectin
b) Glycogen and cellulose
c) Cellulose and chitin
,d) Starch, cellulose, and chitin
Answer: a) Glycogen, starch, and amylopectin
Explanation: Amylase breaks α-1,4 glycosidic linkages found in starch, glycogen, and amylopectin.
Cellulose contains β-1,4 linkages which amylase cannot break, which is why humans cannot digest
cellulose .
6. Which of the following statements is true of unsaturated fats?
a) They are more common in animals than in plants
b) They have double bonds in the carbon chains of their fatty acids
c) They generally solidify at room temperature
d) They contain more hydrogen than saturated fats with the same number of carbon atoms
Answer: b) They have double bonds in the carbon chains of their fatty acids
Explanation: Unsaturated fats contain one or more double bonds in their fatty acid chains, creating kinks
that prevent tight packing. This is why they are liquid at room temperature (oils) and are more common
in plants .
7. The structural level of a protein least affected by a disruption in hydrogen bonding is the:
a) Primary level
b) Secondary level
c) Tertiary level
d) Quaternary level
Answer: a) Primary level
, Explanation: The primary structure is the sequence of amino acids held by covalent peptide bonds,
which are not affected by hydrogen bond disruption. Secondary, tertiary, and quaternary structures all
rely heavily on hydrogen bonding .
8. The molecular formula for glucose is C₆H₁₂O₆. What would be the molecular formula for a polymer
made by linking 10 glucose molecules together by dehydration reactions?
a) C₆₀H₁₂₀O₆₀
b) C₆₀H₁₀₂O₅₁
c) C₆₀H₁₀₀O₅₀
d) C₆₀H₁₁₁O₅₁
Answer: b) C₆₀H₁₀₂O₅₁
Explanation: Each dehydration reaction removes one H₂O molecule. Linking 10 glucose molecules
requires 9 dehydration reactions, removing 9 H₂O molecules (9×H₂O = H₁₈O₉). Subtract this from the sum
of 10 glucose molecules (C₆₀H₁₂₀O₆₀) to get C₆₀H₁₀₂O₅₁ .
9. which of the following pairs of base sequences could form a short stretch of a normal double helix of
DNA?
a) 5'-purine-pyrimidine-purine-pyrimidine-3' with 3'-purine-pyrimidine-purine-pyrimidine-5'
b) 5'-AGCT-3' with 5'-GCAT-3'
c) 5'-ATGC-3' with 5'-GCAT-3'
d) All of these are correct
Answer: c) 5'-ATGC-3' with 5'-GCAT-3'
Explanation: In DNA, A pairs with T and G pairs with C. The complementary strand runs antiparallel (3' to
5'). Option c shows complementary base pairing: A with T, T with A, G with C, C with G, with the second
strand written 5' to 3' as GCAT .
