BIOL180 Practice Exam 2
Biomolecules and Enzymes Questions
And Correct Answers (Verified
Answers) Plus Rationales 2026 Q&A |
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1. Which statement best describes a biological macromolecule?
A. A molecule found only inside the nucleus
B. A molecule that always contains carbon and nitrogen
C. A large or complex molecule that performs important biological
functions
D. A molecule that cannot interact with water
Answer: C. A large or complex molecule that performs important
biological functions
Rationale: Biological macromolecules include carbohydrates, lipids,
proteins, and nucleic acids. They have diverse structures and
functions, including energy storage, structural support, catalysis,
signaling, and information storage. Not every macromolecule contains
exactly the same elements, and many can interact extensively with
water.
2. Which four categories represent the major classes of biological
macromolecules?
A. Vitamins, minerals, salts, and water
B. Carbohydrates, lipids, proteins, and nucleic acids
,C. Sugars, steroids, enzymes, and vitamins
D. DNA, RNA, ATP, and glucose
Answer: B. Carbohydrates, lipids, proteins, and nucleic acids
Rationale: The four major classes of biological macromolecules are
carbohydrates, lipids, proteins, and nucleic acids. Although ATP and
other compounds are biologically important, they are not one of the
four broad macromolecule categories.
3. Which process joins monomers together by removing a molecule
of water?
A. Dehydration synthesis
B. Hydrolysis
C. Oxidation
D. Diffusion
Answer: A. Dehydration synthesis
Rationale: Dehydration synthesis, also called a condensation reaction,
forms a covalent bond between molecules while removing water. It is a
major mechanism for building polymers from smaller subunits.
Hydrolysis reverses this process by adding water to break a bond.
4. Which process uses water to break a covalent bond between
biological molecules?
A. Dehydration synthesis
B. Reduction
C. Polymerization
D. Hydrolysis
Answer: D. Hydrolysis
,Rationale: Hydrolysis means “splitting with water.” Water participates
in breaking covalent bonds within larger molecules or polymers.
Digestion frequently relies on hydrolysis reactions to convert
macromolecules into smaller molecules that can be absorbed.
5. Which element is particularly characteristic of carbohydrates?
A. Phosphorus
B. Carbon
C. Iron
D. Sulfur
Answer: B. Carbon
Rationale: Carbohydrates are organic molecules composed primarily of
carbon, hydrogen, and oxygen. A common approximate representation
is a carbon-to-hydrogen-to-oxygen ratio of 1:2:1, although this pattern
does not apply perfectly to every carbohydrate.
6. What is the basic monomer of a carbohydrate polymer?
A. Amino acid
B. Nucleotide
C. Fatty acid
D. Monosaccharide
Answer: D. Monosaccharide
Rationale: Monosaccharides are simple sugars and serve as the basic
building blocks of many carbohydrates. Glucose, fructose, and
galactose are examples. Disaccharides contain two monosaccharides,
while polysaccharides contain many sugar units.
7. Which molecule is a monosaccharide?
, A. Glucose
B. Glycogen
C. Cellulose
D. Starch
Answer: A. Glucose
Rationale: Glucose is a six-carbon monosaccharide that plays a central
role in cellular energy metabolism. Starch, glycogen, and cellulose are
polysaccharides composed of many glucose units connected by
different types of glycosidic bonds.
8. What is the primary function of carbohydrates in many cells?
A. Store genetic information
B. Form antibodies
C. Provide and store chemical energy
D. Catalyze every cellular reaction
Answer: C. Provide and store chemical energy
Rationale: Carbohydrates are important energy sources and can also
function in energy storage. Glucose is commonly metabolized to
generate ATP, while starch in plants and glycogen in animals provide
forms of stored carbohydrate energy.
9. Which carbohydrate is the primary storage polysaccharide in
animals?
A. Cellulose
B. Glycogen
C. Starch
D. Chitin
Answer: B. Glycogen
Biomolecules and Enzymes Questions
And Correct Answers (Verified
Answers) Plus Rationales 2026 Q&A |
Instant Download Pdf
1. Which statement best describes a biological macromolecule?
A. A molecule found only inside the nucleus
B. A molecule that always contains carbon and nitrogen
C. A large or complex molecule that performs important biological
functions
D. A molecule that cannot interact with water
Answer: C. A large or complex molecule that performs important
biological functions
Rationale: Biological macromolecules include carbohydrates, lipids,
proteins, and nucleic acids. They have diverse structures and
functions, including energy storage, structural support, catalysis,
signaling, and information storage. Not every macromolecule contains
exactly the same elements, and many can interact extensively with
water.
2. Which four categories represent the major classes of biological
macromolecules?
A. Vitamins, minerals, salts, and water
B. Carbohydrates, lipids, proteins, and nucleic acids
,C. Sugars, steroids, enzymes, and vitamins
D. DNA, RNA, ATP, and glucose
Answer: B. Carbohydrates, lipids, proteins, and nucleic acids
Rationale: The four major classes of biological macromolecules are
carbohydrates, lipids, proteins, and nucleic acids. Although ATP and
other compounds are biologically important, they are not one of the
four broad macromolecule categories.
3. Which process joins monomers together by removing a molecule
of water?
A. Dehydration synthesis
B. Hydrolysis
C. Oxidation
D. Diffusion
Answer: A. Dehydration synthesis
Rationale: Dehydration synthesis, also called a condensation reaction,
forms a covalent bond between molecules while removing water. It is a
major mechanism for building polymers from smaller subunits.
Hydrolysis reverses this process by adding water to break a bond.
4. Which process uses water to break a covalent bond between
biological molecules?
A. Dehydration synthesis
B. Reduction
C. Polymerization
D. Hydrolysis
Answer: D. Hydrolysis
,Rationale: Hydrolysis means “splitting with water.” Water participates
in breaking covalent bonds within larger molecules or polymers.
Digestion frequently relies on hydrolysis reactions to convert
macromolecules into smaller molecules that can be absorbed.
5. Which element is particularly characteristic of carbohydrates?
A. Phosphorus
B. Carbon
C. Iron
D. Sulfur
Answer: B. Carbon
Rationale: Carbohydrates are organic molecules composed primarily of
carbon, hydrogen, and oxygen. A common approximate representation
is a carbon-to-hydrogen-to-oxygen ratio of 1:2:1, although this pattern
does not apply perfectly to every carbohydrate.
6. What is the basic monomer of a carbohydrate polymer?
A. Amino acid
B. Nucleotide
C. Fatty acid
D. Monosaccharide
Answer: D. Monosaccharide
Rationale: Monosaccharides are simple sugars and serve as the basic
building blocks of many carbohydrates. Glucose, fructose, and
galactose are examples. Disaccharides contain two monosaccharides,
while polysaccharides contain many sugar units.
7. Which molecule is a monosaccharide?
, A. Glucose
B. Glycogen
C. Cellulose
D. Starch
Answer: A. Glucose
Rationale: Glucose is a six-carbon monosaccharide that plays a central
role in cellular energy metabolism. Starch, glycogen, and cellulose are
polysaccharides composed of many glucose units connected by
different types of glycosidic bonds.
8. What is the primary function of carbohydrates in many cells?
A. Store genetic information
B. Form antibodies
C. Provide and store chemical energy
D. Catalyze every cellular reaction
Answer: C. Provide and store chemical energy
Rationale: Carbohydrates are important energy sources and can also
function in energy storage. Glucose is commonly metabolized to
generate ATP, while starch in plants and glycogen in animals provide
forms of stored carbohydrate energy.
9. Which carbohydrate is the primary storage polysaccharide in
animals?
A. Cellulose
B. Glycogen
C. Starch
D. Chitin
Answer: B. Glycogen
