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AP BIOLOGY FIRST SEMESTER
FINAL ACTUAL EXAM 2026 | 150
QUESTIONS AND VERIFIED
ANSWERS |ALREADY A GRADED |
NEW AND REVISED
1. A biologist notes that water has a high specific heat, allowing
organisms to maintain stable internal temperatures. This property
is primarily due to
A. water’s polarity
B. water’s density in solid form
C. hydrogen bonding between water molecules
D. water’s ability to dissolve ions
Rationale: Hydrogen bonds absorb and release heat slowly,
stabilizing temperature.
2. Which level of biological organization includes all abiotic factors
in addition to living organisms?
A. Population
B. Community
C. Ecosystem
D. Biosphere
Rationale: Ecosystems include living (biotic) and nonliving
(abiotic) components.
3. A solution with a pH of 3 is how many times more acidic than a
solution with a pH of 5?
A. 2 times
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B. 10 times
C. 100 times
D. 1,000 times
Rationale: Each pH unit represents a tenfold change in
hydrogen ion concentration.
4. Which element is essential for the formation of disulfide bridges in
proteins?
A. Carbon
B. Nitrogen
C. Sulfur
D. Phosphorus
Rationale: Disulfide bonds form between sulfur-containing
amino acids.
5. The monomers of carbohydrates are
A. fatty acids
B. monosaccharides
C. amino acids
D. nucleotides
Rationale: Carbohydrates are polymers built from
monosaccharide units.
6. Which macromolecule is primarily responsible for storing genetic
information?
A. Proteins
B. Lipids
C. Carbohydrates
D. Nucleic acids
Rationale: DNA and RNA store and transmit genetic
information.
7. A student performs a Benedict’s test on a solution, and it turns
brick red. This indicates the presence of
A. starch
B. reducing sugars
C. proteins
D. lipids
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Rationale: Benedict’s reagent detects reducing sugars like
glucose.
8. Which bond forms between amino acids during protein synthesis?
A. Hydrogen bond
B. Peptide bond
C. Ionic bond
D. Disulfide bond
Rationale: Peptide bonds link amino acids into polypeptides.
9. An enzyme increases the rate of a chemical reaction by
A. increasing activation energy
B. changing reaction products
C. lowering activation energy
D. increasing substrate concentration
Rationale: Enzymes speed reactions by reducing the energy
barrier.
10. Which factor would most likely cause an enzyme to
denature?
A. Increased substrate concentration
B. Extreme pH
C. Presence of cofactors
D. Competitive inhibition
Rationale: Extreme pH disrupts protein structure.
11. The fluid mosaic model describes
A. the rigidity of cell membranes
B. carbohydrate distribution in cells
C. proteins embedded in a phospholipid bilayer
D. cell wall structure
Rationale: Membranes consist of moving phospholipids with
embedded proteins.
12. Which organelle is the primary site of ATP synthesis in
eukaryotic cells?
A. Ribosome
B. Nucleus
C. Mitochondrion
AP BIOLOGY FIRST SEMESTER
FINAL ACTUAL EXAM 2026 | 150
QUESTIONS AND VERIFIED
ANSWERS |ALREADY A GRADED |
NEW AND REVISED
1. A biologist notes that water has a high specific heat, allowing
organisms to maintain stable internal temperatures. This property
is primarily due to
A. water’s polarity
B. water’s density in solid form
C. hydrogen bonding between water molecules
D. water’s ability to dissolve ions
Rationale: Hydrogen bonds absorb and release heat slowly,
stabilizing temperature.
2. Which level of biological organization includes all abiotic factors
in addition to living organisms?
A. Population
B. Community
C. Ecosystem
D. Biosphere
Rationale: Ecosystems include living (biotic) and nonliving
(abiotic) components.
3. A solution with a pH of 3 is how many times more acidic than a
solution with a pH of 5?
A. 2 times
,2|Page
B. 10 times
C. 100 times
D. 1,000 times
Rationale: Each pH unit represents a tenfold change in
hydrogen ion concentration.
4. Which element is essential for the formation of disulfide bridges in
proteins?
A. Carbon
B. Nitrogen
C. Sulfur
D. Phosphorus
Rationale: Disulfide bonds form between sulfur-containing
amino acids.
5. The monomers of carbohydrates are
A. fatty acids
B. monosaccharides
C. amino acids
D. nucleotides
Rationale: Carbohydrates are polymers built from
monosaccharide units.
6. Which macromolecule is primarily responsible for storing genetic
information?
A. Proteins
B. Lipids
C. Carbohydrates
D. Nucleic acids
Rationale: DNA and RNA store and transmit genetic
information.
7. A student performs a Benedict’s test on a solution, and it turns
brick red. This indicates the presence of
A. starch
B. reducing sugars
C. proteins
D. lipids
, 3|Page
Rationale: Benedict’s reagent detects reducing sugars like
glucose.
8. Which bond forms between amino acids during protein synthesis?
A. Hydrogen bond
B. Peptide bond
C. Ionic bond
D. Disulfide bond
Rationale: Peptide bonds link amino acids into polypeptides.
9. An enzyme increases the rate of a chemical reaction by
A. increasing activation energy
B. changing reaction products
C. lowering activation energy
D. increasing substrate concentration
Rationale: Enzymes speed reactions by reducing the energy
barrier.
10. Which factor would most likely cause an enzyme to
denature?
A. Increased substrate concentration
B. Extreme pH
C. Presence of cofactors
D. Competitive inhibition
Rationale: Extreme pH disrupts protein structure.
11. The fluid mosaic model describes
A. the rigidity of cell membranes
B. carbohydrate distribution in cells
C. proteins embedded in a phospholipid bilayer
D. cell wall structure
Rationale: Membranes consist of moving phospholipids with
embedded proteins.
12. Which organelle is the primary site of ATP synthesis in
eukaryotic cells?
A. Ribosome
B. Nucleus
C. Mitochondrion
