BIOD 101 Modules 1–6 & Final Exam —
100 Practice Questions with Answers
Module 1: Chemistry of Life & Cell Structure (Q1–Q18)
Q1. What are the six predominant elements in living organisms?
A. Carbon, hydrogen, oxygen, nitrogen, calcium, phosphate
B. Carbon, hydrogen, oxygen, iron, sodium, potassium
C. Hydrogen, oxygen, chlorine, sulfur, magnesium, zinc
D. Carbon, nitrogen, phosphorus, copper, iodine, selenium
Answer: A — The six predominant elements are oxygen, carbon, hydrogen, nitrogen,
calcium, and phosphate .
Q2. Essential elements are required for human life in large amounts, while trace elements
are required only in small quantities.
A. True
B. False
Answer: A — Essential elements are required in abundance; trace elements are required
only in small amounts .
Q3. A cation is a __________ charged ion, and an anion is a __________ charged ion.
A. Negatively; positively
B. Positively; negatively
C. Neutrally; positively
D. Positively; neutrally
Answer: B — Cations carry a positive charge; anions carry a negative charge .
Q4. Which type of bond is formed when electrons are shared between atoms?
A. Ionic bond
B. Covalent bond
C. Hydrogen bond
D. Peptide bond
Answer: B — Covalent bonds form when atoms share electrons .
Q5. Which of the following is NOT one of the four major biomacromolecules?
A. Proteins
B. Ribosomes
,C. Carbohydrates
D. Nucleic acids
Answer: B — The four biomacromolecules are carbohydrates, lipids, proteins, and nucleic
acids. Ribosomes are organelles, not macromolecules .
Q6. Why are lipids insoluble in water?
A. They contain polar phosphate groups
B. They are made mostly of non-polar hydrocarbon chains
C. They are too large to dissolve
D. They contain nitrogen groups
Answer: B — Lipids are insoluble because they consist primarily of non-polar hydrocarbon
chains, while water is polar .
Q7. What are the monomers that make up proteins?
A. Monosaccharides
B. Nucleotides
C. Amino acids
D. Fatty acids
Answer: C — Amino acids are the building blocks of proteins and are linked by peptide
bonds .
Q8. What type of bond holds amino acids together in a protein?
A. Hydrogen bond
B. Ionic bond
C. Peptide bond
D. Glycosidic bond
Answer: C — Peptide bonds form between the carboxyl group of one amino acid and the
amino group of another .
Q9. Which of the following is a monosaccharide?
A. Sucrose
B. Lactose
C. Glucose
D. Starch
Answer: C — Glucose is a monosaccharide. Sucrose and lactose are disaccharides; starch is
a polysaccharide .
Q10. A dehydration reaction involves the __________ of a water molecule when monomers
are joined together.
, A. Addition
B. Loss
C. Transfer
D. Breaking
Answer: B — Dehydration synthesis involves the loss of a water molecule to join
monomers .
Q11. DNA is a double-stranded helix held together by hydrogen bonds, while RNA is typically
a single strand.
A. True
B. False
Answer: A — DNA is double-stranded with hydrogen bonds between base pairs; RNA is
single-stranded .
Q12. What are the three parts of a nucleotide?
A. Phosphate group, 5-carbon sugar, nitrogenous base
B. Amino group, carboxyl group, R group
C. Glycerol, fatty acids, phosphate
D. Sugar, protein, lipid
Answer: A — A nucleotide consists of a phosphate group, a 5-carbon sugar, and a
nitrogenous base .
Q13. The head group of a phospholipid is __________, while the tail group is __________.
A. Hydrophobic; hydrophilic
B. Hydrophilic; hydrophobic
C. Polar; polar
D. Non-polar; non-polar
Answer: B — The phosphate head is hydrophilic (polar); the fatty acid tails are
hydrophobic (non-polar) .
Q14. When a cell is placed in a hypotonic solution, what happens?
A. The cell shrinks
B. The cell swells and may burst
C. No change occurs
D. The cell becomes rigid
Answer: B — Water flows into the cell, causing it to swell and potentially burst .
Q15. What is the function of the mitochondria?
100 Practice Questions with Answers
Module 1: Chemistry of Life & Cell Structure (Q1–Q18)
Q1. What are the six predominant elements in living organisms?
A. Carbon, hydrogen, oxygen, nitrogen, calcium, phosphate
B. Carbon, hydrogen, oxygen, iron, sodium, potassium
C. Hydrogen, oxygen, chlorine, sulfur, magnesium, zinc
D. Carbon, nitrogen, phosphorus, copper, iodine, selenium
Answer: A — The six predominant elements are oxygen, carbon, hydrogen, nitrogen,
calcium, and phosphate .
Q2. Essential elements are required for human life in large amounts, while trace elements
are required only in small quantities.
A. True
B. False
Answer: A — Essential elements are required in abundance; trace elements are required
only in small amounts .
Q3. A cation is a __________ charged ion, and an anion is a __________ charged ion.
A. Negatively; positively
B. Positively; negatively
C. Neutrally; positively
D. Positively; neutrally
Answer: B — Cations carry a positive charge; anions carry a negative charge .
Q4. Which type of bond is formed when electrons are shared between atoms?
A. Ionic bond
B. Covalent bond
C. Hydrogen bond
D. Peptide bond
Answer: B — Covalent bonds form when atoms share electrons .
Q5. Which of the following is NOT one of the four major biomacromolecules?
A. Proteins
B. Ribosomes
,C. Carbohydrates
D. Nucleic acids
Answer: B — The four biomacromolecules are carbohydrates, lipids, proteins, and nucleic
acids. Ribosomes are organelles, not macromolecules .
Q6. Why are lipids insoluble in water?
A. They contain polar phosphate groups
B. They are made mostly of non-polar hydrocarbon chains
C. They are too large to dissolve
D. They contain nitrogen groups
Answer: B — Lipids are insoluble because they consist primarily of non-polar hydrocarbon
chains, while water is polar .
Q7. What are the monomers that make up proteins?
A. Monosaccharides
B. Nucleotides
C. Amino acids
D. Fatty acids
Answer: C — Amino acids are the building blocks of proteins and are linked by peptide
bonds .
Q8. What type of bond holds amino acids together in a protein?
A. Hydrogen bond
B. Ionic bond
C. Peptide bond
D. Glycosidic bond
Answer: C — Peptide bonds form between the carboxyl group of one amino acid and the
amino group of another .
Q9. Which of the following is a monosaccharide?
A. Sucrose
B. Lactose
C. Glucose
D. Starch
Answer: C — Glucose is a monosaccharide. Sucrose and lactose are disaccharides; starch is
a polysaccharide .
Q10. A dehydration reaction involves the __________ of a water molecule when monomers
are joined together.
, A. Addition
B. Loss
C. Transfer
D. Breaking
Answer: B — Dehydration synthesis involves the loss of a water molecule to join
monomers .
Q11. DNA is a double-stranded helix held together by hydrogen bonds, while RNA is typically
a single strand.
A. True
B. False
Answer: A — DNA is double-stranded with hydrogen bonds between base pairs; RNA is
single-stranded .
Q12. What are the three parts of a nucleotide?
A. Phosphate group, 5-carbon sugar, nitrogenous base
B. Amino group, carboxyl group, R group
C. Glycerol, fatty acids, phosphate
D. Sugar, protein, lipid
Answer: A — A nucleotide consists of a phosphate group, a 5-carbon sugar, and a
nitrogenous base .
Q13. The head group of a phospholipid is __________, while the tail group is __________.
A. Hydrophobic; hydrophilic
B. Hydrophilic; hydrophobic
C. Polar; polar
D. Non-polar; non-polar
Answer: B — The phosphate head is hydrophilic (polar); the fatty acid tails are
hydrophobic (non-polar) .
Q14. When a cell is placed in a hypotonic solution, what happens?
A. The cell shrinks
B. The cell swells and may burst
C. No change occurs
D. The cell becomes rigid
Answer: B — Water flows into the cell, causing it to swell and potentially burst .
Q15. What is the function of the mitochondria?
