,MODULE 1 — QUESTIONS 1–30
1. Which characteristic is shared by all living organisms?
A. They are multicellular
B. They maintain homeostasis
C. They perform photosynthesis
D. They require oxygen
Answer: B. They maintain homeostasis
Rationale: Homeostasis is the ability to maintain relatively stable internal conditions despite
changes in the external environment.
2. Which level of biological organization consists of two or more atoms chemically bonded
together?
A. Cell
B. Tissue
C. Molecule
D. Organ
Answer: C. Molecule
Rationale: A molecule consists of two or more atoms joined by chemical bonds.
3. The atomic number of an element represents the number of:
A. Neutrons
B. Protons
C. Electrons plus neutrons
D. Energy levels
Answer: B. Protons
Rationale: The atomic number is defined by the number of protons in the nucleus.
4. Which subatomic particle carries a negative charge?
,A. Proton
B. Neutron
C. Electron
D. Nucleus
Answer: C. Electron
Rationale: Electrons have a negative electrical charge, while protons are positive and neutrons
have no charge.
5. What type of bond involves the sharing of electrons between atoms?
A. Ionic bond
B. Covalent bond
C. Hydrogen bond
D. Peptide bond
Answer: B. Covalent bond
Rationale: Covalent bonds form when atoms share one or more pairs of electrons.
6. What happens when an atom gains or loses electrons?
A. It becomes an isotope
B. It becomes an ion
C. It becomes a molecule
D. Its atomic number changes
Answer: B. It becomes an ion
Rationale: Gaining or losing electrons produces an electrically charged atom called an ion.
7. Which property of water allows it to resist rapid changes in temperature?
A. Low density
B. High specific heat
C. Low polarity
D. Poor cohesion
Answer: B. High specific heat
, Rationale: Water requires substantial energy to change temperature, helping organisms
maintain relatively stable temperatures.
8. Which substance is considered acidic?
A. A substance with a pH of 2
B. A substance with a pH of 7
C. A substance with a pH of 9
D. A substance with a pH of 12
Answer: A. A substance with a pH of 2
Rationale: Acids have pH values below 7, while bases have pH values above 7.
9. Which macromolecule is primarily responsible for storing and transmitting hereditary
information?
A. Lipid
B. Protein
C. Nucleic acid
D. Carbohydrate
Answer: C. Nucleic acid
Rationale: DNA and RNA are nucleic acids involved in genetic information storage,
transmission, and expression.
10. Which macromolecule is the body's primary short-term source of energy?
A. Carbohydrates
B. Lipids
C. Proteins
D. Nucleic acids
Answer: A. Carbohydrates
Rationale: Carbohydrates can be rapidly broken down to provide glucose and other usable
energy sources.
1. Which characteristic is shared by all living organisms?
A. They are multicellular
B. They maintain homeostasis
C. They perform photosynthesis
D. They require oxygen
Answer: B. They maintain homeostasis
Rationale: Homeostasis is the ability to maintain relatively stable internal conditions despite
changes in the external environment.
2. Which level of biological organization consists of two or more atoms chemically bonded
together?
A. Cell
B. Tissue
C. Molecule
D. Organ
Answer: C. Molecule
Rationale: A molecule consists of two or more atoms joined by chemical bonds.
3. The atomic number of an element represents the number of:
A. Neutrons
B. Protons
C. Electrons plus neutrons
D. Energy levels
Answer: B. Protons
Rationale: The atomic number is defined by the number of protons in the nucleus.
4. Which subatomic particle carries a negative charge?
,A. Proton
B. Neutron
C. Electron
D. Nucleus
Answer: C. Electron
Rationale: Electrons have a negative electrical charge, while protons are positive and neutrons
have no charge.
5. What type of bond involves the sharing of electrons between atoms?
A. Ionic bond
B. Covalent bond
C. Hydrogen bond
D. Peptide bond
Answer: B. Covalent bond
Rationale: Covalent bonds form when atoms share one or more pairs of electrons.
6. What happens when an atom gains or loses electrons?
A. It becomes an isotope
B. It becomes an ion
C. It becomes a molecule
D. Its atomic number changes
Answer: B. It becomes an ion
Rationale: Gaining or losing electrons produces an electrically charged atom called an ion.
7. Which property of water allows it to resist rapid changes in temperature?
A. Low density
B. High specific heat
C. Low polarity
D. Poor cohesion
Answer: B. High specific heat
, Rationale: Water requires substantial energy to change temperature, helping organisms
maintain relatively stable temperatures.
8. Which substance is considered acidic?
A. A substance with a pH of 2
B. A substance with a pH of 7
C. A substance with a pH of 9
D. A substance with a pH of 12
Answer: A. A substance with a pH of 2
Rationale: Acids have pH values below 7, while bases have pH values above 7.
9. Which macromolecule is primarily responsible for storing and transmitting hereditary
information?
A. Lipid
B. Protein
C. Nucleic acid
D. Carbohydrate
Answer: C. Nucleic acid
Rationale: DNA and RNA are nucleic acids involved in genetic information storage,
transmission, and expression.
10. Which macromolecule is the body's primary short-term source of energy?
A. Carbohydrates
B. Lipids
C. Proteins
D. Nucleic acids
Answer: A. Carbohydrates
Rationale: Carbohydrates can be rapidly broken down to provide glucose and other usable
energy sources.