Exam 1 Review Questions and Answers
Fundamentals of Life and Chemistry
1. Scientific Method and Characteristics of Life
Question 1:
Which of the following is NOT one of the basic characteristics of life?
A) Response to stimuli
B) Growth and development
C) Being composed only of inorganic molecules
D) Reproduction
Answer: C) Being composed only of inorganic molecules
Living organisms are primarily composed of organic molecules (carbon-based) such
as proteins, carbohydrates, lipids, and nucleic acids.
Question 2:
The correct order of the scientific method is:
A) Hypothesis → Observation → Experiment → Conclusion
B) Observation → Hypothesis → Experiment → Conclusion
C) Experiment → Hypothesis → Observation → Conclusion
D) Conclusion → Observation → Hypothesis → Experiment
Answer: B) Observation → Hypothesis → Experiment → Conclusion
Scientists first observe phenomena, form testable hypotheses, design and conduct
experiments, then draw conclusions based on the results.
Question 3:
What is homeostasis?
A) The ability to move
B) The maintenance of stable internal conditions
C) The process of reproduction
D) The response to external stimuli
Answer: B) The maintenance of stable internal conditions
Homeostasis is the process by which living organisms maintain relatively stable
internal conditions despite changes in their external environment.
2. Chemistry of Life - Atoms and Molecules
Question 4:
The most abundant element in living organisms by mass is:
A) Carbon
B) Nitrogen
C) Oxygen
, D) Hydrogen
Answer: C) Oxygen
Oxygen makes up about 65% of human body mass, largely due to its presence in
water (H₂O), which comprises 60-70% of body weight.
Question 5:
Covalent bonds are formed when atoms:
A) Transfer electrons
B) Share electrons
C) Attract opposite charges
D) Repel each other
Answer: B) Share electrons
Covalent bonds form when two or more atoms share one or more pairs of electrons to
achieve stable electron configurations.
Question 6:
The pH scale measures:
A) Temperature
B) Concentration of hydrogen ions (H⁺)
C) Molecular weight
D) Electrical conductivity
Answer: B) Concentration of hydrogen ions (H⁺)
pH is the negative logarithm of hydrogen ion concentration. Lower pH means higher
H⁺ concentration (more acidic), higher pH means lower H⁺ concentration (more
basic).
3. Water and Its Properties
Question 7:
Water's unique properties are primarily due to:
A) Its large molecular size
B) Hydrogen bonding between molecules
C) Its high molecular weight
D) Being composed of three atoms
Answer: B) Hydrogen bonding between molecules
Water's polarity allows hydrogen bonds to form between molecules, giving water its
unique properties like high boiling point, surface tension, and cohesion.
Question 8:
Which property of water makes it an excellent solvent for ionic compounds?
A) Its nonpolar nature
B) Its polar nature
C) Its low density as ice
D) Its high heat capacity