CLEP Natural Sciences Exam

The CLEP: Natural Sciences examination was developed by the College Board as a way for individuals to demonstrate undergraduate-level knowledge and skills in this subject. Almost three thousand American colleges give credit to students who pass a CLEP exam; for this reason, many college-bound students take a CLEP exam in order to skip over introductory courses.

To succeed on the Natural Sciences exam, students will need to master the following topics and skills: the fundamental facts, concepts, and principles of natural science; interpretation and comprehension of information in the form of graphs, diagrams, tables, equations, and verbal passages; and the qualitative and quantitative application of scientific principles. The content of the exam is broken down as follows: the origin and evolution of life and the classification of organisms (10% of the exam); cell organization, cell division, the chemical nature of the gene, bioenergetics, and biosynthesis (10%); the structure, function, and development of organisms (20%); concepts of population biology with emphasis on ecology (10%); atomic and nuclear structure, elementary particles, and nuclear reactions (7%); chemical elements, compounds and reactions, molecular structure, and molecular bonding (10%); heat, thermodynamics, states of matter, classical mechanics, and relativity (12%); electricity and magnetism, waves, and light and sound (4%); galaxies, stars, and the solar system (7%); and the Earth’s atmosphere, hydrosphere, structure, properties, surface features, geological processes, and history (10%). The Natural Sciences exam consists of 120 multiple-choice questions and must be completed within 90 minutes.


After the exam is complete, an unofficial score report will be made available. This score report will include the total score on a scale of 20 to 80; the American Council on Education recommends that students get credit if they score 50 or above. The total score is the raw score (number of correct answers) adjusted according to the difficulty of the exam version. The College Board does not distinguish between unanswered questions and questions answered incorrectly, so test-takers are encouraged to respond to every question. Some of the questions on the exam are pre-test questions, which are used to develop future versions of the exam and do not contribute to the raw score. It is impossible for test-takers to determine which questions are pre-test questions. The CLEP exams are administered in both computer and paper formats at over a thousand locations throughout the world. To register for an exam, visit the College Board website.

CLEP Natural Sciences Practice Questions

1. During which part of aerobic respiration is the most ATP per molecule of glucose produced?
A: alcohol fermentation
B: chemosmosis
C: lactic acid cycle
D: glycolysis
E: citric acid fermentation

2. How are ions formed?
A: protons are either gained or lost.
B: protons are shared
C: electrons are shared
D: electrons are either gained or lost
E: neutrons are either gained or lost

3. Which kind of bond keeps the secondary structure of a protein intact?
A: hydrogen bond
B: ionic bond
C: peptide bond
D: covalent bond
E: oxygen bond

4. Which of the following waves of visible light has the highest frequency?
A: indigo
B: green
C: violet
D: yellow
E: blue

5. What kind of biological compound prevents materials from moving across the cell membrane?
A: carbohydrates
B: ribosomes
C: nucleic acids
D: internal proteins
E: lipid

6. A train is moving at 50 km/h, at which point the engineer applies the brake. If it takes the train 35 m to stop completely, what was the magnitude of the train’s acceleration as the engineer brakes?
A: 5 m/s2
B: 12 m/s2
C: 1.7 m/s2
D: 17.4 m/s2
E: 2.8 m/s2

7. What is the name of the molecule that moves information from the nucleus to the cytoplasm?
A: DNA
B: lipid
C: hydrogen
D: mRNA
E: tRNA

8. If a 40 kilogram cube is hung from a beam by two vertical ropes, how much tension is in each rope?
A: 10 N
B: 50 N
C: 100 N
D: 150 N
E: 200 N

9. If a five kilogram ball is dropped from a height of one meter, about how long will it take to reach the ground?
A: 0.2 second
B: 0.5 second
C: 1 second
D: 2 seconds
E: 4 seconds

10. According to the theory of evolution, which of the following types of cell is considered the most primitive?
A: yeast
B: prokaryotic
C: gamete
D: eukaryotic
E: autotrophic

CLEP Natural Sciences Answer Key

1. B. Chemosmosis occurs through a semipermeable membrane.
2. D. Ions are charged atoms.
3. A. A hydrogen bond is one in which a hydrogen atom is attracted to an electronegative atom, often nitrogen.
4. C. Red is the form of visible light with the lowest frequency.
5. E. Lipids are insoluble in water but soluble in nonpolar organic solvents.
6. E. The equation for acceleration is 40 in which v is velocity and t is time.
7. D. mRNA is the form of RNA that helps transfer genetic information from the cell nucleus to the ribosomes in the cytoplasm.
8. C. The tension will be evenly distributed between the two ropes.
9. C. The mass of the ball is inconsequential; the acceleration of matter due to gravity is 9.8 m2.
10. B. Neither the nucleus nor the organelles of a prokaryote are bound by a membrane.

CLEP Natural Sciences Test Breakdown