Natural Sciences
1 free practice test · 120 questions · 1h 30min · No sign-up required
About This Exam
The CLEP Natural Sciences exam is a broad general-education science survey rather than a specialist science major exam. It covers roughly equal amounts of biological science and physical science, with some interdisciplinary and laboratory-style interpretation questions.
What's Covered
- Biological Science (50%) - evolution, classification, cell biology, genetics, bioenergetics, organism structure and function, heredity, and ecology
- Physical Science (50%) - atomic structure, chemistry, thermodynamics, mechanics, waves, light, sound, electricity, magnetism, astronomy, and Earth science
- Scientific reasoning - interpretation of graphs, tables, diagrams, and short laboratory or data-analysis scenarios
- Applications - qualitative and some quantitative use of scientific principles in familiar contexts
For the official exam description, see the College Board CLEP Natural Sciences page.
Study Tips
- This exam rewards breadth over obscure detail. Focus on core principles and what they mean in real examples.
- Be comfortable switching rapidly between biology and physical science. The official exam is broad and often changes domains from one question to the next.
- Review graphs, units, and proportional reasoning. Many science questions are really interpretation questions in disguise.
- Know the big cycles and big models: evolution, cell theory, energy flow, atomic structure, Newtonian mechanics, plate tectonics, and the water and carbon cycles.
- Practice vocabulary in context. Terms like isotope, trophic level, entropy, refraction, and carrying capacity should feel usable, not just familiar.
How to Register
Register at clep.collegeboard.org. The exam costs $97 and can be taken at a testing center or remotely. Check your college's CLEP policy before registering. Military service members, their spouses, and eligible veterans may be able to take CLEP exams at no cost through DANTES funding.
About Our Practice Tests
All questions are original and written to match the exam's general-education tone and broad science coverage. Practice Mode gives instant feedback with explanations. Test Mode simulates the timed exam and holds feedback until the end.
Sample Practice Questions
Review these sample questions to get a feel for the exam. For the full interactive experience, use the Practice Test above.
- A) individuals deliberately choose traits that improve survival
- B) heritable traits that improve survival and reproduction become more common over generations
- C) organisms improve their bodies during life and pass those changes to offspring
- D) the environment directly instructs DNA what to do
- E) species evolve toward a fixed goal of perfection
View Answer & Explanation
Correct Answer:
B) heritable traits that improve survival and reproduction become more common over generations
Explanation:
Natural selection acts on inherited variation. Traits that improve reproductive success tend to increase in frequency over time.
- A) absorbs energy and jumps to a higher level
- B) falls from a higher level to a lower level
- C) remains in the ground state indefinitely
- D) is ejected from the atom regardless of photon energy
- E) splits the nucleus into lighter fragments
View Answer & Explanation
Correct Answer:
B) falls from a higher level to a lower level
Explanation:
Dropping to a lower energy level releases the energy difference as a photon. Absorption is the opposite process.
- A) convergent evolution producing analogous structures
- B) reproductive isolation as a key step toward speciation
- C) stabilizing selection reducing variation
- D) genetic drift that always increases heterozygosity
- E) artificial selection by human breeders
View Answer & Explanation
Correct Answer:
B) reproductive isolation as a key step toward speciation
Explanation:
When gene flow stays blocked long enough, diverging populations can become reproductively isolated and begin functioning as separate species.
- A) number of protons only
- B) number of electrons in the neutral atom
- C) number of neutrons in the nucleus
- D) overall nuclear charge sign
- E) periodic table group
View Answer & Explanation
Correct Answer:
C) number of neutrons in the nucleus
Explanation:
Isotopes share the same number of protons but differ in neutron count, which changes mass number without changing elemental identity.
- A) the species' ecological niche
- B) a group of closely related species sharing many derived traits
- C) the age of the lineage in millions of years
- D) whether the organism is unicellular
- E) the dominant biome where it is found
View Answer & Explanation
Correct Answer:
B) a group of closely related species sharing many derived traits
Explanation:
In taxonomy, genus groups closely related species. Species is the more specific rank nested inside it.