TEAS Science Practice Questions: Cells, Genetics, and Scientific Reasoning
The ATI TEAS science section covers several scientific concepts, including human anatomy and physiology, biology, chemistry, and scientific reasoning. Knowing facts is important, but you should also be able to interpret information, recognize variables, and apply scientific principles. This article focuses on cell biology, genetics, and scientific reasoning. The questions are original Naxles practice material, not official ATI questions.
Practice questions
1. Which organelle is most directly responsible for producing proteins?
- A. Ribosome
- B. Lysosome
- C. Vacuole
- D. Centriole
- Answer: A. Ribosome. Ribosomes translate messenger RNA into polypeptides.
2. Which structure regulates the movement of substances into and out of a cell?
- A. Cell membrane
- B. Nucleolus
- C. Chromosome
- D. Ribosome
- Answer: A. The cell membrane is selectively permeable.
3. Which molecule carries hereditary information?
- A. DNA
- B. Glucose
- C. Water
- D. Sodium chloride
- Answer: A. DNA. DNA contains genetic instructions.
4. What is the purpose of mitosis?
- A. To produce genetically similar cells for growth and repair
- B. To reduce the chromosome number by half
- C. To digest proteins
- D. To create oxygen from water in animals
- Answer: A. Mitosis supports growth and tissue repair by producing daughter cells with the same chromosome number.
5. Which process normally creates genetic variation by producing gametes?
- A. Meiosis
- B. Mitosis
- C. Diffusion
- D. Filtration
- Answer: A. Meiosis. Meiosis includes processes such as crossing over and independent assortment that contribute to genetic variation.
6. Which of the following is a hypothesis?
- A. A testable proposed explanation
- B. A statement that can never be tested
- C. A list of unrelated observations
- D. A conclusion guaranteed to be true
- Answer: A. A scientific hypothesis proposes an explanation that can be tested.
7. A researcher tests whether different amounts of sunlight affect plant growth. What is the independent variable?
- A. Amount of sunlight
- B. Plant height measured at the end
- C. Number of leaves produced
- D. Final mass of the soil
- Answer: A. The independent variable is what the researcher deliberately changes.
8. In the same experiment, what could be a dependent variable?
- A. Plant height after two weeks
- B. The amount of sunlight assigned
- C. The researcher's name
- D. The label on each pot
- Answer: A. Plant height is an outcome measured to determine whether sunlight affects growth.
9. Why should a scientific experiment control relevant conditions?
- A. To reduce the influence of other variables on the results
- B. To guarantee that the hypothesis is correct
- C. To prevent measurements
- D. To eliminate the need for repeated trials
- Answer: A. Controlling conditions helps researchers interpret the effect of the variable being tested.
10. Which statement best describes a scientific theory?
- A. A well-supported explanatory framework based on extensive evidence
- B. A random guess with no evidence
- C. A statement that cannot change in response to evidence
- D. A personal preference
- Answer: A. Scientific theories explain observations and are supported by accumulated evidence.
11. What is the basic unit of life?
- A. Cell
- B. Organ
- C. Organ system
- D. Molecule
- Answer: A. Cell. Cells are the smallest units generally considered living.
12. Which process moves particles from an area of higher concentration to an area of lower concentration without directly requiring cellular energy?
- A. Diffusion
- B. Active transport
- C. Protein synthesis
- D. Cell division
- Answer: A. Diffusion. Particles move down their concentration gradient through random motion.
13. What is an allele?
- A. A version of a gene
- B. A type of cell membrane
- C. A complete organ
- D. A chemical reaction
- Answer: A. Different alleles are alternative forms of a gene.
14. In a simple model, what is the genotype of an organism with two identical alleles for a gene?
- A. Homozygous
- B. Heterozygous
- C. Hybrid in every case
- D. Unrelated
- Answer: A. Homozygous. A homozygous genotype contains two identical alleles at the gene location.
15. Which organelle contains digestive enzymes that break down certain materials inside cells?
- A. Lysosome
- B. Ribosome
- C. Nucleus
- D. Chloroplast in animal cells
- Answer: A. Lysosome. Lysosomes contain enzymes that digest cellular waste and other materials.
16. What is the main role of an enzyme?
- A. Catalyze a chemical reaction
- B. Permanently increase the amount of product in every reaction
- C. Replace DNA
- D. Store all genetic information
- Answer: A. Enzymes speed up reactions by lowering activation energy.
17. Which observation best supports the conclusion that a substance is acidic in a standard aqueous pH model?
- A. It has a pH below 7 at approximately 25°C.
- B. It has a pH of exactly 7.
- C. It has a pH above 7.
- D. It contains no molecules.
- Answer: A. A pH below 7 indicates an acidic solution under these conditions.
18. Why is a control group useful in an experiment?
- A. It provides a comparison for evaluating the treatment or condition being tested.
- B. It guarantees the desired result.
- C. It replaces all measurements.
- D. It prevents the researcher from analyzing data.
- Answer: A. A suitable control helps distinguish the effect of the treatment from other influences.
19. What is the role of chlorophyll in photosynthesis?
- A. Absorb light energy
- B. Carry oxygen in human blood
- C. Digest proteins
- D. Filter water in the kidney
- Answer: A. Chlorophyll pigments absorb light used to drive photosynthetic processes.
20. Which statement describes an observation rather than an inference?
- A. The liquid changed from clear to blue.
- B. The reaction occurred because the student was careless.
- C. The substance must be dangerous.
- D. The experiment will certainly fail next time.
- Answer: A. It reports a directly observable change without proposing its cause.
