🧬 DAT Biology Practice Exam – 20 Questions

Instructions: Choose the best answer. Aim to complete the exam in 25 minutes to simulate test pacing.

1. Which organelle is responsible for synthesizing proteins?

A. Lysosome
B. Ribosome
C. Nucleus
D. Mitochondrion

2. What is the correct sequence of the stages in mitosis?

A. Prophase → Metaphase → Anaphase → Telophase
B. Metaphase → Prophase → Telophase → Anaphase
C. Telophase → Anaphase → Metaphase → Prophase
D. Prophase → Anaphase → Metaphase → Telophase

3. Which molecule functions as the final electron acceptor in aerobic respiration?

A. NAD+
B. Glucose
C. Oxygen
D. Water

4. Which of the following is a correct base-pairing in DNA?

A. A–G
B. A–U
C. C–A
D. G–C

5. In Hardy-Weinberg equilibrium, if 9% of a population is homozygous recessive, what is the frequency of the dominant allele?

A. 0.3
B. 0.7
C. 0.49
D. 0.81

6. Which part of the brain controls coordination and balance?

A. Cerebrum
B. Medulla
C. Cerebellum
D. Thalamus

7. What is the main function of the large intestine?

A. Protein digestion
B. Water absorption
C. Lipid breakdown
D. Glucose reabsorption

8. Which hormone stimulates the release of eggs during ovulation?

A. FSH
B. LH
C. Progesterone
D. Estrogen

9. Which of the following is a feature of prokaryotic cells?

A. Membrane-bound organelles
B. Nucleus
C. Circular DNA
D. Mitochondria

10. Which of the following best describes mutualism?

A. One organism benefits, the other is harmed
B. Both organisms benefit
C. One benefits, the other is unaffected
D. Neither benefits

11. What is the primary function of tRNA?

A. To transcribe DNA into RNA
B. To carry amino acids to the ribosome
C. To replicate the DNA
D. To degrade mRNA after translation

12. The liver plays a major role in:

A. Blood oxygenation
B. Urea production
C. Insulin secretion
D. Water reabsorption

13. Which biome has permafrost and very short summers?

A. Temperate forest
B. Tropical rainforest
C. Taiga
D. Tundra

14. In which organ does the majority of nutrient absorption occur?

A. Stomach
B. Small intestine
C. Large intestine
D. Liver

15. Which process occurs in the chloroplasts of plant cells?

A. Cellular respiration
B. Protein synthesis
C. Photosynthesis
D. DNA replication

16. Which structure is responsible for transporting water in vascular plants?

A. Phloem
B. Stomata
C. Xylem
D. Chloroplasts

17. Which of the following is not part of the innate immune system?

A. Skin
B. Macrophages
C. Antibodies
D. Inflammation

18. Which process results in four non-identical haploid cells?

A. Mitosis
B. Binary fission
C. Meiosis
D. Budding

19. Which of the following is an example of a vestigial structure?

A. Wings of a bird
B. Human appendix
C. Gills in fish
D. Claws in a lion

20. What is the function of the sarcomere in muscle cells?

A. Oxygen transport
B. Action potential generation
C. Protein synthesis
D. Muscle contraction