Practice Exam 2026/2027 | Full- Questions with Answers &
Explanations | pdf
Overview
This WGU C190 Introduction to Biology Objective Assessment (OA) Practice Exam is a
comprehensive, exam-focused study resource designed to help students confidently prepare for
their final assessment. Built to mirror the competency-based format used at WGU, this
practice test emphasizes both foundational knowledge and real-world application of biological
concepts.
The exam includes 100 multiple-choice questions (A–D format) with clear, detailed
explanations for every answer. Questions are structured in a moderate-to-long format to reflect
actual OA difficulty, ensuring you are not just memorizing facts but truly understanding key
biological principles.
This Exam Covers
Cell structure and function (prokaryotic vs. eukaryotic)
DNA, RNA, and protein synthesis
Cellular respiration and photosynthesis
Enzymes and metabolism
Genetics and inheritance patterns
Evolution and natural selection
Human body systems and homeostasis
Ecology, ecosystems, and energy flow
Scientific reasoning and biological processes
1. Which organelle is responsible for producing ATP in eukaryotic cells?
A. Nucleus
B. Ribosome
,C. Mitochondrion
D. Golgi apparatus
✔️ Answer: C
Explanation: The mitochondrion generates ATP through cellular respiration.
2. What is the main function of DNA in a cell?
A. Energy production
B. Protein storage
C. Genetic information storage
D. Waste removal
✔️ Answer: C
Explanation: DNA stores hereditary information used for protein synthesis.
3. Which molecule carries amino acids during protein synthesis?
A. mRNA
B. tRNA
C. rRNA
D. DNA
✔️ Answer: B
Explanation: tRNA delivers amino acids to the ribosome.
4. What process converts glucose into ATP?
A. Photosynthesis
B. Cellular respiration
C. Fermentation
D. Diffusion
✔️ Answer: B
Explanation: Cellular respiration produces ATP from glucose.
,5. Which structure controls what enters and exits the cell?
A. Cell wall
B. Nucleus
C. Cell membrane
D. Cytoplasm
✔️ Answer: C
Explanation: The membrane regulates transport in and out of the cell.
6. Which macromolecule is primarily responsible for enzymes?
A. Lipids
B. Proteins
C. Carbohydrates
D. Nucleic acids
✔️ Answer: B
Explanation: Enzymes are proteins that catalyze reactions.
7. What is the basic unit of life?
A. Atom
B. Molecule
C. Cell
D. Tissue
✔️ Answer: C
Explanation: Cells are the smallest units capable of life.
8. What is the function of ribosomes?
, A. DNA replication
B. Protein synthesis
C. Lipid production
D. Energy storage
✔️ Answer: B
Explanation: Ribosomes assemble proteins.
9. Which process moves molecules from high to low concentration without energy?
A. Active transport
B. Diffusion
C. Endocytosis
D. Exocytosis
✔️ Answer: B
Explanation: Diffusion is passive transport.
10. Which organelle modifies and packages proteins?
A. Lysosome
B. Golgi apparatus
C. Nucleus
D. Vacuole
✔️ Answer: B
Explanation: Golgi processes and ships proteins.
11. What type of bond holds water molecules together?
A. Ionic
B. Covalent
C. Hydrogen
D. Metallic