100+ Free STAAR Biology Practice Questions
Pass your State of Texas Assessments of Academic Readiness (STAAR) End-of-Course Biology exam on the first try — instant access, no signup required.
A change in the nucleotide sequence of a gene is called a
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Key Facts: STAAR Biology Exam
5
reporting categories: cells, genetics, evolution and classification, processes, and ecology
TEA STAAR Biology Blueprint
33-35
questions on the STAAR Biology EOC, worth 40 points
TEA STAAR Biology Blueprint, Spring 2026
40
total points available on the STAAR Biology assessment
TEA STAAR Biology Blueprint
4
performance levels: Did Not Meet, Approaches, Meets, and Masters Grade Level
TEA STAAR Performance Standards
Spring 2026
administration that fully implements the new Biology science TEKS
TEA Science Assessment Updates
3-4 hours
recommended scheduled STAAR test-session length, with a 7-hour maximum
TEA District and Campus Coordinator Resources
$8.06
TEA 2025-26 private-school cost per student for Biology
TEA 2025-2026 Private Schools Test Administration Information
Approaches
Grade Level is the minimum level reported as passing on STAAR Biology
TEA STAAR Performance Standards
STAAR Biology is a Texas end-of-course exam covering cells, genetics, evolution and classification, biological processes, and ecology. The Spring 2026 blueprint lists about 33-35 questions worth 40 points across five reporting categories, using the newly implemented Biology TEKS. STAAR is delivered primarily online with multiple-choice, technology-enhanced, short constructed-response, and cluster items. Students generally finish in about three hours, but TEA allows same-day completion up to seven hours. Passing is reported as Approaches Grade Level or higher. This free bank gives 100 original multiple-choice practice questions with full explanations.
Sample STAAR Biology Practice Questions
Try these sample questions to test your STAAR Biology exam readiness. Each question includes a detailed explanation. Start the interactive quiz above for the full 100+ question experience with AI tutoring.
1Which cell structure is the site of protein synthesis?
2Which organelle contains chlorophyll and carries out photosynthesis in a plant cell?
3Which of the following is a feature that distinguishes a eukaryotic cell from a prokaryotic cell?
4The four major classes of biomolecules are carbohydrates, lipids, proteins, and nucleic acids. Which class serves as the primary short-term source of energy for cells?
5Which biomolecule contains the monomers called amino acids?
6An enzyme speeds up a chemical reaction in a cell by
7A student tests how temperature affects an enzyme's activity. Activity rises as temperature increases to 37 degrees Celsius, then drops sharply at 60 degrees Celsius. What best explains the drop?
8Which equation best summarizes photosynthesis?
9During cellular respiration, the energy released from glucose is used mainly to produce molecules of
10Photosynthesis and cellular respiration are related because the products of one process are the
About the STAAR Biology Exam
STAAR Biology is the Texas high school end-of-course assessment that measures how well students apply the Biology Texas Essential Knowledge and Skills (TEKS). The new science TEKS are fully implemented in the Spring 2026 administration. The exam is organized around five reporting categories: Cell Structure and Function; Mechanisms of Genetics; Biological Evolution and Classification; Biological Processes and Systems; and Interdependence within Environmental Systems. STAAR is administered primarily online and includes multiple-choice, technology-enhanced, short constructed-response, and cluster question formats. Students must perform at Approaches Grade Level or higher to pass.
Assessment
The STAAR Biology end-of-course assessment is built around five reporting categories: Cell Structure and Function; Mechanisms of Genetics; Biological Evolution and Classification; Biological Processes and Systems; and Interdependence within Environmental Systems. The 2026 blueprint lists about 33-35 questions worth 40 points. Forms include multiple-choice and technology-enhanced items, short constructed response items, and cluster question sets that share a stimulus.
Time Limit
Scheduled for 3-4 hours; students may continue until the end of the same school day, with no more than 7 hours of testing time.
Passing Score
Approaches Grade Level or higher; performance levels are Did Not Meet, Approaches, Meets, and Masters Grade Level.
Exam Fee
No direct student fee for Texas public school administrations; TEA's 2025-26 private-school cost schedule lists $8.06 per student for Biology. (Texas Education Agency (TEA))
STAAR Biology Exam Content Outline
Cell Structure and Function
Prokaryotic and eukaryotic cells, organelles such as ribosomes, mitochondria, and chloroplasts, the cell membrane and transport including osmosis and active transport, homeostasis, the four biomolecules, the cell cycle and mitosis, cell differentiation, cancer, and viruses.
Mechanisms of Genetics
DNA structure, base pairing, and semiconservative replication; transcription and translation; the central dogma; codons; mutations; meiosis and crossing-over; Mendelian crosses and Punnett squares; non-Mendelian inheritance such as codominance and incomplete dominance; sex-linked traits; and biotechnology.
Biological Evolution and Classification
Fossil, anatomical, embryological, and molecular evidence for common ancestry; homologous and analogous structures; natural and artificial selection; adaptation; speciation; genetic drift and gene flow; taxonomy and binomial nomenclature; domains and kingdoms; cladograms; and dichotomous keys.
Biological Processes and Systems
Photosynthesis and cellular respiration and how they cycle matter and transfer energy; ATP and enzymes; aerobic and anaerobic respiration; levels of biological organization; plant systems such as stomata; human body systems; and feedback mechanisms that maintain homeostasis.
Interdependence within Environmental Systems
Producers, consumers, and decomposers; food chains, food webs, and energy pyramids; the roughly ten percent rule of energy transfer; symbiosis, competition, and predation; carbon and nitrogen cycles; ecological succession; biodiversity and ecosystem stability; limiting factors; carrying capacity; and human impact.
How to Pass the STAAR Biology Exam
What You Need to Know
- Passing score: Approaches Grade Level or higher; performance levels are Did Not Meet, Approaches, Meets, and Masters Grade Level.
- Assessment: The STAAR Biology end-of-course assessment is built around five reporting categories: Cell Structure and Function; Mechanisms of Genetics; Biological Evolution and Classification; Biological Processes and Systems; and Interdependence within Environmental Systems. The 2026 blueprint lists about 33-35 questions worth 40 points. Forms include multiple-choice and technology-enhanced items, short constructed response items, and cluster question sets that share a stimulus.
- Time limit: Scheduled for 3-4 hours; students may continue until the end of the same school day, with no more than 7 hours of testing time.
- Exam fee: No direct student fee for Texas public school administrations; TEA's 2025-26 private-school cost schedule lists $8.06 per student for Biology.
Keys to Passing
- Complete 500+ practice questions
- Score 80%+ consistently before scheduling
- Focus on highest-weighted sections
- Use our AI tutor for tough concepts
STAAR Biology Study Tips from Top Performers
Frequently Asked Questions
What is the STAAR Biology EOC?
The STAAR Biology end-of-course assessment is the Texas high school exam that measures whether students have mastered the Biology TEKS. Most Texas students take it after completing their Biology course, and it is one of the EOC assessments required for graduation.
What topics are on STAAR Biology?
The exam is organized into five reporting categories: Cell Structure and Function; Mechanisms of Genetics; Biological Evolution and Classification; Biological Processes and Systems; and Interdependence within Environmental Systems. Together these cover cells, biomolecules, DNA and genetics, evolution, photosynthesis and respiration, body systems, and ecology.
How many questions are on STAAR Biology?
The 2026 Biology blueprint lists approximately 33-35 questions worth 40 points. Forms include multiple-choice and technology-enhanced items, short constructed-response items, and cluster question sets that share a stimulus.
How is STAAR Biology scored?
TEA reports performance in four levels: Did Not Meet Grade Level, Approaches Grade Level, Meets Grade Level, and Masters Grade Level. Students who achieve Approaches Grade Level or higher have passed the exam.
Is STAAR Biology online, and are calculators allowed?
STAAR Biology is administered primarily online, with paper available only in limited circumstances such as accommodations. A calculator is permitted, and the online platform provides an appropriate calculator tool along with a periodic table reference.
How much time do students have for STAAR Biology?
Districts schedule STAAR sessions for three to four hours because students are expected to finish in about three hours. Students who need more time may continue until the end of the same school day, but may not spend more than seven hours working on the assessment.