TEAS Science · 90 questions · Page 5 of 9

    90 Free TEAS Science Practice Questions with Answers

    90 original TEAS 7-style science practice questions, each with a full rationale, distractor analysis, and study tips. Use these to drill the exact concepts the ATI TEAS tests — then jump into a timed quiz when you're ready.

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    TEAS Science Questions, Answers, and Rationales

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    #41

    Scientific Reasoning and Bias

    An independent research firm is hired by a major sugar producer to conduct a study on the health effects of artificial sweeteners. Which of the following is the most significant concern regarding the validity of this study's conclusions?

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    Answer: B. Conflict of interest resulting in biased results

    A study funded by an entity with a financial stake in the outcome is primarily concerned with bias and conflicts of interest.

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    #42

    Respiratory System Gas Exchange

    During a physiological assessment, which of the following changes would result in a significant decrease in the diffusion of oxygen into the bloodstream?

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    Answer: A. An increase in the thickness of the alveolar-capillary membrane

    A thicker alveolar-capillary membrane creates a larger barrier, slowing the rate of oxygen diffusion into the blood.

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    #43

    Microbiology Classifications

    An environmental microbiologist is studying various extremophiles. They identify a specific organism as a psychrophile, meaning it thrives in extremely cold environments. Based on the classification of microorganisms by temperature, which of the following is the most likely optimal growth temperature for this psychrophile?

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    Answer: B. 12°C (53.6°F)

    Psychrophiles are cold-loving microorganisms with an optimal growth temperature typically between -5°C and 15°C.

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    #44

    Mendelian Genetics Concepts

    In a species of flowering plant, tall stems (T) are completely dominant over short stems (t). A researcher crosses a tall plant with a short plant, and the resulting offspring consist of 24 tall plants and 26 short plants. Which of the following represents the most likely genotypes of the parent plants?

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    Answer: C. Tt × tt

    A 1:1 trait ratio in offspring indicates a cross between a heterozygous parent (Tt) and a homozygous recessive parent (tt).

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    #45

    Scientific Reasoning and Data Interpretation

    A researcher is studying the effects of two new nutritional supplements, Compound X and Compound Y, on the lifespan of fruit flies (Drosophila melanogaster). After 20 days, the data shows the following survival rates: - **Control Group (Standard Diet):** 60% survival - **Compound X Group:** 65% survival - **Compound Y Group:** 25% survival Based on this data, which of the following is a valid conclusion?

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    Answer: C. Compound Y treatment resulted in the lowest survival rate among all tested groups.

    Learn how to interpret experimental data and compare treatment groups to controls with this TEAS science practice question and detailed explanation.

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    #46

    Cellular Biology and Specialization

    Which of the following processes best illustrates the concept of cellular differentiation?

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    Answer: C. An unspecialized hematopoietic cell developing into a specific red blood cell.

    Cellular differentiation is the process by which an unspecialized stem cell becomes a specialized cell with a specific function and structure.

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    #47

    Cellular Biology & Enzymes

    In a biological system, how do enzymes specifically influence the rate of a chemical reaction?

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    Answer: B. They function as biological catalysts that lower the activation energy required for a reaction.

    Enzymes are biological catalysts that speed up chemical reactions by lowering the activation energy without being consumed in the process.

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    #48

    Endocrine System Regulation

    Following a carbohydrate-rich meal, which specific cell type in the pancreas is stimulated to release a hormone that promotes the uptake of glucose by body cells?

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    Answer: B. Beta cells releasing insulin

    Beta cells in the pancreatic islets secrete insulin to lower blood glucose levels by promoting cellular uptake.

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    #49

    Respiratory System Function

    A patient is diagnosed with emphysema, a condition characterized by the destruction of the walls of the alveoli. Which of the following is the most direct consequence of this structural damage?

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    Answer: B. A decrease in the surface area available for gas exchange.

    Alveolar damage reduces the surface area available for gas exchange, leading to lower oxygen levels in the blood.

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    #50

    Scientific Method and Hypothesis

    A researcher is designing a study to investigate the effect of soil salinity on the germination of radish seeds. Which of the following statements represents a valid hypothesis for this study?

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    Answer: B. If the concentration of salt in the water increases, then the germination rate of the seeds will decrease.

    A hypothesis is a testable prediction. Option B correctly predicts a relationship between salt concentration and seed germination.

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    Study TEAS Science in depth

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