TEAS 7 practice test science

Correct Answer: B

Rationale: Tissues are groups of cells that work together to perform a specific function. They have similar structures that enable them to carry out their specialized functions effectively. Therefore, tissues are defined by both their function and structure, making option B the correct choice. Choices A, C, and D are incorrect because tissues are not solely defined by their appearance, location, or age, but rather by the shared function and structure of the cells within them.

Correct Answer: B

Rationale: Sublimation is the process by which a solid directly transforms into a gas without passing through the liquid phase. This occurs when the atmospheric pressure is lower than the vapor pressure of the solid, causing it to transition to a gas state. Choice A, evaporation, is the process where a liquid changes into a gas, not a solid. Choice C, condensation, is the opposite process where gas changes into a liquid. Choice D, melting, is the process where a solid changes into a liquid, not a gas.

Correct Answer: B

Rationale: The correct answer is B: To increase lung compliance. Surfactant is a substance produced by type II alveolar cells in the lungs that reduces surface tension in the alveoli. This reduction in surface tension helps to increase lung compliance, making it easier for the lungs to expand and contract during breathing. Improved lung compliance is essential for efficient gas exchange in the respiratory system, facilitating oxygen uptake and carbon dioxide removal. Choices A, C, and D are incorrect because surfactant does not trap dust particles, produce mucus, or generate oxygen during respiration. Instead, its primary function lies in reducing surface tension to prevent alveolar collapse and improve lung compliance for optimal gas exchange.

Correct Answer: A

Rationale: Molality (m) is the unit used to express concentration as a mass of solute per unit volume of solution. It is calculated by dividing the mass of solute in grams by the mass of the solvent in kilograms. Molality is preferred over molarity when there are large temperature variations as it is temperature-independent, making it a more accurate measure of concentration. Molarity (B) is the unit used to express concentration as moles of solute per liter of solution, weight percent (C) is the mass of solute per 100 parts of the total mass of the solution, and parts per million (D) is used to express very small concentrations where 1 ppm is equivalent to 1 mg of solute per liter of solution.

Correct Answer: B

Rationale: As the pH increases, the concentration of hydrogen ions decreases. The relationship is inversely proportional