TEAS 7 practice test science

Correct Answer: B

Rationale: The correct answer is B because strong acids release more hydrogen ions compared to weak acids. This higher concentration of ions in the solution leads to a higher electrical conductivity. Strong acids ionize completely in solution, producing a higher concentration of ions that can conduct electricity, whereas weak acids only partially ionize, resulting in a lower concentration of ions and lower electrical conductivity. Choice A is incorrect because the concentration of the acid does not directly determine its electrical conductivity. Choice C is incorrect as the ability to dissolve salts is not directly related to electrical conductivity. Choice D is incorrect because the pH of the solution, although related to acidity, does not directly determine the electrical conductivity.

Correct Answer: A

Rationale: - Adaptive radiation is a process where a single ancestral species diversifies into multiple descendant species to exploit different ecological niches within a heterogeneous environment. - This diversification occurs due to the different selective pressures present in various habitats, leading to the evolution of distinct traits and adaptations in different descendant species. - Option A accurately describes the process of adaptive radiation, where the initial species undergoes rapid speciation to occupy different ecological roles and adapt to diverse environmental conditions. - Options B, C, and D do not accurately describe adaptive radiation but refer to other evolutionary processes such as convergent evolution, natural selection, and gaps in the fossil record, respectively.

Correct Answer: A

Rationale: The correct answer is A: Produces hormones that regulate growth and metabolism. The pituitary gland is often referred to as the 'master gland' because it produces and releases hormones that regulate various bodily functions, including growth, metabolism, reproduction, and stress response. It does not filter blood or remove waste products (option B), store and release bile (option C), or produce red blood cells (option D). The pituitary gland's primary role is in hormone production and regulation, influencing many essential functions in the body.

Correct Answer: C

Rationale: Lymph nodes are essential for filtering lymph and trapping harmful substances. They are a vital part of the immune system as they remove pathogens and harmful substances from the lymph before it returns to the bloodstream. Lymph nodes do not store blood or produce antibodies, making choice C the correct answer. Choice A is incorrect because lymph nodes do not store blood; they primarily filter lymph. Choice B is incorrect as lymph nodes do not produce antibodies; that function is mainly carried out by specialized cells within the immune system. Choice D is incorrect as lymph nodes do not perform all the functions listed, making it an incorrect answer.

Correct Answer: B

Rationale: When a car brakes to a stop, friction between the tires and the road acts as an unbalanced force causing deceleration. This friction force opposes the motion of the car, resulting in a decrease in speed until the car comes to a complete stop. Choice A is incorrect because if the forces were balanced, the car would not experience any deceleration. Choice C is incorrect because if the force were unbalanced in the direction of motion, the car would continue to move instead of coming to a stop. Choice D is incorrect because friction between the tires and the road does exert a force, causing deceleration.