ati teas 7 science

Correct Answer: C

Rationale: The correct answer is C: Isotonic solution. An isotonic solution has the same concentration of solute as another solution, leading to no net movement of water across a semipermeable membrane. This term is commonly used in biology and medicine to describe solutions with equal osmotic pressure. Incorrect answers: A: Saturated solution - A saturated solution is one in which the maximum amount of solute has been dissolved at a given temperature. B: Unsaturated solution - An unsaturated solution has a lower concentration of solute compared to what it could dissolve at a given temperature. D: Concentrated solution - A concentrated solution simply means a solution with a high amount of solute dissolved in a solvent, but it does not necessarily mean it has the same concentration as another solution.

Correct Answer: C

Rationale: Renin is the correct answer. Renin is an enzyme released by the kidneys in response to low blood pressure. It plays a key role in regulating blood pressure by initiating a series of reactions that ultimately lead to the constriction of blood vessels and retention of water and sodium. This helps to raise blood pressure back to normal levels. Insulin (choice A) is involved in regulating blood sugar levels, not blood pressure. Testosterone (choice B) and Estrogen (choice D) are sex hormones that do not have a direct impact on kidney function and blood pressure regulation.

Correct Answer: B

Rationale: The correct answer is B: Refraction. Refraction occurs when light bends as it passes through different mediums of varying densities, such as hot air above a desert surface. This bending of light causes the mirage effect where distant objects appear distorted or displaced. Diffraction (A) is the bending of light around obstacles, not relevant in this context. Interference (C) involves the interaction of light waves, not applicable to mirages. Polarization (D) is the orientation of light waves, unrelated to the mirage effect in deserts.

Correct Answer: B

Rationale: Insulin is the correct answer as it is responsible for lowering blood sugar levels by promoting the uptake of glucose into cells. Glucagon raises blood sugar levels, adrenaline and cortisol are stress hormones that increase blood sugar levels. Therefore, the correct choice is B.

Correct Answer: B

Rationale: The correct answer is B. A decomposition reaction involves a single compound breaking down into two or more simpler substances. In choice B, CaCO3 decomposes into CaO and CO2. This reaction follows the general form AB → A + B, making it a clear example of a decomposition reaction. Choices A, C, and D involve synthesis or combination reactions, where simpler substances combine to form a more complex compound, making them incorrect for this question.