ati teas 7 science

Correct Answer: D

Rationale: The correct answer is D: Solar energy to electrical energy. Solar cells, also known as photovoltaic cells, convert sunlight (solar energy) directly into electricity through the photovoltaic effect. When sunlight hits the solar cell, photons from the sunlight are absorbed by the semiconducting material in the cell, creating an electric current. This process allows solar cells to generate electricity without moving parts or the need for any other energy sources. Explanation for other choices: A: Electrical energy to light energy - This is incorrect as solar cells do not convert electrical energy into light energy, but rather convert solar energy into electrical energy. B: Chemical energy to electrical energy - This is incorrect as solar cells do not involve any chemical reactions to produce electricity. C: Solar energy to thermal energy - This is incorrect as solar cells are designed to convert solar energy directly into electrical energy, not thermal energy.

Correct Answer: A

Rationale: The correct answer is A because polygenic inheritance refers to a trait that is influenced by multiple genes working together to produce a single phenotype. In contrast, pleiotropy occurs when a single gene has multiple effects on different traits. This distinction is crucial as it highlights the difference in the genetic basis of these phenomena. The other choices are incorrect because they either misinterpret the definitions of polygenic inheritance and pleiotropy (B and C) or provide vague statements without accurately distinguishing between the two concepts (D). The key to selecting the correct answer lies in understanding the fundamental genetic mechanisms underlying polygenic inheritance and pleiotropy.

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: B

Rationale: When a sound wave travels from air to water, its speed decreases because sound travels faster in denser mediums. Water is denser than air, so the speed of sound decreases. This decrease occurs due to the change in the medium's properties affecting the wave propagation speed. The other choices are incorrect because the speed of sound is not dependent on frequency (choice D) and it doesn't remain the same (choice C) when transitioning between different mediums. Choice A is incorrect as an increase in density leads to a decrease in speed, not an increase.

Correct Answer: C

Rationale: The correct answer is C: Phagocytes. Phagocytes are white blood cells responsible for the initial attack on pathogens by engulfing and digesting them. They include neutrophils, monocytes, and macrophages. Red blood cells (A) are not involved in the immune response. Platelets (B) are responsible for blood clotting, not attacking pathogens. Lymphocytes (D) play a role in specific immune responses but are not the primary cells responsible for the initial attack on pathogens.