ATI TEAS 7 Science

Correct Answer: C

Rationale: The correct answer is C: RBC (Red Blood Cell). RBCs are biconcave discs that are round and flat without a nucleus. This unique shape allows for efficient gas exchange and flexibility to pass through narrow capillaries. Rationale: 1. Plasma (Choice A) is the liquid component of blood that carries various substances but does not have a specific shape or structure like RBCs. 2. Platelets (Choice B) are cell fragments involved in blood clotting and do not have the described characteristics of a biconcave disc without a nucleus. 3. WBCs (Choice D) are white blood cells responsible for immune responses and have a nucleus, unlike RBCs. In summary, RBCs are the only blood constituent among the choices that fits the description provided in the question.

Correct Answer: C

Rationale: The correct answer is C: Vitamin D. When the skin is exposed to sunlight, a form of cholesterol in the skin is converted into Vitamin D. This vitamin plays a crucial role in calcium absorption and bone health. Vitamin A is not synthesized in the skin but obtained through diet. Vitamin C is obtained from fruits and vegetables. Vitamin E is a fat-soluble vitamin found in nuts and seeds. In summary, only Vitamin D is synthesized in the skin upon sunlight exposure, making it the correct answer.

Correct Answer: B

Rationale: The correct answer is B: Cytoplasm. Cytoplasm is the fluid-filled, jelly-like substance within the cell that suspends the organelles. It is where many cellular processes occur. The nucleus (A) contains genetic material, not the organelles. The plasma membrane (C) is the cell's outer boundary, not the internal fluid. The Golgi apparatus (D) is an organelle involved in processing and packaging proteins, not the cell's fluid. Therefore, the correct answer is cytoplasm.

Correct Answer: D

Rationale: The correct answer is D because all the options are valid obstacles to achieving controlled nuclear fusion on Earth. Lack of suitable materials (A) is crucial due to extreme conditions, limited fusion fuels (B) can hinder sustained reactions, and containing plasma (C) is challenging to prevent energy loss. Therefore, all factors must be addressed for successful fusion energy production.

Correct Answer: D

Rationale: In osmosis, solvent moves from an area of low solute concentration to high solute concentration to equalize concentration. This is due to the principle of diffusion where molecules move from high to low concentration. Choice D is correct as it aligns with this principle. Choice A is incorrect because osmosis involves solvent movement, not solute movement. Choices B and C are incorrect as temperature does not determine the direction of solvent movement in osmosis.