ATI TEAS 7 science review

Correct Answer: B

Rationale: The periosteum, the tough outer layer of bone, serves the purpose of providing protection to the bone and nourishing it through the blood vessels it contains. It acts as a protective layer for the bone structures. Choices A, C, and D are incorrect because the periosteum does not produce red blood cells (which is the function of bone marrow), form joint surfaces (which is typically the role of articular cartilage), or store minerals (which is primarily done by bone tissue itself and not the periosteum).

Correct Answer: C

Rationale: RNA interference (RNAi) is a biological process that involves the silencing of gene expression by inhibiting the translation of mRNA or by degrading mRNA molecules. This mechanism plays a crucial role in regulating gene expression and can be used to selectively silence specific genes. By interfering with the expression of specific genes, RNAi can downregulate protein production from those genes. Therefore, option C, 'Inhibits the expression of specific genes,' is the correct role of RNA interference in silencing genes. Options A, B, and D are incorrect because RNA interference does not increase protein production, promote gene mutation, or repair damaged DNA; its primary function is to inhibit gene expression by degrading or interfering with mRNA.

Correct Answer: B

Rationale: Fusion is the process by which lighter nuclei combine to form heavier nuclei, releasing a large amount of energy in the process. This process is the source of energy in stars, including our Sun. Fission, the process of splitting heavier nuclei into lighter nuclei, is not correct. Radioactivity involves the emission of particles or radiation from the nucleus of an unstable atom, which is different from fusion. A chain reaction is a self-sustaining reaction where the products of one reaction cause further reactions, which is unrelated to fusion.

Correct Answer: D

Rationale: Concentric contraction refers to the condition where a muscle shortens in length while generating force, leading to movement at a joint. This type of contraction is commonly associated with the lifting phase of an exercise where the muscle is actively shortening against resistance. Isometric contraction (Choice A) involves muscle contraction without a change in muscle length, Eccentric contraction (Choice B) involves the muscle lengthening while generating force, and Isotonic contraction (Choice C) refers to muscle contraction against a constant load with a change in muscle length.

Correct Answer: A

Rationale: The Pauli exclusion principle states that no two electrons in an atom can have the same set of quantum numbers. This principle defines the maximum number of electrons allowed in each energy level, influencing the structure of the atom. Choice B is incorrect as it refers to the concept of electrostatic attraction, not directly related to the Pauli exclusion principle. Choice C is incorrect as it pertains to the wave-particle duality, a different aspect of quantum mechanics. Choice D is incorrect as it relates to the arrangement of protons and neutrons in the nucleus, not governed by the Pauli exclusion principle.