ATI TEAS 7 science review

Correct Answer: C

Rationale: The correct answer is C: Skeletal muscle. Skeletal muscle is attached to bones and allows for voluntary movement, such as walking, running, and lifting objects. Smooth muscle, found in the walls of internal organs and blood vessels, is responsible for involuntary movements. Cardiac muscle is specific to the heart and controls involuntary contraction. Connective tissue, on the other hand, provides support and connects different structures in the body, but it is not responsible for voluntary movement like skeletal muscle.

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: C

Rationale: The correct answer is the pancreas. The hormone responsible for regulating blood sugar levels is insulin, which is produced by the pancreas. The pituitary gland produces various hormones that regulate other endocrine glands, the thyroid gland produces hormones that regulate metabolism, and the adrenal glands produce hormones involved in the stress response. Therefore, choices A, B, and D are incorrect in the context of regulating blood sugar levels.

Correct Answer: D

Rationale: The color of the reaction mixture is not a factor affecting the rate of a chemical reaction. Factors such as the concentration of reactants, temperature, and the presence of a catalyst can influence the rate of a chemical reaction by affecting the frequency of collisions between reactant molecules and the energy of those collisions. The color of the reaction mixture is a physical property and does not directly impact the kinetics or speed of the reaction process. It is a qualitative observation that does not alter the reaction rate or mechanisms involved.

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.