ATI TEAS 7 Science

Correct Answer: B

Rationale: The correct answer is B: The ability to maintain a stable internal environment. Homeostasis is the body's ability to regulate and maintain a stable internal environment despite external changes. This includes maintaining stable levels of temperature, pH, and nutrients. Choice A is incorrect because homeostasis is not solely about body temperature. Choice C is incorrect as it does not encompass the overall concept of homeostasis. Choice D is incorrect because although regulating blood glucose levels is part of homeostasis, it does not fully capture the broad scope of maintaining a stable internal environment.

Correct Answer: C

Rationale: The correct answer is C: Polypeptide. Translation is the process in which mRNA is decoded by ribosomes to synthesize a specific polypeptide. During translation, transfer RNA (tRNA) molecules bring specific amino acids to the ribosome based on the mRNA codons, and these amino acids are joined together to form a polypeptide chain. The other choices are incorrect because translation does not result in the production of DNA (A), lipids (B), or carbohydrates (D). Translation specifically involves the synthesis of polypeptides, making choice C the correct answer.

Correct Answer: C

Rationale: The correct answer is C because lifting a box to place it on a shelf involves exerting a force to overcome gravity, resulting in the displacement of the box. Work is defined as the product of force and displacement in the direction of the force applied. In this scenario, the force applied (lifting the box) results in the box being displaced vertically, which meets the criteria for work being done. Choices A, B, and D do not represent work being done on an object because in these situations, the objects do not experience a displacement in the direction of the force applied. In choice A, the wall does not move, so no displacement occurs. In choice B, carrying a heavy object without lifting it does not involve any vertical displacement. In choice D, holding a book stationary in your hand does not result in any displacement of the book. Therefore, only choice C fulfills the criteria for work being done on an object.

Correct Answer: B

Rationale: The correct answer is B: In a covalent bond, the shared electrons spend more time closer to the more electronegative atom. This is because the more electronegative atom attracts the electrons more strongly, causing them to be closer to that atom. This creates a partial negative charge on the more electronegative atom and a partial positive charge on the other atom. This distribution of electron density contributes to the stability of the covalent bond. Choices A, C, and D are incorrect because: A: Are completely transferred to one atom - This describes an ionic bond, not a covalent bond. C: Remain equidistant between the two atoms - Shared electrons in a covalent bond are not equidistant but are closer to one atom. D: Do not influence the bond strength - The distribution of shared electrons significantly influences the strength and properties of a covalent bond.

Correct Answer: C

Rationale: The correct answer is C: Carries specific amino acids to the ribosomes. tRNA is responsible for carrying specific amino acids to the ribosomes during protein synthesis. It recognizes the codons on mRNA and pairs them with the corresponding amino acids. This process ensures that the correct amino acids are added to the growing polypeptide chain. Choice A is incorrect because tRNA does not transcribe DNA into mRNA; that is the role of RNA polymerase. Choice B is incorrect because decoding the genetic code on mRNA is done by tRNA along with the ribosomes. Choice D is incorrect because tRNA does not modify the structure of proteins; that is typically done by enzymes or post-translational modifications.