ATI TEAS 7 Science

Correct Answer: A

Rationale: The correct answer is A: Group 1. Alkali metals are located in Group 1 of the periodic table because they have one electron in their outermost shell, making them highly reactive. These elements include lithium, sodium, potassium, and others. Group 2 (Choice B) consists of alkaline earth metals, Group 7 (Choice C) consists of halogens, and Group 8 (Choice D) consists of noble gases. Alkali metals exhibit unique properties due to their single valence electron, distinguishing them from elements in the other groups mentioned.

Correct Answer: B

Rationale: The correct answer is B: Liver. The liver is responsible for detoxifying chemicals and metabolizing drugs due to its enzymes that break down substances. It also helps in excreting waste products. The kidneys (A) filter blood and regulate fluid balance. The heart (C) pumps blood throughout the body. The pancreas (D) produces digestive enzymes and insulin. Thus, the liver is the primary organ involved in detoxification and drug metabolism.

Correct Answer: B

Rationale: When the force acting on an object is doubled, according to Newton's second law (F=ma), the acceleration of the object will also double. This is because acceleration is directly proportional to force when mass is constant. Therefore, the correct answer is B. Explanation for other choices: A: Acceleration is halved - Incorrect, doubling the force will increase acceleration, not decrease it. C: Acceleration remains unchanged - Incorrect, acceleration changes in direct proportion to force. D: Acceleration quadruples - Incorrect, acceleration only doubles when the force is doubled, not quadruples.

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.

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.