ati teas 7 science

Correct Answer: C

Rationale: Step 1: Amphiprotic substances can donate and accept protons, making them capable of acting as both acids and bases. Step 2: When amphiprotic substances react, they can donate or accept protons depending on the reaction conditions. Step 3: This ability allows them to exhibit properties of both acids and bases. Step 4: Therefore, Choice C is correct as it accurately describes the nature of amphiprotic substances. Summary: A: Incorrect - Amphiprotic substances can react with both acids and bases, not just acids. B: Incorrect - Amphiprotic substances can react with both acids and bases, not just bases. D: Incorrect - Amphiprotic substances are not inert; they actively participate in chemical reactions by donating and accepting protons.

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: To secrete digestive enzymes. The pancreas secretes enzymes such as amylase, lipase, and proteases that help break down carbohydrates, fats, and proteins in the small intestine. This aids in the digestion and absorption of nutrients. Storing bile (A) is the role of the gallbladder, digesting proteins (C) is primarily done by the stomach and small intestine, and absorbing nutrients (D) mainly occurs in the small intestine.

Correct Answer: B

Rationale: The adrenal glands are responsible for secreting adrenaline and cortisol in response to stress, triggering the fight-or-flight response. Adrenaline increases heart rate and blood flow, while cortisol releases energy stores. The pancreas regulates blood sugar, the thyroid gland controls metabolism, and the pituitary gland regulates hormone production but are not directly involved in the fight-or-flight response.

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.