ATI TEAS Science Test

Correct Answer: D

Rationale: Enzymes are protein molecules that serve as catalysts for certain biological reactions. Enzymes are biological molecules that speed up chemical reactions in living organisms by lowering the activation energy required for the reactions to occur. They are typically proteins that have specific shapes and active sites that allow them to interact with specific substrates and facilitate reactions without being consumed themselves. The other choices are incorrect because enzymes are not irrelevant, acidic, or lipid molecules; they are primarily proteins known for their catalytic properties.

Correct Answer: C

Rationale: For an experiment to be considered successful, it is essential that the data collected and results obtained can be reproduced or replicated by others. This reproducibility ensures the reliability and validity of the experiment's findings. It allows for independent verification of the results and contributes to the overall scientific rigor of the study. While having a reasonable hypothesis, a well-written lab report, and computer-aided statistical analysis are important aspects of an experiment, the ability to reproduce the data is crucial for establishing the experiment's credibility and success. Without reproducibility, the findings may not be reliable, and the experiment's outcomes cannot be verified independently, leading to doubts about its validity.

Correct Answer: B

Rationale: Formulating a hypothesis before conducting an experiment is crucial because it helps guide the investigation by suggesting what the investigator should be looking for. A hypothesis serves as a prediction or an educated guess about what might happen in the experiment, providing a clear direction for the research process. It allows the investigator to focus on specific variables and outcomes, making the experiment more organized and effective. Choice A is incorrect because the primary purpose of a hypothesis is not to boost an investigator's reputation but to guide the research. Choice C is incorrect as formulating a hypothesis is not primarily about impressing funders but about setting a clear direction for the study. Choice D is incorrect because the hypothesis is not meant to dictate which results to keep based on preconceived notions but to guide the investigation and allow for unbiased interpretation of results.

Correct Answer: B

Rationale: The correct answer is B. The process of coagulation, also known as blood clotting, begins instantly after a blood vessel has been damaged. When a blood vessel is injured, the body quickly responds by initiating a cascade of reactions to form a blood clot, which helps to stop bleeding and promote healing. Choices A, C, and D are incorrect because coagulation does not occur just when blood changes from a gel to liquid form, it is not a response of blood drying upon contact with air, and it is not simply the formation of fibrin. The primary trigger for coagulation is vascular injury.

Correct Answer: B

Rationale: Hemoglobin is a protein found in red blood cells that plays a crucial role in transporting oxygen from the lungs to the tissues and organs in the body. It is composed of four protein subunits, each containing a heme group that binds to oxygen molecules. Choice A is incorrect as hemoglobin is not an enzyme, but rather a protein. Choice C is incorrect as hemoglobin is not a lipid, but a protein. Choice D is incorrect as hemoglobin is not an acid, but a protein.