ATI TEAS Science

Correct Answer: C

Rationale: Nociceptors detect pain. They are specialized nerve endings that respond to potentially harmful stimuli. When activated, nociceptors send signals to the brain, resulting in the sensation of pain. Deep pressure (A) and vibration (B) are detected by other types of receptors, while temperature (D) is detected by thermoreceptors. Therefore, the correct answer is C because nociceptors specifically respond to pain stimuli.

Correct Answer: B

Rationale: The correct answer is B: Secondary structure. Secondary structure is defined by the local folds and coils in the protein's polypeptide backbone, such as alpha helices and beta sheets. This level of structure does not involve interactions between different regions of the protein (tertiary) or multiple protein subunits (quaternary). Primary structure (A) refers to the linear sequence of amino acids. Tertiary structure (C) involves the 3D arrangement of secondary structures and other elements in a single polypeptide chain. Quaternary structure (D) pertains to the arrangement of multiple polypeptide subunits in a protein complex.

Correct Answer: A

Rationale: The correct answer is A because in a primary immune response, the first event is the recognition and phagocytosis of pathogens by macrophages. This is crucial for initiating the immune response by presenting antigens to T cells. Neutrophils (choice B) are important in later stages as part of the innate immune response. B lymphocytes (choice C) produce antibodies later in the response. Helper T cells (choice D) are activated by the antigens presented by macrophages and play a role in coordinating the immune response but are not the first event.

Correct Answer: D

Rationale: The correct answer is D: Catabolism. 1. Catabolism specifically refers to the process of breaking down large molecules into smaller molecules to release energy. 2. Metabolism (A) is the overall set of chemical reactions that occur in an organism, including anabolism and catabolism. 3. Bioenergetics (B) is the study of energy transformation in living organisms, not specifically the breakdown of molecules. 4. Anabolism (C) is the opposite process of catabolism, involving the building of large molecules from smaller ones, requiring energy input.

Correct Answer: A

Rationale: The correct answer is A: A control. A control in an experiment is used as a standard for comparison because it remains unchanged and is not subjected to the experimental treatment. By comparing the results of the experimental group to the control group, researchers can determine the effectiveness of the treatment. Variables (B) and constants (C) are factors that are manipulated or kept consistent, respectively, in an experiment but do not serve as a standard for comparison. Collected data (D) is the outcome of the experiment and is not used as a standard for comparison.