ATI Anatomy and Physiology Online Practice

Correct Answer: A

Rationale: The correct answer is A: Body temperature, blood pressure, and pulse rate. Vital signs are measurements that indicate the body's basic functions and are essential indicators of health. Body temperature, blood pressure, and pulse rate are classic vital signs routinely checked in medical settings to assess a person's overall health status. Choices B, C, and D are not considered vital signs. The appearance of the skin, red blood cell count, and oxygen level may provide valuable health information but are not classified as vital signs. Similarly, body weight, age, and gender are important factors in healthcare but are not vital signs. Visual acuity and auditory sharpness relate to sensory functions and are not typically categorized as vital signs.

Correct Answer: C

Rationale: The correct answer is C. Homeostatic mechanisms aim to maintain internal stability within the body. Choices A, B, and D all represent examples of homeostatic mechanisms. Shivering helps generate heat to raise body temperature back to normal levels. Increasing heart rate and force of contraction work to restore blood pressure. Insulin secretion after a meal helps regulate blood sugar levels. On the other hand, retaining fluid excessively can lead to fluid imbalance rather than maintaining internal stability, making it the incorrect choice.

Correct Answer: C

Rationale: Positive feedback mechanisms usually result in unstable conditions. In a positive feedback loop, the output enhances or amplifies the changes that are occurring, leading to a deviation from the initial set point. Therefore, positive feedback does not bring values back towards the set point (Choice A). Choice B is incorrect because positive feedback does not promote stability around a set point. Choice D is also incorrect as positive feedback mechanisms typically do not lead to long-term changes; instead, they intensify the initial change, causing instability.

Correct Answer: D

Rationale: The correct answer is 'never having smoked.' Research suggests that one of the common characteristics among centenarians is that they have never smoked. Smoking is a well-known risk factor for various diseases and can significantly reduce lifespan. Choice A, 'a high level of exercise throughout life,' is not a universal characteristic among centenarians, although exercise can contribute to a healthy lifestyle. Choice B, 'long-lived relatives,' while genetics can play a role in longevity, not all centenarians have long-lived relatives. Choice C, 'following the Mediterranean diet,' is a healthy dietary choice but not a defining characteristic shared by all centenarians.

Correct Answer: C

Rationale: The correct answer is C. Living organisms use oxygen to release energy stored in the molecules of food through a process called cellular respiration. This process involves breaking down glucose molecules in the presence of oxygen to produce energy in the form of ATP. Choice A is incorrect because oxygen does not directly reduce heat production in organisms. Choice B is incorrect because oxygen is involved in accepting electrons rather than donating them in cellular metabolism. Choice D is incorrect because the removal of metabolic wastes is not the primary role of oxygen in living organisms.