positive feedback mechanisms
Logo

Nursing Elites

ATI RN

ATI Anatomy and Physiology Online Practice

1. What do positive feedback mechanisms do?

Correct answer: B

Rationale: Positive feedback mechanisms amplify or increase changes in a system, moving conditions away from the normal state. This makes choice B the correct answer. Choice A is incorrect as positive feedback does not cause long-term changes but rather accelerates deviations from the norm. Choice C is incorrect because positive feedback does not bring conditions back to normal; instead, it amplifies deviations. Choice D is incorrect as positive feedback does not usually lead to stable conditions but rather to further deviations from the normal state.

2. Which of the following cardiac valves prevents blood from returning to the left ventricle of the heart?

Correct answer: D

Rationale: The correct answer is the aortic valve. The aortic valve is located between the left ventricle and the aorta, preventing the backflow of blood into the left ventricle once it has been pumped out during systole. Choice A, pulmonic, is incorrect as it is associated with the right side of the heart. Choice B, mitral, is incorrect as it is the valve between the left atrium and ventricle. Choice C, tricuspid, is incorrect as it is located between the right atrium and ventricle.

3. A parietal layer of a serous membrane lines cavities, whereas a visceral layer of a serous membrane covers organs.

Correct answer: B

Rationale: In serous membranes, the parietal layer lines the cavities, providing support and protection, while the visceral layer covers the organs, reducing friction and allowing them to move freely. Therefore, the correct answer is 'lines cavities; covers organs.' Choices C and D are incorrect because serous membranes do not secrete mucus; instead, they secrete a watery serous fluid. Choice A is incorrect as it reverses the functions of the parietal and visceral layers in relation to organs and cavities.

4. What function is associated with the dermal layer of the skin?

Correct answer: B

Rationale: The correct function associated with the dermal layer of the skin is to provide support and structure to the skin. The dermis is the thickest layer of the skin and is responsible for maintaining the skin's integrity and firmness. Choices A, C, and D are incorrect as sensory perception, protection from UV rays, and insulation are functions associated with other layers of the skin, such as the epidermis and subcutaneous tissue.

5. Homeostasis exists if concentrations of water, nutrients, and oxygen in the body and heat and pressure __________.

Correct answer: B

Rationale: Homeostasis is the body's ability to maintain stable internal conditions despite external changes. To achieve this balance, concentrations of essential substances must remain within specific ranges. Choice A is incorrect because decreasing concentrations would not maintain stability. Choice C is incorrect as increasing concentrations when the body is stressed would disrupt homeostasis. Choice D is incorrect as fluctuating greatly between high and low values would also not support the body's stability. Therefore, the correct answer is B, as it aligns with the concept of homeostasis by emphasizing the need for stability within certain limits.

Similar Questions

Which of the following best describes a blood clot stimulating further clotting?
Living organisms use oxygen to __________________.
The ability of an organism to sense and react to changes in its body illustrates
Which part of the nephron is closest to the collecting duct?
Most of the terminology to name and describe body parts and their functions comes from

Access More Features

ATI RN Basic
$69.99/ 30 days

  • 5,000 Questions with answers
  • All ATI courses Coverage
  • 30 days access

ATI RN Premium
$149.99/ 90 days

  • 5,000 Questions with answers
  • All ATI courses Coverage
  • 30 days access

Other Courses