Nursing Elites

1. Which of the following best describes a blood clot stimulating further clotting?

• A. a positive feedback mechanism.
• B. a negative feedback mechanism.
• C. a process turning itself off.
• D. nervous system communication

Correct answer: A

Rationale: A blood clot stimulating further clotting is an example of a positive feedback mechanism. In positive feedback, the response enhances or amplifies the original stimulus, leading to an increase in the activity. In this case, the formation of a blood clot triggers more clotting activity, creating a cycle of increasing clot formation. Negative feedback mechanisms, on the other hand, work to maintain homeostasis by counteracting changes. Choices B, C, and D are incorrect as they do not accurately describe the situation of a blood clot stimulating further clotting.

2. Blood cells are produced in the organs of the _______ system.

• A. endocrine
• B. skeletal
• C. superior to
• D. inferior to

Correct answer: C

Rationale: Blood cells are produced in the organs of the hematopoietic system. The correct answer is 'superior to' as this refers to the location of the organs responsible for blood cell production, typically bone marrow found in bones such as the vertebrae, ribs, and skull. 'Endocrine' (Choice A) refers to a different system responsible for hormone production. 'Skeletal' (Choice B) relates to bones but not specifically to the production of blood cells. Choices C and D, 'superior to' and 'inferior to,' do not make sense in the context of blood cell production and are incorrect.

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

• A. pulmonic
• B. mitral
• C. tricuspid
• D. aortic

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.

4. Paired organs, such as the kidneys or lungs, are said to be

• A. bisexual.
• B. bilingual.
• C. bilateral.
• D. bivalent.

Correct answer: C

Rationale: The correct answer is C: 'bilateral.' Paired organs like the kidneys or lungs are described as bilateral because they occur in pairs on both sides of the body. Option A 'bisexual' refers to having both male and female reproductive organs, which is not the correct term for paired organs. Option B 'bilingual' refers to being able to speak two languages, which is not related to the description of paired organs. Option D 'bivalent' means having two valences, which is also unrelated to the context of paired organs.

5. Positive feedback mechanisms usually result in

• A. changes returning values away from a set point.
• B. stable conditions around a set point.
• C. unstable conditions.
• D. long-term changes.

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.

Similar Questions