Nursing Elites

1. In a normally functioning cardiovascular system, where does the heartbeat originate?

• A. Atrioventricular nodes
• B. Bundle of His
• C. Purkinje fibers
• D. Sinoatrial node

Correct answer: D

Rationale: The correct answer is the Sinoatrial (SA) node. The SA node is known as the natural pacemaker of the heart as it initiates the electrical impulses responsible for the heartbeat. The other choices, such as the Atrioventricular (AV) nodes, Bundle of His, and Purkinje fibers, are involved in conducting the electrical signals generated by the SA node to coordinate the heart's contractions. Therefore, they do not serve as the primary origin of the heartbeat.

2. An obstetrician tells a 42-year-old patient that she can have a healthy baby, but that she is of 'advanced maternal age.' The patient is so upset that she fails to listen to the rest of the doctor's advice, goes home in a huff, and immediately dyes her hair.

• A. the age of the sperm.
• B. the age of her eggs.
• C. her risk of developing diabetes.
• D. her cholesterol level, not her appearance.

Correct answer: B

Rationale: The correct answer is 'the age of her eggs.' As women age, the quality of their eggs decreases, leading to a higher risk of chromosomal abnormalities and infertility. This decline in egg quality is why advanced maternal age is associated with a higher risk of certain pregnancy complications. Choices A, C, and D are incorrect because the primary concern in this context is related to the age-related changes in a woman's eggs, not sperm, diabetes risk, or cholesterol levels.

3. Organ systems consist of organs, which consist of tissues.

• A. True
• B. False
• C. Not Sure
• D. None of the above

Correct answer: A

Rationale: The statement is true. Organ systems are made up of organs, which in turn are composed of tissues. Organs are structures made up of two or more types of tissues that work together to perform specific functions. Tissues, on the other hand, are groups of cells that work together to perform a specific function. Therefore, organs are made up of tissues, and organ systems consist of organs.

4. 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.

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

• A. Sensory perception
• B. To provide support and structure to the skin
• C. Protection from UV rays
• D. Insulation

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.

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