Nursing Elites

1. What is the half-life of a radioactive isotope, and how does it relate to its decay rate?

• A. The time it takes for half of the initial sample to decay.
• B. The time it takes for all the sample to decay.
• C. The rate at which new isotopes are created.
• D. The energy released during decay.

Correct answer: A

Rationale: Half-life tells the time it takes for half of the original radioactive nuclei to decay, offering an indication of the decay rate.

2. What is the term for the pressure exerted by blood against the walls of blood vessels?

• A. Heart rate
• B. Blood pressure
• C. Cardiac output
• D. Stroke volume

Correct answer: B

Rationale: The correct answer is B: Blood pressure. Blood pressure is the term used to describe the force or pressure exerted by blood against the walls of blood vessels. It is typically measured in millimeters of mercury (mmHg) and consists of two main components - systolic pressure (the pressure when the heart is contracting) and diastolic pressure (the pressure when the heart is relaxed). Heart rate (A) refers to the number of times the heart beats per minute and is not specifically related to the pressure against blood vessel walls. Cardiac output (C) is the volume of blood pumped by the heart per minute, while stroke volume (D) is the volume of blood pumped by the heart in a single contraction. These are related to heart function but not specifically to the pressure against blood vessel walls.

3. The human immunodeficiency virus (HIV) targets and destroys which type of immune cell?

• A. Neutrophils
• B. Macrophages
• C. Helper T cells
• D. Memory B cells

Correct answer: A

Rationale: The correct answer is C: Helper T cells. HIV targets and destroys Helper T cells, which are a crucial component of the immune system responsible for coordinating the immune response. Neutrophils and macrophages are also important immune cells, but they are not the primary target of HIV. Memory B cells are responsible for mounting a rapid response upon re-exposure to a pathogen but are not the main target of HIV. Thus, HIV primarily affects Helper T cells, leading to the weakening of the immune system and the development of acquired immunodeficiency syndrome (AIDS).

4. What is the outermost protective layer of the kidney?

• A. Renal cortex
• B. Renal medulla
• C. Renal capsule
• D. Renal pelvis

Correct answer: C

Rationale: The correct answer is C, renal capsule. The renal capsule is a tough fibrous layer that surrounds the kidney and provides protection. It helps maintain the shape of the kidney and serves as a barrier against infections and injuries. The renal cortex (A) is the outer region of the kidney where filtration occurs. The renal medulla (B) is the inner region of the kidney where urine is formed and collected. The renal pelvis (D) is a funnel-shaped structure that collects urine from the kidney and funnels it into the ureter. Therefore, the renal capsule is specifically the outermost protective layer of the kidney.

5. What is the main topic of the passage?

• A. Benefits of bioremediation in cleaning oil spills.
• B. Dangers of microplastics to marine ecosystems.
• C. History of plastic production and its global impact.
• D. Comparison of different waste management strategies.

Correct answer: B

Rationale: The passage focuses on the specific issue of microplastics in the marine environment and their harmful effects.

6. Which of the following is the primary function of the lymphatic system?

• A. Transporting oxygen and nutrients to cells
• B. Carrying waste products away from tissues
• C. Regulating body temperature
• D. Producing red blood cells

Correct answer: B

Rationale: The correct answer is B: 'Carrying waste products away from tissues.' The primary function of the lymphatic system is to collect excess fluid from tissues and return it to the bloodstream, while also transporting waste products, pathogens, and cellular debris away from tissues to be filtered and eliminated. This helps maintain fluid balance in the body and supports the immune system by removing harmful substances. Options A, C, and D do not accurately describe the primary function of the lymphatic system, making them incorrect choices.

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