Nursing Elites

1. The formula for calculating heart rate is HR = (220 - age) * 0.65. If a patient's heart rate is 136.5, what is their age?

• A. 30
• B. 40
• C. 50
• D. 60

Correct answer: B

Rationale: Rearrange the formula to solve for age: age = 220 - (HR / 0.65). Substitute the heart rate (136.5) to get 40 years old.

2. What is the name of a condition where the immune system mistakenly attacks healthy body tissues?

• A. Allergy
• B. Autoimmune disease
• C. Immunodeficiency
• D. Sepsis

Correct answer: B

Rationale: The correct answer is B: Autoimmune disease. This condition occurs when the immune system mistakenly targets and attacks healthy tissues in the body, leading to inflammation and tissue damage. Autoimmune diseases can affect various organs and systems in the body, such as rheumatoid arthritis, lupus, and multiple sclerosis. Allergies (A) involve the immune system overreacting to harmless substances, but they do not involve attacking healthy tissues. Immunodeficiency (C) refers to a weakened immune system that is less able to fight off infections. Sepsis (D) is a life-threatening condition caused by the body's response to an infection, not an autoimmune reaction.

3. A lab test result shows a blood glucose level of 5.5 millimoles per liter (mmol/L). What is the equivalent level in milligrams per deciliter (mg/dL)?

• A. 55 mg/dL
• B. 5.5 mg/dL
• C. 0.55 mg/dL
• D. 550 mg/dL

Correct answer: A

Rationale: This requires a double conversion: millimoles to milligrams and liters to deciliters. 1 millimole is equal to 180.15 milligrams, and 1 liter is equal to 10 deciliters. Multiply the glucose level (5.5 mmol/L) by the conversion factor for millimoles to milligrams (180.15 mg/mmol) and then divide by the conversion factor for liters to deciliters (10 dL/L): 5.5 mmol/L * 180.15 mg/mmol / 10 dL/L ≈ 55 mg/dL.

4. Which process involves the body's natural defense against inhaled dust and allergens?

• A. Cellular respiration
• B. Gas exchange
• C. Ciliary action
• D. Bronchoconstriction

Correct answer: C

Rationale: The correct answer is C: Ciliary action. Cilia are tiny hair-like structures lining the respiratory tract that help trap and remove inhaled dust and allergens. When these particles are trapped in the mucus produced by the cilia, the cilia beat in a coordinated fashion to move the mucus and its trapped particles out of the respiratory system, preventing them from reaching the lungs. Cellular respiration (A) is the process by which cells generate energy from nutrients, not a defense mechanism. Gas exchange (B) refers to the exchange of oxygen and carbon dioxide in the lungs, not a defense mechanism. Bronchoconstriction (D) is the narrowing of the airways, often in response to triggers like allergens, but it is not the body's natural defense mechanism against inhaled dust and allergens.

5. A salt solution that conducts electricity well is most likely

• A. A saturated solution
• B. A concentrated solution of a strong electrolyte
• C. A dilute solution of a weak acid
• D. A mixture of a neutral compound and water

Correct answer: B

Rationale: The correct answer is B: "A concentrated solution of a strong electrolyte." Strong electrolytes completely dissociate into ions in solution, thereby increasing the conductivity of the solution. Concentrated solutions have a higher amount of dissolved solute particles, which leads to more ions available for conducting electricity. In contrast, saturated solutions may contain undissolved solute, limiting the number of ions in solution. Dilute solutions have fewer ions and weak acids only partially dissociate, reducing conductivity. A neutral compound and water do not provide ions for conducting electricity. Therefore, a concentrated solution of a strong electrolyte is most likely to conduct electricity well due to the high concentration of ions present.

6. What property of a substance refers to its ability to undergo a chemical change and form new substances with different properties?

• A. Density
• B. Mass
• C. Reactivity
• D. Volume

Correct answer: c

Rationale: Reactivity refers to a substance's ability to undergo a chemical change or reaction, forming new substances with different properties.

Similar Questions