Nursing Elites

1. Which statement about white blood cells is true?

• A. B cells are responsible for antibody production.
• B. White blood cells are produced in the bone marrow before entering the bloodstream.
• C. Platelets, a specialized class of blood cells, function to clot blood and stop bleeding.
• D. The majority of white blood cells are active throughout life, providing immunity across all age groups.

Correct answer: A

Rationale: The correct answer is A: B cells, a type of white blood cell, are responsible for producing antibodies in response to pathogens. Antibodies play a crucial role in identifying and neutralizing foreign substances like bacteria and viruses in the body, aiding in the immune response and protecting against infections. This function is essential for maintaining a healthy immune system. White blood cells, including B cells, are produced in the bone marrow before entering the bloodstream. Platelets, not white blood cells, are a specialized class of blood cells that function to clot blood and stop bleeding. While white blood cells provide immunity, not all of them are active throughout life as some have specific lifespans and functions.

2. What term describes a series of muscle contractions that transports food down the digestive tract in a wave-like fashion?

• A. digestion
• B. deglutition
• C. defecation
• D. peristalsis

Correct answer: D

Rationale: Peristalsis is the correct term for the series of muscle contractions that move food down the digestive tract in a wave-like manner. This process helps propel food through the esophagus, stomach, and intestines, facilitating digestion and nutrient absorption. Digestion (Choice A) refers to the breakdown of food into smaller components, deglutition (Choice B) is the act of swallowing, and defecation (Choice C) is the elimination of waste from the body. Therefore, peristalsis is the most appropriate term to describe the described muscle contractions in the digestive system.

3. Which of the following correctly describes mitosis?

• A. Mitosis occurs in germ cells.
• B. Mitosis occurs in somatic cells.
• C. Mitosis involves the reduction of chromosome number by half.
• D. Mitosis produces four genetically different cells.

Correct answer: B

Rationale: The correct answer is B. Mitosis occurs in somatic cells where a single cell divides to produce two identical daughter cells. Germ cells undergo meiosis, not mitosis. Choice C is incorrect as mitosis results in the preservation of the same chromosome number in daughter cells. Choice D is inaccurate as mitosis produces genetically identical cells, not genetically different ones.

4. Which of the following is an example of a flat bone?

• A. Femur
• B. Scapula
• C. Humerus
• D. Tibia

Correct answer: B

Rationale: The correct answer is B, the Scapula. Flat bones, such as the scapula, are thin, flattened bones that provide protection to internal organs and serve as attachment points for muscles. The other choices, femur, humerus, and tibia, are examples of long bones, which are characterized by their elongated structure and are primarily involved in supporting weight and facilitating movement.

5. Which valve prevents the backflow of blood into the left ventricle as it leaves through the aorta?

• A. Pulmonary semilunar valve
• B. Aortic semilunar valve
• C. Tricuspid valve
• D. Mitral valve

Correct answer: B

Rationale: The aortic semilunar valve is the correct answer as it prevents the backflow of blood into the left ventricle once it has been pumped into the aorta. The pulmonary semilunar valve prevents backflow into the right ventricle, the tricuspid valve controls blood flow between the right atrium and ventricle, and the mitral valve regulates blood flow between the left atrium and ventricle. Therefore, option B is the correct choice for this question.

Similar Questions