Nursing Elites

1. Which of the following statements regarding the working of the heart is not correct?

• A. The atria contract, and the valves open to allow blood into the ventricles.
• B. The heartbeat begins when the heart muscles relax, and blood flows into the atria.
• C. The valves close to stop blood from flowing backward.
• D. The ventricles contract, forcing blood to leave the heart.

Correct answer: B

Rationale: The correct answer is B because the heartbeat actually begins when the heart muscles relax, allowing the chambers to fill with blood. The contraction phase follows, which propels blood out of the heart. The other statements are accurate in describing the normal sequence of events in the heart's functioning: the atria contract to push blood into the ventricles, the valves close to prevent backflow of blood, and the ventricles contract to pump blood out of the heart.

2. When light interacts with a perfectly smooth surface, like a mirror, the dominant interaction is:

• A. Refraction
• B. Diffraction
• C. Total internal reflection
• D. Specular reflection

Correct answer: D

Rationale: When light interacts with a perfectly smooth surface like a mirror, the dominant interaction is specular reflection. Specular reflection occurs when light rays are reflected off a smooth surface at the same angle as the incident angle, resulting in a clear and sharp reflection. Refraction, which involves the bending of light as it passes from one medium to another, is not the dominant interaction with a perfectly smooth surface. Diffraction, the bending of light waves around obstacles, is not the dominant interaction with smooth surfaces. Total internal reflection occurs when light is reflected back into a medium due to encountering a boundary at an angle greater than the critical angle, but it is not the dominant interaction on a perfectly smooth surface like a mirror.

3. What is the common name for the compound CH₃COOH?

• A. Acetic acid
• B. Formic acid
• C. Butyric acid
• D. Propionic acid

Correct answer: A

Rationale: The compound CH₃COOH is commonly known as acetic acid. Acetic acid is a clear, colorless liquid with a sour taste and a pungent smell. It is a weak acid found in vinegar and is used in the production of various chemicals. Formic acid, butyric acid, and propionic acid are different organic acids with distinct chemical structures and properties, but they are not the common name for the compound CH₃COOH.

4. What is the largest lymphatic vessel in the body?

• A. Jugular vein
• B. Thoracic duct
• C. Subclavian vein
• D. Aorta

Correct answer: B

Rationale: The thoracic duct is the largest lymphatic vessel in the body, responsible for draining lymph from most parts of the body except for the right upper quadrant. The jugular vein, subclavian vein, and aorta are not part of the lymphatic system; they are blood vessels and do not serve as lymphatic vessels. Therefore, choices A, C, and D are incorrect as they are not associated with the lymphatic system's transport of lymph.

5. The resolution of an optical instrument, like a microscope, refers to its ability to distinguish between:

• A. Different colors of light
• B. The presence or absence of light
• C. Variations in intensity
• D. Very close, nearly identical objects

Correct answer: D

Rationale: The resolution of an optical instrument, such as a microscope, refers to its ability to distinguish between very close, nearly identical objects. This is crucial in microscopy to clearly visualize and differentiate fine details and structures. Resolving power plays a significant role in determining the quality and effectiveness of an optical instrument. Choices A, B, and C are incorrect because the resolution of an optical instrument does not primarily deal with different colors of light, presence or absence of light, or variations in intensity. Instead, it specifically focuses on the instrument's ability to differentiate between objects that are very close and nearly identical in nature.

Similar Questions