Nursing Elites

1. Fluorescent microscopy utilizes which property of certain molecules to create a visible image?

• A. Staining properties
• B. Light absorption
• C. Fluorescence emission
• D. Refraction

Correct answer: C

Rationale: Fluorescent microscopy relies on the property of certain molecules to fluoresce when exposed to specific wavelengths of light. When these molecules absorb light energy, they become excited and then emit light at a longer wavelength, producing a visible image. This emitted light is what is used to create the image in fluorescent microscopy, making option C, fluorescence emission, the correct answer. Staining properties (option A) are used to enhance contrast in microscopy but are not the primary mechanism in fluorescent microscopy. Light absorption (option B) is involved in the excitation of fluorescent molecules but is not the property used to create the visible image. Refraction (option D) is the bending of light as it passes through different mediums and is not the property utilized in fluorescent microscopy.

2. Which of the following structures is unique to eukaryotic cells?

• A. Cell walls
• B. Nuclei
• C. Cell membranes
• D. Vacuoles

Correct answer: B

Rationale: Nuclei are structures that are unique to eukaryotic cells. Prokaryotic cells lack a defined nucleus, and their genetic material floats freely in the cytoplasm. Eukaryotic cells have nuclei that house the genetic material in the form of chromosomes, separated from the cytoplasm by a nuclear membrane. This distinct organelle is a key feature that sets eukaryotic cells apart from prokaryotic cells. Cell walls (Choice A) are found in plant cells, fungi, and some prokaryotes but are not unique to eukaryotic cells. Cell membranes (Choice C) are present in both prokaryotic and eukaryotic cells, serving as a barrier that encloses the cell contents. Vacuoles (Choice D) are membrane-bound organelles found in both plant and animal cells, making them not unique to eukaryotic cells.

3. During exercise, oxygen is used to convert glucose into energy for muscles. This process is called:

• A. Aerobic respiration
• B. Anaerobic respiration
• C. Glycolysis
• D. Lactic acid fermentation

Correct answer: A

Rationale: Aerobic respiration is the process by which cells use oxygen to convert glucose into energy. This process occurs in the mitochondria of cells and is the most efficient way to produce energy during exercise. Anaerobic respiration and glycolysis are alternative pathways for energy production when oxygen is limited, typically occurring during high-intensity exercise. Lactic acid fermentation, on the other hand, occurs in the absence of oxygen and leads to the production of lactic acid, causing muscle fatigue and soreness.

4. What is the term for the involuntary muscle contractions that move food through the digestive tract?

• A. Segmentation
• B. Peristalsis
• C. Chyme
• D. Emulsification

Correct answer: B

Rationale: Peristalsis is the correct term for the involuntary muscle contractions that move food through the digestive tract. These contractions help push food along the digestive system, facilitating digestion and absorption of nutrients. Segmentation, on the other hand, refers to the mixing and breaking down of food in the intestines, not the movement of food. Chyme is the semi-fluid mass of partially digested food in the stomach and small intestine, not the muscle contractions. Emulsification is the process of breaking down fat globules into smaller droplets to aid in digestion, not the movement of food through the digestive tract. Therefore, peristalsis is the most appropriate term for this function.

5. What is the function of the lymphatic system?

• A. To transport oxygen
• B. To filter waste from the blood
• C. To produce red blood cells
• D. To regulate body temperature

Correct answer: B

Rationale: The correct answer is B: 'To filter waste from the blood.' The lymphatic system is responsible for draining excess fluid from tissues, absorbing fats from the digestive system, and filtering out harmful substances and waste products from the blood. It also plays a crucial role in the body's immune defense by transporting white blood cells and antibodies to fight off infections. Choices A, C, and D are incorrect because transporting oxygen, producing red blood cells, and regulating body temperature are functions performed by other systems in the body, such as the respiratory system, bone marrow, and thermoregulatory mechanisms, respectively.

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