Nursing Elites

1. Which property of a wave represents the distance between two successive identical points on a wave?

• A. Wavelength
• B. Amplitude
• C. Frequency
• D. Period

Correct answer: a

Rationale: Wavelength is the distance between two identical points (like crests or troughs) on a wave.

2. Which type of glial cell provides structural support and insulation for neurons in the central nervous system?

• A. Schwann cells
• B. Astrocytes
• C. Oligodendrocytes
• D. Microglia

Correct answer: C

Rationale: The correct answer is C: Oligodendrocytes. Oligodendrocytes are a type of glial cell found in the central nervous system that provide structural support and insulation for neurons by forming myelin sheaths around axons. Schwann cells, on the other hand, are found in the peripheral nervous system. Astrocytes play a role in nutrient transfer and maintaining the blood-brain barrier. Microglia are responsible for immune defense and clearing debris in the CNS. Therefore, oligodendrocytes are specifically responsible for providing structural support and insulation for neurons in the central nervous system.

3. What is the shape of the DNA molecule?

• A. Linear
• B. Circular
• C. Double helix
• D. Straight chain

Correct answer: C

Rationale: Rationale: The shape of the DNA molecule is a double helix. This structure was first described by James Watson and Francis Crick in 1953. The double helix shape consists of two strands that are twisted around each other in a spiral. This shape allows DNA to be compactly stored within the cell nucleus and provides stability to the molecule. The other options (A) Linear, (B) Circular, and (D) Straight chain do not accurately describe the shape of the DNA molecule.

4. Testosterone is a crucial hormone in the male reproductive system. What is its primary function?

• A. Egg production
• B. Sperm production and development
• C. Regulation of the menstrual cycle
• D. Milk production

Correct answer: B

Rationale: The correct answer is B: Sperm production and development. Testosterone is a hormone primarily produced in the testes and is essential for the development of male reproductive tissues, including the testes and prostate. It plays a key role in the production of sperm cells (spermatogenesis) and the development of secondary sexual characteristics in males, such as facial hair and muscle mass. Testosterone is not involved in egg production (A), regulation of the menstrual cycle (C), or milk production (D) as these are functions associated with female reproductive hormones.

5. Positron emission tomography (PET) scans utilize a key property of positrons for medical imaging. What is this property?

• A. High mass
• B. Positive charge
• C. Extreme stability
• D. Identical behavior to electrons

Correct answer: B

Rationale: The correct answer is B: 'Positive charge.' Positron emission tomography (PET) scans rely on the fact that positrons are positively charged particles. When a positron is emitted during radioactive decay, it quickly collides with an electron, resulting in annihilation and the release of two gamma rays in opposite directions. These gamma rays are detected by the PET scanner to create detailed images of the body's internal organs and tissues. The positive charge of positrons is crucial for this process to occur, making option B the correct choice.

6. Rectangle: A picture frame measures 15cm by 20cm. What is its perimeter?

• A. 30cm
• B. 55cm
• C. 65cm
• D. 75cm

Correct answer: C

Rationale: Add the lengths of all sides: perimeter = 2 (length + width) = 2 (15cm + 20cm) = 65cm.

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