Nursing Elites

1. Which of the following properties is NOT characteristic of a covalent bond?

• A. Sharing of electrons between atoms
• B. High melting and boiling points
• C. Low electrical conductivity in solid state
• D. Directional bonding

Correct answer: B

Rationale: Covalent bonds are formed by the sharing of electrons between atoms. This sharing results in the formation of molecules with directional bonding, where the atoms are held together in a specific orientation. Covalent compounds generally have low melting and boiling points compared to ionic compounds, as the intermolecular forces in covalent compounds are weaker. Additionally, covalent compounds do not conduct electricity in the solid state because the electrons are localized between the atoms and not free to move and carry charge.

2. Which term refers to the condition where a muscle shortens in length while generating force, leading to movement at a joint?

• A. Isometric contraction
• B. Eccentric contraction
• C. Isotonic contraction
• D. Concentric contraction

Correct answer: d

Rationale: The correct answer is D: Concentric contraction. Concentric contraction occurs when a muscle shortens in length while generating force, resulting in movement at a joint. This type of contraction is commonly seen when lifting a weight in a bicep curl, for example. Isometric contraction, option A, refers to when the muscle generates force without changing length, eccentric contraction, option B, is when the muscle lengthens while generating force, and isotonic contraction, option C, involves the muscle maintaining a constant tension while changing length. Therefore, in the context of muscle movement and joint action, concentric contraction best describes the condition described in the question.

3. Alpha waves, characteristic of quiet wakefulness and relaxation, have a frequency range of:

• A. 0.5-4 Hz
• B. 4-8 Hz
• C. 8-13 Hz
• D. 13-30 Hz

Correct answer: B

Rationale: Alpha waves are typically associated with relaxed wakefulness and quiet, non-arousing states. They have a frequency range of 8-13 Hz. This frequency range is slower than beta waves (13-30 Hz) associated with active thinking and concentration, making option C the correct answer. Options A (0.5-4 Hz) and D (13-30 Hz) do not fall within the typical range of alpha waves. Therefore, option B is the most appropriate choice for the frequency range of alpha waves, reflecting the brain's state during relaxation and quiet wakefulness.

4. What is the primary function of hair on the human body?

• A. Insulation
• B. Sensory perception
• C. Protection
• D. Vitamin D synthesis

Correct answer: A

Rationale: The primary function of hair on the human body is insulation. Hair acts as a protective layer to help regulate body temperature by trapping heat close to the skin. This insulation property is especially important in colder climates to prevent excessive heat loss from the body. While hair can also provide some level of protection from external elements and minor injuries, its main role is to insulate the body. Sensory perception is mainly attributed to nerve endings in the skin rather than hair. Vitamin D synthesis is primarily dependent on exposure to sunlight rather than hair. Therefore, option A, insulation, is the correct answer.

5. What is the acceleration of an object moving at a constant speed of 20 m/s if it comes to a complete stop within 5 seconds?

• A. 0 m/s² (no acceleration)
• B. 4 m/s²
• C. -4 m/s²
• D. Information insufficient

Correct answer: C

Rationale: The acceleration can be calculated using the formula: acceleration = (final velocity - initial velocity) / time. In this case, the final velocity is 0 m/s (as the object comes to a complete stop), the initial velocity is 20 m/s, and the time taken is 5 seconds. Plugging these values into the formula, we get acceleration = (0 m/s - 20 m/s) / 5 s = -20 m/s / 5 s = -4 m/s². Therefore, the acceleration is -4 m/s².

6. A medication dosage is listed as 1/4 gram. What is the equivalent dosage in milligrams (1 gram = 1000 milligrams)?

• A. 125mg
• B. 250mg
• C. 375mg
• D. 500mg

Correct answer: D

Rationale: Multiply the gram dosage (1/4) by the conversion factor (1000mg/gram) to get 250 milligrams.

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