Nursing Elites

1. Which term refers to the measure of the mass of a substance per unit volume and is commonly expressed in kilograms per cubic meter?

• A. Mass
• B. Weight
• C. Density
• D. Volume

Correct answer: C

Rationale: Density is the measure of the mass of a substance per unit volume and is commonly expressed in kilograms per cubic meter. Mass refers to the amount of matter in an object, weight is the force of gravity acting on an object, and volume is the amount of space an object occupies. In this context, density is the correct term for expressing the measure of mass per unit volume, making it the most appropriate choice among the options provided.

2. What is the length of DNA that can code for a particular protein?

• A. Chromosome
• B. Nucleotide
• C. Gene
• D. Ribosome

Correct answer: C

Rationale: The correct answer is C: Gene. A gene is a specific segment of DNA that contains the information necessary to produce a particular protein. Genes are responsible for coding proteins, and each gene carries the instructions for a specific protein. Chromosomes consist of many genes and are not a specific length that codes for a protein. Nucleotides are the building blocks of DNA and are not a length that codes for a protein. Ribosomes are cellular organelles involved in protein synthesis and do not directly code for proteins.

3. Which structure in the respiratory system is responsible for preventing food and liquids from entering the trachea during swallowing?

• A. Bronchi
• B. Larynx
• C. Alveoli
• D. Pharynx

Correct answer: B

Rationale: The larynx, housing the epiglottis, a flap of tissue, is the structure responsible for preventing food and liquids from entering the trachea during swallowing. It acts as a protective barrier, covering the trachea to ensure that ingested substances are directed to the esophagus. The bronchi are the primary airway passages that branch from the trachea into the lungs. Alveoli are tiny air sacs in the lungs where gas exchange occurs, facilitating the exchange of oxygen and carbon dioxide. The pharynx is the passage connecting the mouth and nasal cavity to the esophagus and trachea.

4. What is the primary function of the cell membrane?

• A. To provide structural support for the cell
• B. To transport substances in and out of the cell
• C. To synthesize proteins and lipids
• D. To store genetic material

Correct answer: B

Rationale: The primary function of the cell membrane, also known as the plasma membrane, is to regulate the movement of substances in and out of the cell. It acts as a selectively permeable barrier, allowing specific molecules to pass through while blocking others. This role is crucial for maintaining the internal environment of the cell by enabling essential nutrients to enter and waste products to exit. While the cell membrane provides some structural support for the cell, its main function is substance transport. Protein and lipid synthesis predominantly occur in organelles like the endoplasmic reticulum and Golgi apparatus, and storing genetic material is the nucleus's responsibility. Therefore, choices C (To synthesize proteins and lipids) and D (To store genetic material) are incorrect as these functions are carried out by other cell organelles, not the cell membrane.

5. 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: C

Rationale: Alpha waves are neural oscillations in the frequency range of 8-13 Hz, which are typically associated with a state of quiet wakefulness and relaxation. Option C, 8-13 Hz, is the correct frequency range for alpha waves. Choices A, B, and D are incorrect as they do not fall within the specific frequency range characteristic of alpha waves.

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