Nursing Elites

1. What is the basic unit of heredity?

• A. Chromosome
• B. Cell
• C. Gene
• D. Organ

Correct answer: C

Rationale: A gene is the basic unit of heredity that carries the instructions for making proteins, which determine an organism's traits. Genes are segments of DNA located on chromosomes within the cell. While chromosomes contain many genes, a gene itself is the fundamental unit of heredity responsible for passing on genetic information from one generation to the next. Cells are the basic structural and functional units of living organisms, but genes specifically carry genetic information. Organs are composed of tissues and serve specific functions within an organism, but they are not the basic unit of heredity.

2. What is the waxy or oily substance produced by sebaceous glands that helps lubricate the skin and hair?

• A. Keratin
• B. Melanin
• C. Sebum
• D. Sweat

Correct answer: C

Rationale: Sebum is the waxy or oily substance produced by sebaceous glands. It helps lubricate the skin and hair, keeping them moisturized and protected. Keratin is a protein that makes up hair, skin, and nails, providing structure and strength. Melanin is a pigment that gives color to the skin, hair, and eyes, providing protection against UV radiation. Sweat is a watery fluid produced by sweat glands to help regulate body temperature by cooling the body through evaporation.

3. What step of the scientific method must come before generating a hypothesis?

• A. Collecting and organizing data.
• B. Communicating the results in a scientific journal.
• C. Conducting an experiment.
• D. Researching previous studies for background.

Correct answer: D

Rationale: The correct answer is D, 'Researching previous studies for background.' Before formulating a hypothesis, it is essential to review existing literature, studies, and information related to the topic to understand the context and identify gaps in knowledge. This step helps researchers build on existing knowledge and formulate a clear hypothesis based on the information gathered. Choices A, B, and C are incorrect because they come after the step of researching previous studies and developing a hypothesis. Collecting and organizing data, conducting an experiment, and communicating results typically follow the hypothesis generation step in the scientific method.

4. Which of the following is an example of a nonpolar solvent?

• A. Water
• B. Ethanol
• C. Acetone
• D. Hydrochloric acid

Correct answer: B

Rationale: - Water (option A) is a polar solvent due to its uneven distribution of charge, with the oxygen atom being partially negative and the hydrogen atoms being partially positive. - Ethanol (option B) is a nonpolar solvent because it has a symmetrical molecular structure that does not result in significant charge separation. - Acetone (option C) is a polar solvent as it contains a carbonyl group that results in a partial negative charge on the oxygen atom. - Hydrochloric acid (option D) is a polar solvent due to the presence of the highly electronegative chlorine atom, which results in a partial negative charge.

5. Which of the following substances is typically a good conductor of electricity when dissolved in water?

• A. Sugar
• B. Sodium chloride
• C. Olive oil
• D. Oxygen gas

Correct answer: B

Rationale: Sodium chloride (table salt) is typically a good conductor of electricity when dissolved in water because it dissociates into ions (sodium cations and chloride anions) that can carry an electric current. Sugar (choice A), olive oil (choice C), and oxygen gas (choice D) do not dissociate into ions in water and therefore are not good conductors of electricity. Sugar does not dissociate into ions in water, so it cannot conduct electricity. Olive oil and oxygen gas are nonpolar substances and do not ionize in water, making them poor conductors of electricity.

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