Nursing Elites

1. Which of the following statements about prions is TRUE?

• A. They are composed of proteins only
• B. They are easily destroyed by common disinfectants
• C. hey are a type of antibiotic
• D. They are a live organism

Correct answer: A

Rationale: A) This statement is true. Prions are infectious agents composed entirely of protein, lacking nucleic acids such as DNA or RNA. They are known for causing neurodegenerative diseases in animals and humans. B) This statement is false. Prions are not easily destroyed by common disinfectants due to their unique structure and resistance to conventional sterilization methods. C) This statement is false. Prions are not a type of antibiotic. They are a distinct class of infectious agents. D) This statement is false. Prions are not live organisms but rather misfolded proteins that can induce abnormal folding in normal proteins, leading to disease.

2. Which term describes the ability of a muscle to return to its original length and shape after being stretched or contracted?

• A. Contractility
• B. Elasticity
• C. Extensibility
• D. Excitability

Correct answer: B

Rationale: Elasticity is the correct term that describes the ability of a muscle to return to its original length and shape after being stretched or contracted. Contractility refers to the ability of a muscle to contract or shorten. Extensibility is the ability of a muscle to be stretched. Excitability is the ability of a muscle to receive and respond to stimuli. Therefore, the correct answer is 'Elasticity' as it specifically relates to the muscle's ability to regain its original form.

3. Which of the following is a strong base commonly used in cleaning products?

• A. Sodium hydroxide (NaOH)
• B. Ammonium hydroxide (NHâ‚„OH)
• C. Calcium hydroxide (Ca(OH)â‚‚)
• D. Potassium hydroxide (KOH)

Correct answer: A

Rationale: Sodium hydroxide (NaOH) is a strong base commonly used in cleaning products due to its effectiveness in breaking down grease and fats. It is known for its corrosive properties and is commonly found in drain cleaners and oven cleaners. While ammonium hydroxide, calcium hydroxide, and potassium hydroxide are also bases, they are not as strong as sodium hydroxide and are not as commonly used in cleaning products. Ammonium hydroxide is more commonly found in household cleaning products for its disinfectant properties, calcium hydroxide is used in agriculture and construction, and potassium hydroxide is often used in industries like soap manufacturing and biodiesel production.

4. Which of the following stimulates adaptive immunity?

• A. Peptides
• B. Phagocytes
• C. Prions
• D. Platelets

Correct answer: C

Rationale: The correct answer is C: Prions. Prions are infectious proteins that can stimulate an adaptive immune response by triggering the production of specific antibodies. Peptides are fragments of proteins and can be processed and presented by antigen-presenting cells to activate T cells, which play a role in adaptive immunity. Phagocytes, such as macrophages, are part of the innate immune system and are involved in engulfing and destroying pathogens, but they do not directly stimulate adaptive immunity. Platelets are primarily involved in blood clotting and are not directly related to stimulating adaptive immunity.

5. What type of genetic variation is caused by changes in the DNA sequence?

• A. Epigenetic variation
• B. Phenotypic variation
• C. Genotypic variation
• D. Behavioral variation

Correct answer: C

Rationale: A) Epigenetic variation refers to changes in gene expression that do not involve alterations in the DNA sequence itself. These changes can be influenced by environmental factors. B) Phenotypic variation refers to differences in observable traits or characteristics of an organism, which can be influenced by both genetic and environmental factors. C) Genotypic variation is caused by changes in the DNA sequence, such as mutations or genetic recombination. These changes directly impact the genetic information carried by an organism. D) Behavioral variation refers to differences in behavior among individuals of the same species, which can be influenced by genetic, environmental, and experiential factors.

Similar Questions