Nursing Elites

1. Which of the following correctly describes a strong acid?

• A. A strong acid completely ionizes in water.
• B. A strong acid donates more than one proton.
• C. A strong acid contains at least one metal atom.
• D. A strong acid will not decompose.

Correct answer: A

Rationale: The correct answer is A. A strong acid is defined as an acid that completely ionizes in water, meaning it dissociates fully into its constituent ions in solution. This characteristic differentiates strong acids from weak acids, which do not fully dissociate in water. Choice B is incorrect because the number of protons donated does not solely define the strength of an acid. Choice C is incorrect as strong acids are not defined by the presence of metal atoms, and Choice D is incorrect because all acids can decompose, but the strength of the acid is based on its ability to ionize in water.

2. Centrioles are structures involved in cell division. What is their specific role?

• A. Forming the nuclear envelope
• B. Replicating DNA
• C. Organizing microtubules during cell division
• D. Protein synthesis

Correct answer: C

Rationale: Centrioles are involved in organizing microtubules during cell division, specifically in forming the mitotic spindle. The mitotic spindle is crucial for the proper alignment and separation of chromosomes during cell division, ensuring the accurate distribution of genetic material to daughter cells. Choice A, forming the nuclear envelope, is incorrect as centrioles do not have a direct role in this process. Choice B, replicating DNA, is incorrect as centrioles are not involved in DNA replication. Choice D, protein synthesis, is incorrect as centrioles do not play a role in protein synthesis.

3. What is a mutation?

• A. A change in the DNA sequence
• B. A type of protein
• C. A normal part of the DNA replication process
• D. A harmless variation in DNA

Correct answer: A

Rationale: A mutation is defined as a change in the DNA sequence, which can occur due to various factors such as errors during DNA replication, exposure to mutagens (e.g., chemicals, radiation), or spontaneous changes. These alterations can lead to modifications in the genetic information carried by an organism, resulting in effects that can range from harmless variations to causing genetic disorders or diseases. Mutations play a crucial role in genetic diversity and evolution. Choices B, C, and D are incorrect as they do not accurately define what a mutation is. Option B is incorrect because mutations are not a type of protein but rather changes in DNA. Option C is incorrect because while mutations can occur during DNA replication, they are not considered a 'normal' part of the process as they can lead to genetic variations. Option D is incorrect because mutations can have a wide range of effects and are not always harmless variations.

4. Which hormone is released by the adrenal glands in response to stress?

• A. Insulin
• B. Cortisol
• C. Adrenaline
• D. Glucagon

Correct answer: C

Rationale: Adrenaline is the correct answer. It is released by the adrenal glands in response to stress to prepare the body for the 'fight or flight' response. Adrenaline increases heart rate, dilates airways, and mobilizes energy stores to help the body deal with the perceived threat. Insulin (Choice A) is produced by the pancreas to regulate blood sugar levels, not in response to stress. Cortisol (Choice B) is another hormone released by the adrenal glands in response to stress, but it primarily helps regulate metabolism and immune response. Glucagon (Choice D) is also produced by the pancreas to increase blood sugar levels when they are low, not by the adrenal glands in response to stress.

5. An object is moving in a circle at constant speed. Is there a net force acting on it?

• A. Yes, always
• B. No, never
• C. Only if its speed is changing
• D. Only if its direction is changing

Correct answer: D

Rationale: When an object is moving in a circle at a constant speed, there is a net force acting on it. This net force is directed towards the center of the circle and is responsible for continuously changing the direction of the object's velocity, even though the speed remains constant. Therefore, the correct answer is D because the net force is required to change the direction of the object's motion in a circular path. Choices A, B, and C are incorrect because the presence of a net force is necessary to continuously change the object's direction as it moves in a circular path, irrespective of changes in speed.

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