Nursing Elites

1. Which part of the neuron insulates and speeds up the transmission of nerve impulses along the axon?

• A. Dendrite
• B. Myelin sheath
• C. Synapse
• D. Cell body

Correct answer: B

Rationale: The myelin sheath is a fatty layer that surrounds the axon of a neuron, providing insulation and speeding up the transmission of nerve impulses. This insulation helps prevent the loss of electrical signals as they travel along the axon, allowing for faster and more efficient communication within the nervous system. Dendrites are branching extensions of a neuron that receive signals from other neurons, the synapse is the junction between two neurons where communication occurs, and the cell body contains the nucleus and organelles of the neuron, but none of these structures provide insulation for the transmission of nerve impulses along the axon.

2. What is the purpose of sodium bicarbonate when released into the lumen of the small intestine?

• A. It works to chemically digest fats in the chyme.
• B. It decreases the pH of the chyme to prevent harm to the intestine.
• C. It works to chemically digest proteins in the chyme.
• D. It increases the pH of the chyme to prevent harm to the intestine.

Correct answer: D

Rationale: Sodium bicarbonate, when released into the lumen of the small intestine, functions to increase the pH of the acidic chyme coming from the stomach. This increase in pH helps neutralize the acidity of the chyme, creating a more optimal environment for the digestive enzymes in the small intestine to function properly. Maintaining a slightly basic pH in the small intestine is crucial for overall digestion and absorption of nutrients. Choices A, B, and C are incorrect. Sodium bicarbonate does not chemically digest fats or proteins in the chyme, and it does not decrease the pH of the chyme as it actually increases the pH to prevent harm to the intestine.

3. A commuter survey counts the people riding in cars on a highway in the morning. Each car contains only one man, only one woman, or both one man and one woman. Out of 25 cars, 13 contain a woman and 20 contain a man. How many contain both a man and a woman?

• A. 4
• B. 7
• C. 8
• D. 13

Correct answer: C

Rationale: Let's denote the number of cars containing only a man as M, only a woman as W, and both a man and a woman as B. Given that there are 25 cars in total, we have: M + W + B = 25 From the information provided, we know that 13 cars contain a woman (W) and 20 cars contain a man (M). Since each car contains either one man, one woman, or both, the cars that contain both a man and a woman (B) are counted once in each of the M and W categories. Therefore, to find out how many cars contain both a man and a woman, we need to subtract the number of cars that contain only a man and only a woman from the total cars. M + B = 20 (as 20 cars contain a man) W + B = 13 (as 13 cars contain a woman) Solving the above two equations simultaneously, we get: M = 12, W = 5, B = 8 Therefore, 8 cars contain both a man and a woman. Hence, the correct answer is 8. Choice A, B, and D are incorrect as they do not reflect the correct calculation based on the information provided.

4. Which of the following is a characteristic of alkenes?

• A. They have a double bond between carbon atoms.
• B. They are saturated hydrocarbons.
• C. They contain only single bonds.
• D. They are derivatives of ammonia.

Correct answer: A

Rationale: Alkenes are hydrocarbons that contain at least one carbon-carbon double bond. This double bond is a key characteristic that distinguishes alkenes from other types of hydrocarbons. Option A correctly identifies this defining feature of alkenes, making it the correct answer. Choices B, C, and D are incorrect. Choice B is incorrect because alkenes are unsaturated hydrocarbons due to the presence of double bonds. Choice C is incorrect as alkenes do not contain only single bonds; they have at least one double bond. Choice D is incorrect because alkenes are not derivatives of ammonia; they are a distinct class of organic compounds with carbon-carbon double bonds.

5. What is the acceleration due to gravity near the Earth's surface?

• A. 9.8 meters per second squared (m/s²)
• B. 6.3 meters per second squared (m/s²)
• C. 5.0 meters per second squared (m/s²)
• D. 12.5 meters per second squared (m/s²)

Correct answer: A

Rationale: The acceleration due to gravity near the Earth's surface is approximately 9.8 m/s². This value is commonly used in physics calculations and represents the rate at which an object accelerates towards the Earth when in free fall. The acceleration due to gravity is a constant value near the Earth's surface and affects the motion of all objects. Choices B, C, and D are incorrect as they do not represent the standard value of 9.8 m/s². Understanding the correct value of acceleration due to gravity is fundamental in physics as it helps in solving various problems related to motion, forces, and energy.

Similar Questions