Nursing Elites

1. What is the role of RNA interference in silencing genes?

• A. Increases protein production
• B. Promotes gene mutation
• C. Inhibits the expression of specific genes
• D. Repairs damaged DNA

Correct answer: C

Rationale: Rationale: RNA interference (RNAi) is a biological process that involves the silencing of gene expression by inhibiting the translation of mRNA or by degrading mRNA molecules. This mechanism plays a crucial role in regulating gene expression and can be used to selectively silence specific genes. By interfering with the expression of specific genes, RNAi can downregulate protein production from those genes. Therefore, option C, "Inhibits the expression of specific genes," is the correct role of RNA interference in silencing genes.

2. Which of the following is the MOST common symptom of angina pectoris, a condition related to insufficient blood flow to the heart?

• A. Fever and chills.
• B. Chest pain or discomfort.
• C. Sudden onset of severe shortness of breath
• D. Numbness or tingling in the extremities

Correct answer: B

Rationale: The correct answer is B: Chest pain or discomfort. Angina pectoris is characterized by chest pain or discomfort that occurs when the heart muscle does not receive enough oxygen-rich blood. This pain is often described as a squeezing, pressure, heaviness, or tightness in the chest. While other symptoms like fever, chills, shortness of breath, numbness, or tingling in the extremities can occur in various conditions, chest pain is the hallmark symptom of angina pectoris. It is important to recognize this symptom as it may indicate an underlying heart issue and prompt medical attention is crucial.

3. Which element has the highest melting point of any element?

• A. Tungsten
• B. Iron
• C. Platinum
• D. Carbon

Correct answer: D

Rationale: Diamond's strong covalent bonds between carbon atoms make it incredibly resistant to heat and pressure, giving it the highest melting point.

4. Which of the following is a pair of nerves that originates from the brain?

• A. Spinal nerves
• B. Olfactory nerves
• C. Sciatic nerve
• D. Optic nerve

Correct answer: B

Rationale: The correct answer is B, Olfactory nerves, because they are a pair of cranial nerves that originate from the brain and are responsible for the sense of smell. Spinal nerves (option A) originate from the spinal cord, not the brain. The sciatic nerve (option C) is a large nerve that runs from the lower back down the back of each leg and also originates from the spinal cord, not the brain. The optic nerve (option D) is a cranial nerve that connects the eye to the brain, but it is not a pair of nerves that originates from the brain. Therefore, the olfactory nerves are the only pair of nerves listed that specifically originate from the brain.

5. Which part of the neuron receives incoming signals from other neurons and conducts them toward the cell body?

• A. Axon
• B. Dendrite
• C. Synapse
• D. Myelin sheath

Correct answer: b

Rationale: The correct answer is B: Dendrite. Dendrites are the part of the neuron that receive incoming signals from other neurons and conduct them toward the cell body. They play a crucial role in communication between neurons by receiving neurotransmitters released from neighboring neurons. Axons transmit signals away from the cell body, synapses are the junctions where neurons communicate with each other, and myelin sheath is a fatty insulation that surrounds and protects axons. Therefore, in this scenario, dendrites are specifically responsible for receiving and conducting incoming signals towards the cell body.

6. A guitar string vibrates at a fundamental frequency of 440 Hz. What is the frequency of the second harmonic (first overtone)?

• A. 220 Hz
• B. 440 Hz
• C. 880 Hz
• D. 1760 Hz

Correct answer: C

Rationale: Harmonics have frequencies that are multiples of the fundamental frequency. The second harmonic has a frequency twice the fundamental, so it's 440 Hz * 2 = 880 Hz.

Similar Questions