Nursing Elites

1. Which of the following is a consequence of bone marrow failure?

• A. Seizures.
• B. Pancytopenia.
• C. Paraplegia.
• D. Pathologic fractures.

Correct answer: B

Rationale: The corrected question focuses on the consequence of bone marrow failure, which is pancytopenia. Bone marrow failure results in decreased production of red blood cells, white blood cells, and platelets, leading to pancytopenia. This condition manifests as fatigue, weakness, increased infection susceptibility, and bleeding tendencies. Paraplegia, seizures, and pathologic fractures are not typical outcomes of bone marrow failure. Paraplegia is associated with spinal cord injury, seizures with neurological disorders, and pathologic fractures with conditions like osteoporosis or bone tumors.

2. Neurotransmitters send chemical messages across the gap between one neuron and another through which of the following structures?

• A. Schwann cell
• B. ganglion
• C. synapse
• D. axon

Correct answer: C

Rationale: Neurotransmitters send chemical messages across the gap between one neuron and another through a structure called the synapse. The synapse is a specialized junction where the axon of one neuron meets the dendrite or cell body of another neuron. Neurotransmitters are released from the axon terminal of the presynaptic neuron and travel across the synaptic cleft to bind to receptors on the postsynaptic neuron, transmitting the signal between the two neurons. Choice A, Schwann cell, is incorrect as Schwann cells are responsible for producing myelin sheath around axons in the peripheral nervous system, not for transmitting neurotransmitters between neurons. Choice B, ganglion, is incorrect as ganglia are clusters of nerve cell bodies outside the central nervous system and do not directly participate in the transmission of chemical messages between neurons. Choice D, axon, is incorrect as the axon is a long, slender projection of a neuron that conducts electrical impulses away from the cell body and towards the axon terminals, where neurotransmitters are released into the synapse, but it is not the structure across which neurotransmitters travel to communicate between neurons.

3. Which of the following structures is responsible for filtering lymph and supporting the immune system?

• A. Kidneys
• B. Lymph nodes
• C. Pancreas
• D. Liver

Correct answer: B

Rationale: Lymph nodes are responsible for filtering lymph and supporting the immune system. They contain immune cells that trap and destroy pathogens, making them crucial in immune response. The other choices, kidneys, pancreas, and liver, do not play a direct role in filtering lymph or supporting the immune system. The kidneys filter blood to remove waste and regulate electrolytes, the pancreas is involved in digestion and blood sugar regulation, and the liver is primarily responsible for detoxification and metabolism.

4. What is the main function of valence electrons in chemical bonding?

• A. They are responsible for holding the nucleus together.
• B. They are involved in forming bonds with other atoms.
• C. They determine the element's physical properties.
• D. They play no role in chemical reactions.

Correct answer: B

Rationale: Valence electrons are the electrons in the outermost energy level of an atom. These electrons are involved in forming bonds with other atoms, which is crucial for chemical bonding. By participating in bonding, valence electrons determine an atom's ability to form compounds and engage in chemical reactions. Therefore, the primary function of valence electrons is to facilitate the formation of bonds between atoms, making option B the correct answer. Choices A, C, and D are incorrect because valence electrons primarily influence chemical bonding by participating in the formation of bonds between atoms, rather than holding the nucleus together, determining physical properties, or having no role in chemical reactions.

5. What is molarity a measure of in a solution?

• A. Volume of the solvent
• B. Amount of solute
• C. Concentration of solute
• D. Temperature of the solution

Correct answer: C

Rationale: Molarity is a measure of the concentration of a solute in a solution. It is defined as the number of moles of solute per liter of solution. Molarity is not a measure of the volume of the solvent (choice A), the amount of solute (choice B), or the temperature of the solution (choice D). Therefore, the correct answer is the concentration of solute (choice C) as molarity specifically quantifies the solute concentration in a solution.

Similar Questions