Nursing Elites

1. Which statement confirms that the cell membrane is selectively permeable?

• A. Receptors are found on a cell's surface.
• B. Cells communicate with each other using cell signals.
• C. Environmental changes can cause a cell to expand or shrink.
• D. Sodium ions must travel through ion channels to enter the cell.

Correct answer: D

Rationale: The correct answer is D because selective permeability is demonstrated by the fact that specific ions, such as sodium, require ion channels to cross the cell membrane. This process allows the cell to control what substances can enter or exit, highlighting the selective nature of the cell membrane. Choices A, B, and C do not directly relate to the concept of selective permeability of the cell membrane. Receptors on a cell's surface (Choice A) are involved in cell signaling rather than selective permeability. Cell communication through signals (Choice B) and environmental changes affecting cell size (Choice C) are not directly related to the selective permeability of the cell membrane, which specifically refers to the regulation of substances passing through the membrane.

2. What is the pathway of oxygenated blood from the lungs?

• A. Lungs to the left atrium, through the mitral valve into the left ventricle, pumped into the aorta upon contraction, then dispersed to tissues via a network of arteries and capillaries
• B. Lungs to the right atrium, through the mitral valve into the right ventricle, pumped into the aorta upon contraction, then dispersed to tissues via a network of arteries and veins
• C. Lungs to the left atrium, directly to the right aorta, then dispersed to tissues via a network of arteries and capillaries
• D. Lungs to the left atrium, through the septal valve, stored in the left ventricles, then dispersed to tissues via a network of arteries and capillaries

Correct answer: A

Rationale: The correct pathway of oxygenated blood from the lungs is as follows: Oxygenated blood travels from the lungs to the left atrium, then passes through the mitral valve into the left ventricle. From there, it is pumped into the aorta upon contraction of the heart and is then dispersed to various tissues throughout the body via a network of arteries and capillaries. Choice B is incorrect as it incorrectly mentions the right atrium and ventricle, which are associated with deoxygenated blood. Choice C is incorrect as it mentions a direct connection to the right aorta, which does not exist in the circulatory system. Choice D is incorrect as it refers to the septal valve (which is not anatomically correct) and storing blood in the left ventricle, which does not occur in the normal circulation of blood.

3. 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 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 integrating signals received from other neurons. The dendrites are covered in synapses, which are the junctions where communication between neurons occurs. The axon, on the other hand, is responsible for transmitting signals away from the cell body. The synapse is the gap between neurons where neurotransmitters are released to facilitate communication. Lastly, the myelin sheath is a fatty layer that insulates and speeds up signal transmission along the axon, helping in the efficient conduction of nerve impulses.

4. What phenomenon explains the bending of light as it passes around an obstacle or through an aperture?

• A. Refraction
• B. Reflection
• C. Diffraction
• D. Dispersion

Correct answer: C

Rationale: Diffraction is the phenomenon that explains the bending of light as it passes around an obstacle or through an aperture. When light encounters an obstacle or passes through an aperture, it diffracts, causing it to bend around the edges. Refraction, on the other hand, occurs when light passes from one medium to another, causing it to change direction. Reflection involves the bouncing back of light rays from a surface, and dispersion is the separation of light into its different colors. Therefore, the correct answer is C, as diffraction specifically addresses the bending of light as it interacts with obstacles or apertures, unlike the other choices that describe different optical phenomena.

5. During inhalation, which muscle contracts to increase the volume of the thoracic cavity, allowing air to flow into the lungs?

• A. Diaphragm
• B. Intercostal muscles
• C. Abdominal muscles
• D. Pectoral muscles

Correct answer: A

Rationale: The diaphragm is the primary muscle responsible for inhalation. When it contracts, it moves downward, increasing the volume of the thoracic cavity and creating a pressure gradient that allows air to flow into the lungs. While the intercostal muscles also play a role in expanding the chest cavity during inhalation, the diaphragm is the main muscle involved in this process. Abdominal muscles and pectoral muscles are not directly involved in the process of inhalation.

Similar Questions