Nursing Elites

1. Which layer of the skin is responsible for new skin cell production?

• A. Stratum corneum
• B. Stratum basale
• C. Stratum granulosum
• D. Stratum spinosum

Correct answer: B

Rationale: The correct answer is B, Stratum basale. The stratum basale, also known as the basal layer or stratum germinativum, is the deepest layer of the epidermis and is responsible for new skin cell production through cell division. It contains basal cells that continuously divide to produce new keratinocytes, which move up through the layers of the epidermis. Choice A, Stratum corneum, is the outermost layer of the epidermis consisting of dead cells filled with keratin. It serves a protective function but is not involved in new skin cell production. Choice C, Stratum granulosum, is a layer of the epidermis where keratinocytes undergo changes in their structure and composition. It is involved in the process of keratinization but not in new skin cell production. Choice D, Stratum spinosum, is a layer of the epidermis where cells become interconnected by desmosomes. While it plays a role in providing strength and support to the epidermis, it is not primarily responsible for new skin cell production.

2. Which muscles play a significant role in the process of forced exhalation by contracting to reduce the thoracic cavity volume?

• A. Diaphragm
• B. External intercostal muscles
• C. Internal intercostal muscles
• D. Abdominal muscles

Correct answer: D

Rationale: The abdominal muscles play a significant role in forced exhalation by contracting to reduce the thoracic cavity volume. When these muscles contract, the pressure within the thoracic cavity increases, assisting in the expulsion of air from the lungs. This action helps to compress the abdomen and push the diaphragm upwards, further decreasing the volume of the thoracic cavity and aiding in the exhalation process. The diaphragm (Choice A) is mainly involved in inhalation by contracting and moving downward to increase thoracic cavity volume. External intercostal muscles (Choice B) and internal intercostal muscles (Choice C) are primarily involved in the process of inhalation by expanding the thoracic cavity during normal breathing, rather than forced exhalation.

3. Find the lowest coefficients that will balance the following combustion equation: __C H + __O2 → __CO2 + __H2O

• A. 1:5:5:2
• B. 4:10:20:8
• C. 2:9:10:4
• D. 2:5:10:4

Correct answer: C

Rationale: To balance the combustion equation CxHy + O2 → xCO2 + y/2 H2O, we need to balance the carbon and hydrogen atoms. The balanced equation for the given combustion is: 2C H4 + 9O2 → 2CO2 + 4H2O. This means that the correct coefficients are 2:9:10:4, which corresponds to choice C. Choice A (1:5:5:2) does not balance the equation correctly, choice B (4:10:20:8) has excessive oxygen and does not balance the equation, and choice D (2:5:10:4) does not provide the correct ratio of oxygen to balance the equation.

4. Which vitamin is synthesized in the skin upon exposure to sunlight?

• A. Vitamin A
• B. Vitamin C
• C. Vitamin D
• D. Vitamin E

Correct answer: C

Rationale: Vitamin D is synthesized in the skin upon exposure to sunlight. When the skin is exposed to sunlight, a form of cholesterol in the skin is converted into vitamin D3 (cholecalciferol) through a series of chemical reactions. Vitamin D plays a crucial role in calcium absorption and bone health. Choice A, Vitamin A, is not synthesized in the skin upon exposure to sunlight; it is obtained through dietary sources. Choice B, Vitamin C, is not synthesized in the skin upon exposure to sunlight either. Vitamin C is obtained through dietary sources like fruits and vegetables. Choice D, Vitamin E, is not synthesized in the skin upon exposure to sunlight. Vitamin E is a fat-soluble vitamin that acts as an antioxidant and is obtained through dietary sources like nuts, seeds, and vegetable oils.

5. Which of the following structures is responsible for transmitting electrical impulses in the nervous system?

• A. Neuron
• B. Axon
• C. Myelin
• D. Dendrite

Correct answer: A

Rationale: The correct answer is A: Neuron. Neurons are specialized cells that transmit electrical impulses in the nervous system. While the axon is the part responsible for conducting these impulses over long distances, it is the neuron as a whole that is ultimately responsible for transmitting electrical impulses. Myelin is a fatty substance that surrounds and insulates axons, speeding up signal transmission. Dendrites, on the other hand, receive signals from other neurons. Therefore, although the axon plays a significant role in transmission, the neuron is the fundamental unit responsible for transmitting electrical impulses in the nervous system.

Similar Questions