Nursing Elites

1. Deuterium, a stable isotope of hydrogen, has a nucleus containing:

• A. A single proton
• B. A proton and a neutron
• C. Two protons and an electron
• D. Two neutrons

Correct answer: B

Rationale: Deuterium, as an isotope of hydrogen, has an atomic number of 1 and a mass number of 2. The nucleus of deuterium contains one proton (as in all hydrogen atoms) and one neutron, totaling 2 nucleons in the nucleus. Therefore, the correct answer is that deuterium's nucleus contains a proton and a neutron. Choices A, C, and D are incorrect. Deuterium is not just a single proton (A), doesn't have two protons and an electron (C), and doesn't contain two neutrons (D). The correct composition of deuterium's nucleus is one proton and one neutron.

2. Fill in the blanks in the following sentence: Enzymes are ________ molecules that serve as _______ for certain biological reactions.

• A. complex; suppressors
• B. acidic; triggers
• C. small; targets
• D. large; catalysts

Correct answer: D

Rationale: Enzymes are large molecules that act as catalysts, accelerating chemical reactions by lowering the activation energy required for the reactions to occur. In the context of biological reactions, enzymes function as catalysts, not suppressors, triggers, or targets. The use of 'large' and 'catalysts' accurately describes the nature and role of enzymes in facilitating biological processes.

3. What is the primary function of the coronary arteries in the cardiovascular system?

• A. Carry oxygenated blood to the heart muscle
• B. Carry deoxygenated blood from the heart muscle
• C. Pump blood to the lungs for oxygenation
• D. Regulate blood pressure in the systemic circulation

Correct answer: A

Rationale: The primary function of the coronary arteries is to carry oxygenated blood to the heart muscle. Oxygenated blood is crucial for providing nutrients and oxygen to the heart muscle cells, enabling the heart to work efficiently. Without this oxygenated blood supply, the heart muscle may not receive the required nutrients and oxygen, potentially resulting in heart damage or dysfunction. Choices B, C, and D are incorrect as coronary arteries do not carry deoxygenated blood from the heart muscle, pump blood to the lungs for oxygenation, or regulate blood pressure in the systemic circulation. The coronary arteries specifically supply oxygenated blood to the heart muscle to support its function and vitality.

4. What factors can contribute to edema, a condition characterized by swelling due to a buildup of lymph fluid?

• A. Regular exercise
• B. Maintaining a healthy weight
• C. Poor circulation or blockage in the lymphatic system
• D. Proper hydration

Correct answer: C

Rationale: Edema is caused by the accumulation of excess fluid in the body's tissues, leading to swelling. Poor circulation or blockage in the lymphatic system can contribute to the development of edema by impairing the body's ability to properly drain fluid. While regular exercise, maintaining a healthy weight, and proper hydration are crucial for overall health, they are not direct causes of edema. Poor circulation or blockage in the lymphatic system disrupts the normal balance of fluid in the body, resulting in edema. Therefore, the correct factor that can contribute to edema is poor circulation or blockage in the lymphatic system.

5. What is the role of RNA in the regulation of gene expression?

• A. Provides energy for the process
• B. Controls the timing and location of protein synthesis
• C. Translates the genetic code into amino acids
• D. Stores genetic information

Correct answer: B

Rationale: A) RNA does not provide energy for the process of gene expression. Energy is typically provided by molecules like ATP. B) RNA plays a crucial role in controlling the timing and location of protein synthesis through processes like transcriptional regulation, RNA splicing, and post-transcriptional modifications. It helps determine when and where specific proteins are produced in the cell. C) While mRNA translates the genetic code into amino acids during the process of translation, this is not the primary role of RNA in the regulation of gene expression. D) RNA does not store genetic information in the same way that DNA does. DNA is the molecule responsible for storing genetic information in the form of genes. Therefore, option B is the most appropriate choice as it accurately describes the role of RNA in regulating gene expression.

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