Nursing Elites

1. What is the relationship between mass and weight on Earth's surface?

• A. Mass and weight are equal
• B. Mass is greater than weight
• C. Weight is greater than mass
• D. Mass and weight are not related

Correct answer: a

Rationale: On Earth's surface, mass and weight are directly proportional but not equal, as weight is the force due to gravity acting on an object's mass.

2. 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.

3. Coronary arteries are responsible for:

• A. Delivering oxygenated blood throughout the body.
• B. Supplying oxygenated blood to the heart muscle itself.
• C. Carrying deoxygenated blood back to the heart.
• D. Regulating blood pressure through vasoconstriction and vasodilation.

Correct answer: B

Rationale: The correct answer is B: 'Supplying oxygenated blood to the heart muscle itself.' Coronary arteries are specialized blood vessels that branch off the aorta and provide oxygenated blood to the heart muscle. This is crucial for the heart to function properly and maintain its own blood supply separate from the systemic circulation. The other options are incorrect because delivering oxygenated blood throughout the body is the role of the systemic circulation and not specific to coronary arteries. Carrying deoxygenated blood back to the heart is the function of veins, while regulating blood pressure through vasoconstriction and vasodilation is primarily controlled by arteries in general, not just the coronary arteries.

4. The innate immune system provides a non-specific first line of defense. What are some physical barriers that contribute to the innate immune system?

• A. Antibodies
• B. Phagocytes
• C. Skin and mucous membranes
• D. Memory B cells

Correct answer: C

Rationale: The correct answer is C: "Skin and mucous membranes." The innate immune system consists of physical barriers, such as the skin and mucous membranes, that act as the first line of defense against pathogens. These barriers prevent pathogens from entering the body and play a crucial role in protecting against infections. Antibodies (option A) are part of the adaptive immune response, not the innate immune system. Phagocytes (option B) are cells that engulf and destroy pathogens, which are part of the innate immune system. Memory B cells (option D) are specific to the adaptive immune response and are not considered part of the innate immunity that provides the initial, non-specific defense.

5. Antibodies, crucial for immune defense, are produced by:

• A. Neutrophils
• B. Lymphocytes
• C. Monocytes
• D. Basophils

Correct answer: B

Rationale: The correct answer is B: Lymphocytes. Antibodies, also known as immunoglobulins, are produced by B lymphocytes (B cells) as a key component of the adaptive immune response. These specialized cells play a crucial role in recognizing and neutralizing pathogens, thereby providing immunity against infections. Neutrophils (A) are a type of white blood cell involved in innate immunity and phagocytosis. Monocytes (C) are another type of white blood cell that can differentiate into macrophages, which are important in phagocytosis and antigen presentation. Basophils (D) are involved in allergic responses and inflammation through the release of histamine. Lymphocytes, particularly B cells, are primarily responsible for antibody production in response to pathogens and foreign substances.

6. Which verb tense best fits the blank: "By next month, she _____ the project for a year."

• A. will have been working on
• B. will work on
• C. has been working on
• D. had worked on

Correct answer: C

Rationale: The sentence emphasizes the completed duration of the project by next month, requiring the present perfect continuous tense.

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