Nursing Elites

1. Which of the following components is found in DNA?

• A. Uracil
• B. Deoxyribose
• C. Guanine
• D. Phosphate group

Correct answer: B

Rationale: The correct answer is B: Deoxyribose. DNA is composed of nucleotides containing deoxyribose sugar, phosphate group, and nitrogenous bases (adenine, thymine, guanine, and cytosine). Deoxyribose is the sugar component specific to DNA, while ribose is found in RNA. Guanine (choice C) is a nitrogenous base present in both DNA and RNA. Uracil (choice A) is a nitrogenous base specific to RNA, replacing thymine found in DNA. The phosphate group (choice D) is an essential part of nucleotides in both DNA and RNA, providing the backbone structure for the nucleic acid chains.

2. What is the process of converting lactic acid back into pyruvate called?

• A. Glycolysis
• B. Gluconeogenesis
• C. Cori cycle
• D. Oxidative phosphorylation

Correct answer: C

Rationale: A) Glycolysis is the process of breaking down glucose into pyruvate. B) Gluconeogenesis is the process of synthesizing glucose from non-carbohydrate sources. C) The Cori cycle is the process by which lactic acid produced by anaerobic metabolism in muscles is transported to the liver and converted back into glucose or pyruvate. D) Oxidative phosphorylation is the process by which ATP is synthesized using energy derived from the transfer of electrons in the electron transport chain.

3. Which of the following statements regarding macrophages is incorrect?

• A. They are found abundantly in the blood
• B. They are larger than neutrophils
• C. They are long-lived
• D. They are made in the bone marrow as monocytes, called macrophages once they reach organs

Correct answer: A

Rationale: The correct answer is A. Macrophages are not found abundantly in the blood; they are present in tissues and organs. Macrophages are tissue-resident immune cells that play a key role in immune responses and are derived from monocytes produced in the bone marrow. Choice B is correct as macrophages are larger than neutrophils. Choice C is correct as macrophages are long-lived cells. Choice D is correct as macrophages originate in the bone marrow as monocytes and differentiate into macrophages once they migrate to various tissues and organs.

4. The shimmering image of water seen on a hot road is a well-known example of:

• A. Reflection
• B. Refraction
• C. Interference
• D. Polarization

Correct answer: B

Rationale: The shimmering image of water seen on a hot road is a result of refraction, not reflection. Refraction is the bending of light as it passes from one medium to another of different optical density. In this case, the hot air just above the road has a different density than the cooler air above it, causing light to bend and create the illusion of water on the road. Refraction is the most suitable explanation for this phenomenon, as it involves the bending of light rays due to the change in the medium's optical density, producing the visual effect observed on the hot road. Reflection, interference, and polarization do not involve the bending of light due to changes in optical density and are not applicable to the scenario described on the hot road.

5. Which organelle in the cell is responsible for producing energy in the form of ATP?

• A. Nucleus
• B. Mitochondria
• C. Ribosome
• D. Golgi apparatus

Correct answer: B

Rationale: The correct answer is B: Mitochondria. Mitochondria are known as the powerhouses of the cell and are responsible for producing energy in the form of ATP through cellular respiration. ATP is the primary energy currency of the cell, powering various cellular activities. The nucleus (choice A) is responsible for housing the cell's genetic material but is not involved in ATP production. Ribosomes (choice C) are involved in protein synthesis, not energy production. The Golgi apparatus (choice D) is responsible for modifying, sorting, and packaging proteins for secretion, not for ATP production.

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