Nursing Elites

1. What is the building block of DNA?

• A. Amino acid
• B. Nucleotide
• C. Phosphate group
• D. Fatty acid

Correct answer: B

Rationale: - Amino acids are the building blocks of proteins, not DNA. - Nucleotide is the correct building block of DNA. A nucleotide consists of a sugar (deoxyribose in DNA), a phosphate group, and a nitrogenous base (adenine, thymine, cytosine, or guanine). - The option 'C) Phosphate group' is incorrect as it is only part of a nucleotide, not the complete building block of DNA. - Fatty acids are not the building blocks of DNA; they are a type of lipid molecule.

2. In the reaction 2H2 + O2 → 2H2O, how many moles of oxygen are required to react completely with 4 moles of hydrogen?

• A. 1
• B. 2
• C. 3
• D. 4

Correct answer: B

Rationale: The balanced chemical equation indicates that 2 moles of H2 react with 1 mole of O2 to produce 2 moles of H2O. To determine how many moles of O2 are required to react with 4 moles of H2, you can use the mole ratio from the balanced equation: 2 moles of H2 react with 1 mole of O2. Therefore, to react completely with 4 moles of H2, you would need 2 moles of O2 (4 moles H2 ÷ 2 moles H2 per 1 mole O2). Hence, 2 moles of oxygen are required to react completely with 4 moles of hydrogen. Choices A, C, and D are incorrect because they do not reflect the correct stoichiometry as defined by the balanced chemical equation.

3. How does urine flow through the urethra?

• A. Continuously
• B. Only when the bladder is completely full
• C. Under voluntary control of sphincter muscles
• D. A combination of B and C

Correct answer: C

Rationale: Urine flows through the urethra under voluntary control of sphincter muscles. These muscles can be consciously contracted or relaxed to control the flow of urine from the bladder to the outside of the body. Choice A is incorrect as urine flow is not continuous but rather regulated. Choice B is incorrect because urine flow is not restricted to only when the bladder is completely full. Choice D is incorrect as it inaccurately combines the two incorrect statements of choices B and C.

4. The Becquerel (Bq) is the designated unit for quantifying:

• A. Electron volt (eV) measurements of energy
• B. Radioactivity
• C. Electric charge (Coulombs)
• D. Force (Newtons)

Correct answer: B

Rationale: The Becquerel (Bq) is the unit used to measure radioactivity, specifically the activity of a quantity of radioactive material. It represents the number of radioactive disintegrations or transformations per unit of time. Choice A, electron volt (eV), is a unit of energy, not radioactivity. Choice C, electric charge (Coulombs), is measured in Coulombs, not Becquerels. Choice D, force (Newtons), is a unit of force, not radioactivity. Therefore, the correct answer is B.

5. Which part of the digestive system is responsible for absorbing nutrients?

• A. Esophagus
• B. Stomach
• C. Small intestine
• D. Large intestine

Correct answer: C

Rationale: The small intestine is the correct answer because it is the primary site for nutrient absorption in the digestive system. It contains specialized structures such as villi and microvilli that maximize the absorption of nutrients from digested food. The esophagus is responsible for transporting food from the mouth to the stomach; the stomach primarily aids in digestion by secreting enzymes and acids; and the large intestine mainly absorbs water and electrolytes from the remaining indigestible food matter. Therefore, the small intestine plays a crucial role in absorbing essential nutrients for the body's functions, making it the correct choice in this context.

Similar Questions