Nursing Elites

1. What is a reaction between an acid and a base known as?

• A. Precipitation
• B. Neutralization
• C. Oxidation-reduction
• D. Photolysis

Correct answer: B

Rationale: The correct answer is B: Neutralization. When an acid and a base react, they neutralize each other's properties, resulting in the formation of water and a salt. Choice A, 'Precipitation,' refers to the formation of a solid from a solution during a chemical reaction. Choice C, 'Oxidation-reduction,' involves the transfer of electrons between reactants. Choice D, 'Photolysis,' is a reaction where a compound is broken down into smaller components by light energy. Therefore, the most appropriate term for a reaction between an acid and a base is neutralization.

2. During embryonic development, all tissues originate from

• A. Epithelial tissue only
• B. Muscle tissue only
• C. Connective tissue only
• D. Embryonic germ layers

Correct answer: D

Rationale: During embryonic development, all tissues originate from the three primary germ layers: ectoderm, mesoderm, and endoderm. These germ layers give rise to various tissues and organs in the developing embryo through a process called gastrulation. Epithelial, muscle, and connective tissues are derived from these germ layers during development. Therefore, choices A, B, and C are incorrect as tissues do not originate from a single type of tissue but rather from the embryonic germ layers which differentiate into various tissues and organs.

3. Which hormone is responsible for regulating sleep-wake cycles and is influenced by light exposure?

• A. Melatonin
• B. Cortisol
• C. Estrogen
• D. Glucagon

Correct answer: A

Rationale: The correct answer is A: Melatonin. Melatonin is the hormone responsible for regulating sleep-wake cycles, also known as the circadian rhythm. Its production is influenced by light exposure, with levels increasing in the evening in response to darkness, signaling the body that it is time to sleep. Choice B, cortisol, is a stress hormone and does not directly regulate sleep-wake cycles. Choice C, estrogen, is a sex hormone and is not primarily involved in regulating sleep. Choice D, glucagon, is a hormone that increases blood glucose levels and is not related to sleep-wake cycles.

4. Which of the following enzymes is responsible for adding a nucleotide to a growing DNA chain?

• A. Helicase
• B. Ligase
• C. Nuclease
• D. Polymerase

Correct answer: D

Rationale: The correct answer is Polymerase. Polymerase is the enzyme responsible for adding nucleotides to a growing DNA chain during DNA replication. Helicase unwinds the DNA double helix to separate the DNA strands for replication, Ligase joins DNA fragments together by catalyzing the formation of phosphodiester bonds between them, and Nuclease cuts or degrades DNA strands. Therefore, choices A, B, and C are incorrect in the context of adding nucleotides to a growing DNA chain.

5. How many pairs of chromosomes are in a human cell?

• A. 46
• B. 23
• C. 64
• D. 32

Correct answer: B

Rationale: The correct answer is B: 23. Humans have 23 pairs of chromosomes, totaling 46 chromosomes. Each pair consists of one chromosome inherited from the mother and one from the father, making a total of 46 chromosomes in a human cell. Choice A (46) is incorrect as it represents the total number of chromosomes, not pairs. Choice C (64) and D (32) are incorrect as they do not reflect the accurate number of chromosome pairs in a human cell.

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