Nursing Elites

1. Which of the following is directly transcribed from DNA and represents the first step in protein synthesis?

• A. siRNA
• B. rRNA
• C. mRNA
• D. tRNA

Correct answer: C

Rationale: mRNA (messenger RNA) is directly transcribed from DNA in the nucleus during the process of transcription. It serves as a template for protein synthesis during translation in the cytoplasm. mRNA carries genetic information from the DNA to the ribosomes, where it determines the sequence of amino acids in a protein. Thus, mRNA represents the first step in protein synthesis as it carries the code from the DNA to be translated into a protein. Choice A, siRNA (small interfering RNA), is involved in post-transcriptional gene silencing and does not play a role in protein synthesis. Choice B, rRNA (ribosomal RNA), is a component of the ribosome and plays a structural and functional role in protein synthesis but is not directly transcribed from DNA. Choice D, tRNA (transfer RNA), is responsible for bringing amino acids to the ribosome during protein synthesis but is not directly transcribed from DNA.

2. Which of the following is NOT a function of the forebrain?

• A. To regulate blood pressure and heart rate
• B. To perceive and interpret emotional responses like fear and anger
• C. To perceive and interpret visual input from the eyes
• D. To integrate voluntary movement

Correct answer: A

Rationale: The correct answer is A. The forebrain is primarily responsible for higher cognitive functions such as perception, interpretation, and integration of sensory information, emotional responses, and voluntary movements. Functions like regulating blood pressure and heart rate are mainly controlled by various structures in the brainstem, such as the medulla oblongata and the pons. Choices B, C, and D are all functions associated with the forebrain. Choice B relates to the limbic system, which is part of the forebrain responsible for emotional responses. Choice C corresponds to the occipital lobe in the forebrain, involved in processing visual information. Choice D involves the motor cortex and other areas in the forebrain that coordinate voluntary movements.

3. Which enzyme found in saliva is responsible for breaking down carbohydrates into smaller molecules like sugars?

• A. Pepsin
• B. Amylase
• C. Lipase
• D. Trypsin

Correct answer: B

Rationale: The correct answer is B. Saliva contains an enzyme called amylase, which specifically targets carbohydrates and breaks them down into smaller molecules like sugars. Pepsin, choice A, is an enzyme found in the stomach that breaks down proteins, not carbohydrates. Lipase, choice C, is responsible for breaking down fats, not carbohydrates. Trypsin, choice D, is an enzyme that breaks down proteins in the small intestine, not carbohydrates. Therefore, choices A, C, and D are incorrect for this question.

4. Alpha waves, characteristic of quiet wakefulness and relaxation, have a frequency range of:

• A. 0.5-4 Hz
• B. 4-8 Hz
• C. 8-13 Hz
• D. 13-30 Hz

Correct answer: C

Rationale: Alpha waves are neural oscillations in the frequency range of 8-13 Hz, which are typically associated with a state of quiet wakefulness and relaxation. Option C, 8-13 Hz, is the correct frequency range for alpha waves. Choices A, B, and D are incorrect as they do not fall within the specific frequency range characteristic of alpha waves.

5. Which of the following substances has an acidic pH?

• A. Lemon juice
• B. Blood
• C. Urine
• D. Salt water

Correct answer: A

Rationale: The correct answer is A, Lemon juice, which has an acidic pH typically around 2 due to its citric acid content. Blood, urine, and salt water are not typically acidic in nature. Blood has a slightly basic pH, urine can vary but is usually slightly acidic to neutral, and salt water is neutral to slightly alkaline. Lemon juice is a commonly known acidic substance, often used in cooking and cleaning due to its acidic properties.

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