Nursing Elites

1. What is the name of the regulatory region in a gene that controls its expression?

• A. Exon
• B. Intron
• C. Promoter
• D. Enhancer

Correct answer: C

Rationale: Rationale: A) Exon: Exons are the coding regions of a gene that are transcribed into mRNA and eventually translated into proteins. Exons do not regulate gene expression. B) Intron: Introns are non-coding regions of a gene that are removed during RNA processing and do not play a direct role in controlling gene expression. C) Promoter: The promoter is a regulatory region located at the beginning of a gene that initiates the process of transcription by binding transcription factors and RNA polymerase. It plays a crucial role in controlling gene expression. D) Enhancer: Enhancers are regulatory regions that can be located far from the gene they regulate and can increase the transcription of a gene. While enhancers are important for gene expression, the specific region that controls gene expression is the promoter. Therefore, the correct answer is C) Promoter, as it is the regulatory region in a gene that controls its expression by initiating transcription.

2. How many amino acids can make up a protein?

• A. 10-20
• B. 50-100
• C. 100-500
• D. 1000+

Correct answer: A

Rationale: Rationale: Proteins are made up of long chains of amino acids. There are 20 standard amino acids that are commonly found in proteins. The sequence and arrangement of these amino acids determine the structure and function of a protein. While proteins can vary in size and complexity, the number of amino acids typically ranges from around 10 to 20 in smaller proteins to hundreds or even thousands in larger proteins. Therefore, the range of 10-20 amino acids is the most accurate representation of the number of amino acids that can make up a protein.

3. Which skin condition is characterized by patches of inflamed, reddened skin and is often triggered by allergens or stress?

• A. Eczema
• B. Psoriasis
• C. Acne
• D. Vitiligo

Correct answer: A

Rationale: The correct answer is A: Eczema. Eczema is a skin condition characterized by patches of inflamed, reddened skin that can be triggered by allergens or stress. It is a chronic condition that can cause itching and discomfort. Psoriasis (option B) is a different skin condition characterized by red, scaly patches on the skin. Acne (option C) is a common skin condition characterized by pimples and clogged pores. Vitiligo (option D) is a condition where the skin loses its pigment, resulting in white patches. Therefore, eczema best fits the description provided in the question.

4. What is the valve that prevents blood from flowing back from the left ventricle into the left atrium?

• A. Tricuspid valve
• B. Mitral valve
• C. Aortic valve
• D. Pulmonic valve

Correct answer: B

Rationale: The correct answer is B: Mitral valve. The mitral valve, also known as the bicuspid valve, is located between the left atrium and the left ventricle. Its primary function is to prevent the backflow of blood from the left ventricle into the left atrium during ventricular contraction. The tricuspid valve is located between the right atrium and right ventricle, the aortic valve is located between the left ventricle and the aorta, and the pulmonic valve is located between the right ventricle and the pulmonary artery. Therefore, the mitral valve is specifically responsible for preventing backflow in the left side of the heart, making it the correct answer.

5. Chyle, a milky white fluid, is transported by lymphatic vessels from the:

• A. Lungs
• B. Intestines
• C. Kidneys
• D. Skin

Correct answer: B

Rationale: The correct answer is B: Intestines. Chyle is a milky white fluid that is formed in the small intestine during digestion, mainly from the absorption of dietary fats. It is rich in fats and lymphocytes. Lymphatic vessels in the intestines, called lacteals, absorb the chyle and transport it through the lymphatic system. Chyle eventually enters the bloodstream via the thoracic duct. The lungs are responsible for gas exchange, not the transport of chyle. The kidneys are involved in filtering blood and producing urine. The skin is the body's largest organ responsible for protection, temperature regulation, and sensation, but it is not involved in transporting chyle.

6. Which vitamin is crucial for calcium absorption and synthesized in the skin upon sun exposure?

• A. Vitamin A
• B. Vitamin C
• C. Vitamin D
• D. Vitamin E

Correct answer: C

Rationale: The correct answer is C: Vitamin D. Vitamin D is crucial for calcium absorption as it helps the body absorb calcium from the diet. When the skin is exposed to sunlight, it produces vitamin D. This is why sunlight is often referred to as the 'sunshine vitamin.' Vitamin A (choice A) is important for vision and immune function, but not specifically for calcium absorption. Vitamin C (choice B) is essential for collagen production and immune function, but not directly related to calcium absorption. Vitamin E (choice D) is an antioxidant that helps protect cells from damage, but it is not primarily involved in calcium absorption like vitamin D.

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