Nursing Elites

1. What is the role of RNA interference in silencing genes?

• A. Increases protein production
• B. Promotes gene mutation
• C. Inhibits the expression of specific genes
• D. Repairs damaged DNA

Correct answer: C

Rationale: Rationale: RNA interference (RNAi) is a biological process that involves the silencing of gene expression by inhibiting the translation of mRNA or by degrading mRNA molecules. This mechanism plays a crucial role in regulating gene expression and can be used to selectively silence specific genes. By interfering with the expression of specific genes, RNAi can downregulate protein production from those genes. Therefore, option C, "Inhibits the expression of specific genes," is the correct role of RNA interference in silencing genes.

2. What is the oxidation state of carbon in CH4?

• A. +1
• B. -1
• C. +2
• D. -4

Correct answer: d

Rationale: Each hydrogen atom has an oxidation state of +1, and the sum of oxidation states in CH4 is 0. Therefore, carbon has an oxidation state of -4.

3. Where does bile, a substance that helps digest fats, come from?

• A. Stomach
• B. Pancreas
• C. Liver
• D. Gallbladder

Correct answer: C

Rationale: Rationale: Bile is a substance that helps digest fats by emulsifying them, which means breaking down large fat globules into smaller droplets to increase the efficiency of fat digestion by enzymes. The liver produces bile, which is then stored and concentrated in the gallbladder before being released into the small intestine to aid in the digestion and absorption of fats. The stomach (option A) is responsible for the initial digestion of food through the action of gastric juices, but bile is not produced in the stomach. The pancreas (option B) secretes digestive enzymes such as lipase to further break down fats in the small intestine, but it does not produce bile. The gallbladder (option D) stores and concentrates bile produced by the liver but does not actually produce bile itself.

4. What is the term for a solution that has exactly the same concentration of solute as another solution?

• A. Saturated solution
• B. Unsaturated solution
• C. Isotonic solution
• D. Concentrated solution

Correct answer: c

Rationale: An isotonic solution has the same concentration of solute as another solution. The other choices do not accurately describe an isotonic solution.

5. 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 designated unit for quantifying radioactivity. Radioactivity is the measure of the rate at which radioactive atoms undergo nuclear decay and emit radiation. One Becquerel is equal to one nuclear decay event per second. This unit is named after Henri Becquerel, the scientist who discovered radioactivity. Therefore, option B, 'Radioactivity,' is the correct answer. Electron volt (eV) measurements of energy are quantified using a different unit, electric charge is measured in Coulombs, and force is quantified in Newtons, making them incorrect choices for this question.

6. The tiny air sacs in the lungs where gas exchange takes place are called:

• A. Bronchi
• B. Trachea
• C. Alveoli
• D. Pleura

Correct answer: A

Rationale: The correct answer is C: 'Alveoli.' Alveoli are the tiny air sacs in the lungs where gas exchange takes place. Oxygen from the air is diffused into the blood, and carbon dioxide from the blood is diffused into the air in the alveoli. Bronchi (option A) are the large air passages that lead from the trachea into the lungs. Trachea (option B) is the windpipe that connects the larynx to the bronchi. Pleura (option D) is a thin membrane that surrounds the lungs and lines the chest cavity. Understanding these structures is essential for comprehending respiratory function and gas exchange in the human body.

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