Nursing Elites

1. How does an enzyme work on a chemical reaction that occurs in a substrate?

• A. An enzyme slows down the chemical reaction.
• B. An enzyme speeds up the chemical reaction.
• C. An enzyme has no effect on the chemical reaction.
• D. An enzyme stops most chemical reactions.

Correct answer: B

Rationale: Enzymes are biological catalysts that facilitate chemical reactions by lowering the activation energy required for the reaction to occur. This allows the reaction to proceed more quickly and efficiently. Enzymes do not change the overall outcome of the reaction, but they significantly increase the rate at which it takes place. Therefore, choice B, 'An enzyme speeds up the chemical reaction,' is the correct answer. Choices A, C, and D are incorrect because enzymes do not slow down, have no effect, or stop chemical reactions; instead, they accelerate the process by lowering the activation energy.

2. Why does cytokinesis happen?

• A. DNA can duplicate
• B. Organelles can convert energy
• C. Bacteria can be killed
• D. Daughter cells can divide

Correct answer: D

Rationale: Cytokinesis happens at the end of mitosis to physically separate the newly formed daughter cells. This allows the cell to divide into two separate daughter cells, each containing a complete set of genetic material (DNA) and organelles. The purpose of cytokinesis is to ensure that each daughter cell receives the necessary components to function independently. Choices A, B, and C are incorrect because cytokinesis does not directly involve DNA duplication, organelles converting energy, or killing bacteria.

3. The renal system consists of all the organs involved in the formation and release of urine and includes the kidneys, ureters, bladder, and urethra.

• A. The digestive system
• B. The reproductive system
• C. The renal system
• D. The kidney system

Correct answer: C

Rationale: The correct term for the system involving the organs responsible for the formation and release of urine is the renal system, not the digestive or reproductive system. The kidneys, ureters, bladder, and urethra are specifically part of the renal system, which is responsible for filtering the blood to remove waste and excess fluids, producing urine, and eliminating it from the body. The other choices, the digestive system and the reproductive system, are not responsible for the formation and release of urine, making them incorrect answers.

4. Which gives the order of four taxonomic categories from least to most specific?

• A. Kingdom, phylum, class, order
• B. Kingdom, phylum, order, class
• C. Kingdom, order, phylum, class
• D. Kingdom, class, order, phylum

Correct answer: A

Rationale: The correct order of the four taxonomic categories from least to most specific is Kingdom, phylum, class, and order. This sequence adheres to the hierarchical system of classification where organisms are grouped based on shared characteristics, becoming more specific as you move from Kingdom to order. Choice B is incorrect as the order of 'order' and 'class' is swapped. Choice C is incorrect as 'order' precedes 'phylum' instead of following it. Choice D is incorrect as 'class' should come before 'order'.

5. Which cellular structure is largely protective in function?

• A. Mitochondrion
• B. Vacuole
• C. Cell membrane
• D. Ribosome

Correct answer: C

Rationale: The correct answer is C: Cell membrane. The cell membrane, also known as the plasma membrane, is largely protective in function as it serves as a selectively permeable barrier that surrounds the cell, providing structural support and helping to maintain cell integrity. It regulates the movement of substances in and out of the cell, thus protecting the cell from harmful external factors while allowing essential nutrients to enter. Mitochondrion (choice A) is responsible for energy production, not primarily protective. Vacuole (choice B) is mainly involved in storage and transport. Ribosome (choice D) is involved in protein synthesis, not protective functions.

Similar Questions