Nursing Elites

1. Which organelle is responsible for the synthesis of lipids and steroid hormones?

• A. Rough endoplasmic reticulum
• B. Smooth endoplasmic reticulum
• C. Golgi apparatus
• D. Ribosomes

Correct answer: B

Rationale: The smooth endoplasmic reticulum is the correct organelle responsible for the synthesis of lipids, including phospholipids, cholesterol, and steroid hormones. The rough endoplasmic reticulum is primarily involved in protein synthesis and processing, making choice A incorrect. The Golgi apparatus is responsible for modifying, sorting, and packaging proteins and lipids for transportation, so it is not directly involved in lipid and steroid hormone synthesis, making choice C incorrect. Ribosomes are responsible for protein synthesis and are not involved in lipid or steroid hormone synthesis, making choice D incorrect.

2. Prophase is the first stage of mitosis. Which of the following best describes chromosomes during this stage?

• A. They are gathered on either side of the separating cell
• B. They are all aligned along the metaphase plate
• C. They are attached to the spindle
• D. They are visibly separate

Correct answer: D

Rationale: The correct answer is D. During prophase, the chromosomes condense and become visible as distinct structures under a microscope. Choice A is incorrect as chromosomes are not gathered on either side of the separating cell during prophase. Choice B is incorrect because chromosomes align along the metaphase plate during the subsequent stage, metaphase. Choice C is incorrect as chromosomes become attached to the spindle fibers during prometaphase, the stage following prophase.

3. The term pleiotropy is best defined as which of the following?

• A. A situation in which one gene remains unexpressed
• B. One gene influencing multiple, seemingly unrelated phenotypic traits
• C. Two genes affected by a single allele
• D. A condition in which multiple genes are missing

Correct answer: B

Rationale: Pleiotropy is best defined as one gene influencing multiple, seemingly unrelated phenotypic traits. This phenomenon showcases the multifunctionality of genes, where a single gene can have effects on various aspects of an organism's phenotype. Choices A, C, and D do not accurately capture the concept of pleiotropy. Option A refers to gene expression, not pleiotropy. Option C describes genetic interactions but not in the context of pleiotropy. Option D talks about missing genes, which is unrelated to the definition of pleiotropy.

4. Which of the following is the process that reduces cells originally classified as diploid to haploid?

• A. Meiosis
• B. Photosynthesis
• C. Mitosis
• D. Cytokinesis

Correct answer: A

Rationale: The correct answer is A, Meiosis. Meiosis is the cell division process that reduces the chromosome number from diploid to haploid, which is essential for sexual reproduction. Choice B, Photosynthesis, is the process by which green plants and some other organisms use sunlight to synthesize foods with the help of chlorophyll. Choice C, Mitosis, is a cell division process that results in two diploid daughter cells with the same number of chromosomes as the parent cell. Choice D, Cytokinesis, is the division of the cytoplasm following cell division.

5. Protein synthesis begins with a process known as transcription. Where does this process occur?

• A. In the cytoplasm
• B. In the nuclear envelope
• C. In the ribosome unit
• D. In the nucleus

Correct answer: D

Rationale: The correct answer is D: In the nucleus. Transcription, the initial step of protein synthesis, takes place in the nucleus where DNA is transcribed into mRNA. This mRNA then leaves the nucleus and enters the cytoplasm where translation occurs on the ribosomes. Choices A, B, and C are incorrect because transcription specifically occurs in the nucleus, not in the cytoplasm, nuclear envelope, or ribosome unit.

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