Nursing Elites

1. Which names a final step in protein synthesis?

• A. DNA unzips.
• B. Amino acids bond.
• C. Transfer RNA bonds to messenger RNA.
• D. Messenger RNA moves to ribosomes.

Correct answer: B

Rationale: The final step in protein synthesis is when amino acids bond together to form a protein chain. This process occurs during translation, where transfer RNA (tRNA) brings specific amino acids to the ribosome, and the ribosome catalyzes the formation of peptide bonds between the amino acids. This step ultimately leads to the synthesis of a complete protein based on the instructions from messenger RNA (mRNA). Choice A ('DNA unzips') is incorrect as it refers to the initiation of transcription, not the final step of protein synthesis. Choice C ('Transfer RNA bonds to messenger RNA') is incorrect as it describes the process of translation initiation rather than the final step. Choice D ('Messenger RNA moves to ribosomes') is also incorrect as mRNA is already present at the ribosomes throughout the translation process, not just in the final step.

2. Where is the ovary located in a flowering plant?

• A. Anther
• B. Pistil
• C. Stamen
• D. Calyx

Correct answer: B

Rationale: The ovary is located in the pistil of a flowering plant. The pistil is the female reproductive part of the flower, and it consists of the ovary, style, and stigma. The ovary contains ovules, which develop into seeds after fertilization. Choice A, 'Anther,' is incorrect because the anther is the part of the flower's stamen that produces pollen. Choice C, 'Stamen,' is incorrect because the stamen is the male reproductive part of the flower, consisting of the anther and filament. Choice D, 'Calyx,' is incorrect because the calyx is the outermost whorl of a flower, composed of sepals that protect the flower bud.

3. In an example of a male with hemophilia and a female carrier, what percentage of the offspring is predicted to be carriers only?

• A. 0%
• B. 25%
• C. 50%
• D. 100%

Correct answer: C

Rationale: In this scenario, the male offspring will inherit the X chromosome with the hemophilia gene from the mother, as males have one X chromosome inherited from their mother. The female offspring will inherit one normal X chromosome from the father and one X chromosome with the hemophilia gene from the mother, making them carriers of the hemophilia trait. Therefore, 50% of the offspring will be carriers only. Option A (0%) is incorrect as female offspring will inherit the X chromosome with the hemophilia gene from the mother. Option B (25%) is incorrect as the female offspring will not be unaffected. Option D (100%) is incorrect as not all offspring will be carriers, only the female offspring.

4. What is the role of tRNA during protein synthesis?

• A. Carries amino acids to the ribosome
• B. Links nucleotides together
• C. Copies DNA sequences
• D. Replicates genetic material

Correct answer: A

Rationale: During protein synthesis, tRNA plays the crucial role of carrying amino acids to the ribosome. This process ensures that the correct amino acids are brought to the ribosome according to the mRNA sequence. Choice B, linking nucleotides together, refers to the role of RNA polymerase in transcription, not tRNA. Choice C, copying DNA sequences, is the function of DNA polymerase during DNA replication, while choice D, replicating genetic material, is an overarching function of DNA replication, not specific to tRNA's role in protein synthesis.

5. Select the cell parts that are present in plant cells but not animal cells (there may be more than one answer):

• A. Cell membrane
• B. Cell wall
• C. Ribosome
• D. Chloroplast

Correct answer: B

Rationale: Plant cells have a cell wall (B) which provides structural support and protection for the cell, a feature that is not present in animal cells. The cell membrane (A) is found in both plant and animal cells. Ribosomes (C) are present in both types of cells and are responsible for protein synthesis. Chloroplasts (D) are unique to plant cells and are responsible for carrying out photosynthesis. Therefore, the correct answers are B and D because the cell wall and chloroplast are specific to plant cells, while the cell membrane and ribosomes are found in both plant and animal cells.

Similar Questions