Nursing Elites

1. What are plasma membranes mostly made of?

• A. Proteins
• B. Carbohydrates
• C. Lipids
• D. Nucleotides

Correct answer: C

Rationale: The correct answer is C: Lipids. Plasma membranes are primarily composed of lipids, specifically phospholipids, which form a lipid bilayer. While proteins are also an essential component of plasma membranes, they are not the primary constituent. Carbohydrates are present on the outer surface of the membrane but are not the main structural component. Nucleotides are the building blocks of nucleic acids like DNA and RNA and are not the main constituents of plasma membranes.

2. 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.

3. In contrast with triglycerides, phospholipids are lacking one of which of the following components?

• A. Monosaccharide
• B. Glycerol
• C. Phosphates
• D. Fatty acid

Correct answer: B

Rationale: Phospholipids are structurally similar to triglycerides but lack one of the fatty acid chains that triglycerides possess. Triglycerides consist of three fatty acid chains attached to a glycerol molecule, while phospholipids have two fatty acid chains and a phosphate group attached to a glycerol backbone. Therefore, phospholipids are lacking the third fatty acid chain found in triglycerides. Choice A (Monosaccharide) is incorrect because neither triglycerides nor phospholipids contain monosaccharides in their structure. Choice C (Phosphates) is incorrect because phospholipids actually contain phosphates, unlike triglycerides. Choice D (Fatty acid) is incorrect as both triglycerides and phospholipids contain fatty acids, but the number of fatty acid chains differs between the two.

4. What type of cells possess a cell membrane?

• A. Prokaryotic cells only
• B. Eukaryotic cells only
• C. Both prokaryotic and eukaryotic cells
• D. None of the above

Correct answer: C

Rationale: Cell membranes are present in both prokaryotic and eukaryotic cells. The cell membrane serves as a barrier that encloses the cell contents and regulates the entry and exit of substances in and out of the cell. It is a fundamental structure found in all types of cells, regardless of whether they are prokaryotic (lacking a nucleus) or eukaryotic (containing a nucleus). Choice A is incorrect because eukaryotic cells also possess cell membranes. Choice B is incorrect as prokaryotic cells, such as bacteria, also have cell membranes. Choice D is incorrect as both prokaryotic and eukaryotic cells have cell membranes.

5. What type of cell is an animal cell?

• A. Prokaryotic
• B. Eukaryotic
• C. Plant Cell
• D. Bacterial Cell

Correct answer: B

Rationale: The correct answer is B, eukaryotic. Animal cells are classified as eukaryotic cells because they contain membrane-bound organelles such as the nucleus, mitochondria, and endoplasmic reticulum. Choice A, prokaryotic, is incorrect as prokaryotic cells lack membrane-bound organelles. Choice C, Plant Cell, is incorrect as the question specifically asks about animal cells. Choice D, Bacterial Cell, is incorrect as bacteria are prokaryotic cells.

Similar Questions