Nursing Elites

1. Epithelial cells are:

• A. Polarized
• B. Neutral
• C. Larger than other cells
• D. None of the above

Correct answer: A

Rationale: Epithelial cells have a distinct top (apical) and bottom (basal) side, demonstrating polarity. This polarity is essential for their specialized functions, such as secretion, absorption, and barrier formation. Choice B, 'Neutral,' is incorrect as epithelial cells exhibit polarity. Choice C, 'Larger than other cells,' is incorrect as epithelial cells come in various sizes and are not specifically larger than other cell types. Choice D, 'None of the above,' is incorrect as epithelial cells are indeed polarized.

2. A cell that does not contain membrane-bound organelles or a defined nucleus would be classified as:

• A. eukaryotic
• B. embryonic
• C. prokaryotic
• D. symbiotic

Correct answer: C

Rationale: A cell that does not contain membrane-bound organelles or a defined nucleus is classified as prokaryotic. Prokaryotic cells lack a true nucleus, and their genetic material is typically found in a region called the nucleoid. Examples of prokaryotic organisms include bacteria and archaea. Eukaryotic cells, on the other hand, contain membrane-bound organelles and a true nucleus, distinguishing them from prokaryotic cells. Embryonic and symbiotic classifications are not directly related to the presence of organelles or a nucleus in cells.

3. Where is DNA stored?

• A. The nucleus
• B. Ribosomes
• C. Endoplasmic reticulum
• D. Mitochondria

Correct answer: A

Rationale: DNA is stored in the nucleus of a cell. The nucleus houses the cell's genetic material, including the DNA, which contains the instructions for building and operating the cell. The nucleus controls the activities of the cell and is essential for proper cell function and reproduction. Ribosomes are responsible for protein synthesis, not DNA storage. The endoplasmic reticulum is involved in protein and lipid synthesis, storage, and transport but does not store DNA. Mitochondria are known as the powerhouse of the cell, producing energy in the form of ATP, but they do not store DNA.

4. Which statement is untrue?

• A. RNA is single-stranded.
• B. RNA contains uracil.
• C. DNA codes for proteins.
• D. DNA cannot be altered.

Correct answer: D

Rationale: DNA can be altered through various processes such as mutations, genetic engineering, and epigenetic modifications. Changes in DNA can occur naturally or through external influences, leading to variations in the genetic code. Therefore, the statement that DNA cannot be altered is untrue. Choices A, B, and C are true statements. RNA is indeed single-stranded, RNA contains uracil instead of thymine, and DNA serves as a template for protein synthesis.

5. Where is the site of cellular respiration in eukaryotic cells?

• A. Nucleus
• B. Chloroplasts
• C. Mitochondria
• D. Ribosomes

Correct answer: C

Rationale: The correct answer is C: Mitochondria. Mitochondria are often referred to as the powerhouse of the cell because they are responsible for cellular respiration in eukaryotic cells. During cellular respiration, mitochondria generate energy in the form of ATP. Choices A, B, and D are incorrect. The nucleus is the organelle that houses the cell's genetic material, chloroplasts are responsible for photosynthesis in plant cells, and ribosomes are involved in protein synthesis, not cellular respiration.

Similar Questions