Nursing Elites

1. What is the function of ribosomes?

• A. Packaging and transporting proteins
• B. Storing genetic material
• C. Controlling cell division
• D. Synthesizing proteins

Correct answer: D

Rationale: The correct answer is D: Synthesizing proteins. Ribosomes are cellular organelles responsible for protein synthesis. They read the messenger RNA (mRNA) and utilize the information to assemble amino acids into proteins through a process known as translation. Choice A, packaging and transporting proteins, is incorrect as this function is typically performed by the Golgi apparatus and vesicles. Choice B, storing genetic material, is incorrect as genetic material is usually stored in the nucleus in the form of DNA. Choice C, controlling cell division, is incorrect as this function is primarily regulated by the cell cycle checkpoints and specific proteins involved in cell cycle regulation.

2. Which of the following is NOT a source of genetic variation in a population?

• A. Mutations in genes
• B. Genetic drift (random fluctuations in allele frequencies)
• C. Gene flow (movement of genes between populations)
• D. Blending inheritance (traits of parents are averaged in offspring)

Correct answer: D

Rationale: Rationale: A) Mutations in genes: Mutations are changes in the DNA sequence that can introduce new alleles into a population, leading to genetic variation. B) Genetic drift (random fluctuations in allele frequencies): Genetic drift refers to random changes in allele frequencies in a population, which can lead to genetic variation through chance events. C) Gene flow (movement of genes between populations): Gene flow occurs when individuals move between populations, bringing new alleles with them and increasing genetic variation within populations. D) Blending inheritance (traits of parents are averaged in offspring): Blending inheritance was a historical theory that suggested offspring inherit a blend of traits from their parents, leading to a reduction in genetic variation over time. However, this concept has been disproven by the understanding of Mendelian genetics, where traits are inherited independently and do not blend together. Therefore, blending inheritance does not contribute

3. What type of genetic variation is caused by changes in the DNA sequence?

• A. Epigenetic variation
• B. Phenotypic variation
• C. Genotypic variation
• D. Behavioral variation

Correct answer: C

Rationale: A) Epigenetic variation refers to changes in gene expression that do not involve alterations in the DNA sequence itself. These changes can be influenced by environmental factors. B) Phenotypic variation refers to differences in observable traits or characteristics of an organism, which can be influenced by both genetic and environmental factors. C) Genotypic variation is caused by changes in the DNA sequence, such as mutations or genetic recombination. These changes directly impact the genetic information carried by an organism. D) Behavioral variation refers to differences in behavior among individuals of the same species, which can be influenced by genetic, environmental, and experiential factors.

4. Mesosomes are the internal extensions of which of the following?

• A. Capsule
• B. Cell membranes
• C. Cell wall
• D. Chromatin body

Correct answer: B

Rationale: Mesosomes are the internal extensions of the cell membrane, not the capsule, cell wall, or chromatin body. They play a crucial role in cell division and are essential for various cellular processes such as respiration and cell wall formation. Mesosomes are not associated with the capsule (choice A), cell wall (choice C), or chromatin body (choice D), making these options incorrect.

5. Which of the following best describes eosinophils?

• A. A type of granulocyte that secretes histamine to stimulate the inflammatory response.
• B. The most abundant type of white blood cell that secretes substances toxic to pathogens.
• C. A type of granulocyte found under mucous membranes that defends against multicellular parasites.
• D. A circulating granulocyte with high phagocytic activity and aggressiveness.

Correct answer: C

Rationale: Eosinophils are best described as a type of granulocyte found under mucous membranes that defends against multicellular parasites. They release toxic substances to combat parasitic infections and play a significant role in allergic reactions and asthma. Histamine secretion to stimulate inflammation is more characteristic of basophils, while high phagocytic activity and aggressiveness are features of neutrophils, not eosinophils. Describing eosinophils as the most abundant type of white blood cell that secretes toxic substances to pathogens is inaccurate since eosinophils specifically target multicellular parasites, not a broad range of pathogens.

Similar Questions