Finals Practice Test
## Section 1: Multiple-Choice Questions (MCQs)
1. Who used the swan-neck flask to demonstrate that air contains microbes, which debunked the theory of spontaneous generation?
- A) Francesco Redi
- B) Louis Pasteur
- C) John Tyndall
- D) Robert Hooke
2. Which of the following cell types is responsible for the production of antibodies?
- A) Macrophages
- B) B cells
- C) Helper T cells
- D) Cytotoxic T cells
3. The term "biogenesis" refers to:
- A) The hypothesis that life arises from non-living matter.
- B) The theory that living organisms arise from other living organisms.
- C) The process of developing a vaccine.
- D) A classification system for microorganisms.
4. What is a characteristic of Gram-positive bacteria?
- A) Thin cell wall with an outer membrane
- B) Thick peptidoglycan cell wall
- C) High resistance to antibiotics due to outer membrane
- D) Low susceptibility to detergents
5. Which of the following components is present in eukaryotic cells but not in prokaryotic cells?
- A) Ribosomes
- B) Nucleus
- C) Cell membrane
- D) DNA
6. Which of the following is a correct characteristic of viruses?
- A) They are living organisms with complex cellular structures.
- B) They contain either DNA or RNA as their genetic material.
- C) They can replicate independently without a host cell.
- D) They are considered eukaryotic microorganisms.
7. The lag phase in a bacterial growth curve represents:
- A) A period of adaptation to new conditions.
- B) Rapid cell division and exponential growth.
- C) A period where cell division equals cell death.
- D) A period of rapid cell death due to nutrient depletion.
8. What is the primary function of natural killer cells?
- A) To produce antibodies against pathogens.
- B) To induce apoptosis in virus-infected cells.
- C) To help activate B cells and cytotoxic T cells.
- D) To phagocytose bacteria and dead cells.
9. Which of the following is a method of microbial control that results in the destruction of all microbial life, including spores and viruses?
- A) Pasteurization
- B) Disinfection
- C) Sterilization
- D) Antisepsis
10. Which of the following is a common method used to differentiate between different types of prokaryotic cells based on cell wall structure?
- A) Gram staining
- B) Electron microscopy
- C) Polymerase Chain Reaction (PCR)
- D) Protein sequencing
11. What is the main outcome of an inflammatory response?
- A) Activation of the adaptive immune response
- B) Recruitment of immune cells to the site of injury or infection
- C) Formation of memory cells for long-term immunity
- D) Production of antibodies to neutralize pathogens
12. Which of the following is a key difference between the lytic cycle and the lysogenic cycle in bacteriophages?
- A) The lytic cycle leads to cell lysis and release of new phages, while the lysogenic cycle integrates phage DNA into the host genome.
- B) The lysogenic cycle occurs in eukaryotic cells, while the lytic cycle occurs in prokaryotic cells.
- C) The lytic cycle involves prophages, while the lysogenic cycle involves mature viruses.
- D) The lysogenic cycle is associated with rapid viral replication, while the lytic cycle is slower.
13. Which of the following terms best describes the process where viral spikes or glycoproteins interact with specific receptors on the host cell?
- A) Attachment
- B) Penetration
- C) Replication
- D) Assembly
14. What is the importance of the innate immune system's normal microbiota in human health?
- A) It directly fights off viral infections.
- B) It competes with pathogens for resources and space.
- C) It triggers specific immune responses against antigens.
- D) It is responsible for developing immune memory.
15. Which of the following best describes the term "herd immunity"?
- A) A situation where a high proportion of a population is immune, reducing the spread of infection.
- B) A phenomenon where all individuals in a population are immune due to prior infection.
- C) A method of producing immunity by introducing a weakened form of a pathogen.
- D) A strategy to boost immunity by administering antibodies directly.
16. What is a key benefit of using attenuated (live) vaccines over inactivated (dead) vaccines?
- A) Attenuated vaccines are safer for immunocompromised individuals.
- B) Attenuated vaccines generally produce a stronger and longer-lasting immune response.
- C) Attenuated vaccines require more doses to be effective.
- D) Attenuated vaccines contain only parts of the pathogen.
## Section 2: True or False Questions
17. Conjugation is a method of horizontal gene transfer where bacteria transfer genetic material through direct cell-to-cell contact. (True/False)
18. The membrane attack complex (MAC) is formed during the complement cascade and leads to lysis of microbial cells. (True/False)
19. The endospore is a resistant structure formed by some bacteria to survive in harsh conditions. (True/False)
20. Antigenic variation allows some pathogens to evade immune detection by changing their surface antigens. (True/False)
21. T cells are derived from myeloid progenitor cells in the bone marrow. (True/False)
22. Joseph Lister's antiseptic surgery techniques significantly reduced post-operative infections by using carbolic acid to disinfect surgical instruments and wounds. (True/False)
23. The RNA-dependent RNA polymerase is an enzyme required by retroviruses to convert RNA into DNA. (True/False)
24. A nosocomial infection is one acquired in a healthcare setting. (True/False)
25. Phylogeny is the evolutionary history and relationships among organisms, often depicted in a phylogenetic tree. (True/False)
## Section 3: Fill in the Blanks
26. ________________ is the outer protective structure of a bacterium that helps prevent phagocytosis and desiccation.
27. The 16S rRNA gene is commonly used for ________________ analysis and classification of prokaryotic organisms.
28. ________________ is the primary energy source for photoautotrophs, which use it to convert carbon dioxide into organic compounds.
29. ________________ is the time between pathogen exposure and the onset of symptoms.
30. ________________ are small circular pieces of DNA in prokaryotic cells that can carry extra genes, including antibiotic resistance genes.
31. The ________________ method uses a disk diffusion technique to determine the sensitivity of bacteria to different antibiotics.
32. ________________ is a eukaryotic organelle responsible for energy production and contains its own DNA.
33. ________________ is a term used to describe a disease that is consistently present within a specific region or population.
34. ________________ is the measurement used to determine the lowest concentration of an antibiotic that inhibits bacterial growth.
35. ________________ is a type of helminth with a segmented body, commonly known as a tapeworm.
## Section 4: Short Answer Questions
36. Describe the steps involved in the Gram staining technique and explain how it differentiates between Gram-positive and Gram-negative bacteria.
37. Explain the significance of Koch's postulates in establishing a causal relationship between a pathogen and a disease. What are the limitations of these postulates?
38. Outline the mechanisms by which bacteria can acquire antibiotic resistance. Name at least two examples of resistance mechanisms.
39. What are the key differences between innate immunity and adaptive immunity in terms of specificity and response time? Provide examples of cells involved in each type of immunity.
40. Describe the role of antigen-presenting cells (APCs) in the adaptive immune response. What is their importance in activating T cells?
41. Explain the structure of a typical virus. What are the key components of viruses, and how do they contribute to viral replication and host infection?
## Section 5: Essay Questions
42. Discuss the concept of horizontal gene transfer in bacteria. Describe the three primary methods by which bacteria can transfer genetic material and explain how this contributes to genetic diversity and the spread of antibiotic resistance.
43. Describe the process of phagocytosis in the innate immune system. What are the key steps involved, and what mechanisms do phagocytic cells use to destroy pathogens?
44. Outline the lifecycle of a typical virus that infects eukaryotic cells. Discuss the steps involved from attachment to release and explain how these steps differ depending on whether the virus is naked or enveloped.
45. Discuss the role of public health organizations in monitoring and controlling infectious diseases. What are the common methods used to track disease outbreaks, and how do these organizations contribute to preventing pandemics?
Final exam essay prompts SP 2024:
1. Cell wall comparisons: Compare/contrast structures of Gram positive vs. Gram negative cell wall
2. Describe differences between eukaryotic and prokaryotic cells
3. List the key concepts associated with light microscopy.
Outline the phases of the standard bacterial growth curve observed in any closed system
5 What is the difference between sterilization and disinfection/decontamination?
6. Streptomycin (an antibiotic) binds to the small ribosomal subunit of bacteria (but not to the ribosomes of the host cells infected by bacteria). The result is the misreading of bacterial mRNA. What process is being affected, and explain how this kills bacterial cells?
7. Describe three mechanisms of horizontal gene transfer in prokaryotes