Microbiology Questions & Answers PDF

List the 5 major types of microorganisms studied within Microbiology (5marks) \_\_Bacteria\_\_\_ \_\_Viruses\_\_\_ \_\_Fungi\_\_\_\_\_\_\_\_\_ \_\_\_Protozoa / Protists\_\_\_\_ \_\_\_Microalgae\_\_\_\_\_\_\_ 2. List five characteristics that differentiate Eucaryotic Cells from Procaryotic cel...

List the 5 major types of microorganisms studied within Microbiology (5marks) \_\_Bacteria\_\_\_ \_\_Viruses\_\_\_ \_\_Fungi\_\_\_\_\_\_\_\_\_ \_\_\_Protozoa / Protists\_\_\_\_ \_\_\_Microalgae\_\_\_\_\_\_\_ 2. List five characteristics that differentiate Eucaryotic Cells from Procaryotic cells (10marks): +-----------------------------------+-----------------------------------+ | **Eucaryotic cells** | **Procaryotic cells** | +===================================+===================================+ | Size Typically \>10µ | Size Typically \< 5µ | +-----------------------------------+-----------------------------------+ | Nucleus present | No Nucleus | +-----------------------------------+-----------------------------------+ | Membrane components | No membrane components or | | /compartmentalisation | compartmentalisation | +-----------------------------------+-----------------------------------+ | Larger ribosomes | Smaller ribosomes | +-----------------------------------+-----------------------------------+ | Cell division -- mitoses and | Binary fission | | meiosis or budding | | | | Or Only asexual reproduction | | Or Sexual reproduction present | | +-----------------------------------+-----------------------------------+ 3. You have stained a heat-fixed smear by the method of Gram. Which term refers to the general type of staining involved? (4 marks) a. simple stain (b) negative stain (c) differential stain (d) fluorescent stain 4 - Heat sterilization is normally undertaken in an autoclave. The most usual conditions are: (4 marks) 5. An open system in which the growth rate is controlled by adding nutrient (present in limiting quantities) at the same rate that medium containing microorganisms is removed is called: (4marks) a. Manostat b- Chemostat c- Batch culture d- Culturostat 6- In a Chemostat, the dilution rate can be calculated using the following formula: (4 marks) 7. List advantages and disadvantages of using a hemocytometer/counting chamber to determine the number of microbial cells in a sample. (4 marks) 8. Define the decimal reduction time (D value) and state how it is calculated: (4 marks) 9. 10. 11-. Examine the two lists and match dimensions provided to the bacterial species put number in brackets. ( 4 ) *Escherichia coli* ( 1 ) *Treponema pallidum* ( 2 ) *Thiomargarita namibiensis* ( 3 ) *Staphylococcus aureus* \(1) \~0.5 µm X 10-25µm \(2) \~750µm \(3) \~2µm \(4) 1.0 µm X 2µm 12- The rigidity and shape of the bacterial cell is provided by the...... (2 marks) \(a) cell membrane (b) peptidoglycan \(c) the lipopolysaccharide (d) the teichoic acid 13- The enzyme, lysozyme, induces lysis in bacteria because it interferes with............ (2 marks) \(a) transpeptidation which is essential for peptidoglycan cross-linking \(b) integrity of the β-1, 4 linkage between NAM and NAG in peptidoglycan \(c) cell membrane permeability by degrading phospholipids \(d) flagellar rotation resulting in autolysis 14\. What bacterial structure contains Dipicolinic Acid \_\_\_\_\_\_Endospores\_\_\_\_\_\_ ? (2 marks) 15\. List two species of endospore forming bacteria: (4 marks) a. (b) 16 The virus protein shell is called............. (4 marks) a- Envelope b. Viromere c- Capsid d. Membranous layer 17 Which of these diseases is not a viral disease? (4 marks) a\. Smallpox b. Herpes c\. Measles d. Diphtheria 18- What do the terms PFU and CFU mean in microbiology? (4 marks) PFU=\_\_\_\_**plaque-forming unit**\_\_\_\_\_\_\_\_\_\_\_\_\_\_ CFU=\_\_\_\_\_Colony forming unit\_\_\_\_\_\_\_\_\_\_\_\_\_\_\_\_ 19- List two types of cytopathic effects that results from viral infection; (4 marks) \_\_Synsytia (multinucleate cells)\_\_\_\_ \_\_\_\_\_\_Inclusion bodies or Clamping cells\_\_\_\_ 20 - True or false (4 marks) - - - - 21 - True of false (4 marks) - Fungi are heterotrophs that are involved in decomposition of organic matter \_\_\_T\_\_\_\_\_ - In Fungi spores can only be produced by sexual reproduction \_\_\_\_F\_\_\_\_\_ - Mycorrhizae fungi are plant pathogens deleterious to plant growth \_\_\_\_F\_\_\_\_\_ - Coenocytic hypha are those that have numerous septa \_\_\_\_\_F\_\_\_\_\_ 22- What are the four nutrition types/categories in microorganisms? (8 marks) \_\_Photo auto(litho)tophs\_\_\_\_\_\_\_\_\_ \_\_\_\_\_\_Photo hetro(organo)torphs\_\_\_\_ \_\_\_Chemo auto(Litho)torphs\_\_\_\_\_ \_\_\_\_Chemo hetro(organo)trophs\_\_\_ 23- What are the four major systems of nutrient uptake in bacterial cells? (4 marks) \_\_\_Simple/passive diffusion\_\_\_\_ \_\_\_\_Facilitated diffusion \_\_\_\_ \_\_\_ Active transport \_\_\_\_\_ \_\_\_\_\_\_ Group translocation \_\_\_\_\_\_ 24- When the viral genome is integrated into the host chromosome but does not result in the lysis of the host cell, it is referred to as............ (2 marks) \_\_\_\_\_\_Lysogeny or lysogenic cycle\_\_\_\_\_ 25- The causative agent for mad cow disease and some other neurodegenerative diseases are...... (3 marks) a. Prions b -- Viroids c- Viruses d- Bacteria e- Fungi 1. Endospores are produced by members of which of the following genera?