NAME: Microbiology BI234 MUST be written and will not be accepted as a typed document. 1.

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1 Chapter 3 Study Guide Explain the 3 main characteristics that help differentiate prokaryotes from eukaryotes. What are the 7 structures/substances found in all bacterial cells? What are 8 specific structures that are found in some but not all bacterial cells? Draw a picture of a bacterial cell and label the various structures found in Figure 3.1. Also, briefly describe the function of each structure 1. cell membrane 2. bacterial chromosome/nucleoid 3. ribosome 4. actin cytoskeleton 5. cytoplasm 6. fimbriae 7. outer membrane 8. cell wall 9. pilus 10. capsule 11. inclusion 12. plasmid 13. flagellum 14. endospore NAME: Microbiology BI234 MUST be written and will not be accepted as a typed document What are some of the life functions that prokaryotic cells accomplish as a single cell? Page 1 of 6

2 A common average size of bacteria is about 1 micron (um)(micrometer) wide which is easy to remember since we're in micro biology We will be observing the morphology of many bacteria over the quarter and some will be pleomorphic. What does pleomorphic mean? Describe or draw the 5 1. most common shapes of bacteria Draw the structures of: diplococcus staphylococcus streptococcus streptobacilli There are 2 major groups of appendages that provide different functions. Briefly describe their structure and general function. There are 2 major groups of bacterial surface coatings (glycocalyces) that provide different functions. Briefly describe their structure and general function. Group 1= flagella Group 2= fimbriae Group 2= pilus (pili) Group 1= slime layer Group 2= capsule Page 2 of 6

3 Explain how an encapsulated bacterial cell has greater pathogenicity like in the case of Streptococcus pneumoniae. Explain how biofilms are formed and why they are a problem in clinical settings. Describe the function of the cell wall. Draw a picture of a Gram positive cell wall and label its components. Draw a picture of a Gram negative cell wall and label its components. Compare and contrast the Gram positive and Gram negative cell walls by stating one similarity and one difference. Describe the steps of the Gram stain 1. Step Description of Gram + Description of Gram Page 3 of 6

4 Explain the clinical importance of the Gram stain. Explain how the mycolic acid found in nontypical cell walled Mycobacterium tuberculosis contributes to its virulence. Explain how mycoplasmas are different from other bacteria. Explain how the outer membrane found in Gram negative bacteria is different than its interior cell membrane. Briefly describe the structure of the cytoplasmic (cell) membrane. Explain the varied functions of the cell membrane. Explain how the differences in the cell envelopes between gram negative and gram positive bacteria affect their treatment with antimicrobial chemicals. Page 4 of 6

5 Describe the structure and function of the following structures found inside of bacterial cells. Chromosome Plasmids Structure Function Ribosomes Inclusions Cytoskeleton Explain the benefit of endospores that are formed by a few genera of bacteria including Bacillus and Clostridium. Describe the stimulus that causes bacteria to sporulate and form an endospore. Explain how endospores germinate. Explain why endospores can be a problem in clinical settings. List some of the differences between archaea and bacteria. Explain the importance of classification systems. Which Bergey's manual do you think we'll be using in this class and why? Explain how the use of the term, species, is different for animal species versus bacterial species. Page 5 of 6

6 How do microbiologists differentiate between bacteria of the same species that have slightly different characteristics? What s working well and what s a suggestion to help things work better? Page 6 of 6