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wk 9-20 pg42-49
micro wk 2. pg 43-2-49
Question | Answer |
---|---|
micro wk2. pg42-49 | (blank) |
What binds proteins involved in cell wall synthesis previnting cross linking of glycan chains by tetrapeptides? | a. Penicillin |
q. Is penicillin more effective against Gram positive bacterium? | a. Yes, due to increased concentration of PTG, also peniclin derivatives produced to protect against Gram negatives. |
q. where are lysozymes produced? | a. body fluids including tears and saliva. |
q. what breaks bonds linking NAG and NAM destroying structural integrity of cell wall? | a. Lysozymes |
q. Lysozymes are often used in laboratory to remove ________layer from bacteria. | a. PTG |
q. | (blank) |
Lysozyme enzyme often used in laboratory to remove PTG layer from bacteria, produces protoplast in G+ bacteria and produces ________________ in G- bacteria. | a. spheroplast |
q. Differences in cell wall account for differences in staining characteristics. Gram positive bacterium retain what kind of Gram stain? | a. Gram positive bacterium retain crystal violet iodine complex of Gram Stain. |
q. what lose crystal violet iodine complex? | a. Gram negative bacterium lose crystal violet-iodine complex. |
q. Some bacterium naturally lack cell wall, such as mycoplasma(causes pneumonia), thus antimicrobial directed towards cell wall are ineffective, but what gives the membrane its strength you say. | a. Sterols in membrane account for strength of membrane. |
q. Bacteria in what domain have a wide variet of cell wall types? | a. domain archaea, |
q. do they contain PTG? | a. no, but they do contain pseudopeptidoglycan. |
q. Layers external to the cell wall. What is the general function of the capsules and slime layer? | A. protects bacteria from hosts defenses and enables bacteria to adhear to specific surfaces. |
q. What is diff. between capsule and slime layer? | a. capsule is a distinct gelatinous layer and a slime layer is an irregular diffuse layer. |
q. most capsules and slime layers have a chemical composition of polysaccharide which is refered to as a _____________. | a. glycocalyx |
q.some bacteria have protein appendages which include____________ and _______________. | a. flagella and Pili |
q. Flagella are long protein structures that can rotate more than ten thousand revolutions per minor 82 miles per hour. and some are important in ________________. | a. bacterial pathogenisis. |
q. what are the three basic parts to a flagella? | a. filament, hook and basal body. |
q. What does the filament do? | a. filament extends to exterior and is made of proteins called flagellin. |
q. What does the hook do? | a. connects the filament to the cell. |
q. What does the Basal body do? | a. Basal body anchors the flagellum into the cell wall. |
q. Bacterian uses flagella for motility through sensing chemicals called? | a. chemotaxis |
q. If the chemical compound is a neutrient it acts a an ______________? | a. attractant |
q. if compound is toxic acts as an? | a. repellent. |
q. Flagellar Arrangement. A single flagellum at one pole? | a. Monotrichous |
q. A single flagellum at both poles? | a. Amphitrichous |
q. What is two or more flagella at one or both poles of the cell? | Lophotrichous. |
q. What is Peritrichous? | a. completely surrounded by flagella. |
q. What is considerabley shorter and thinner than flagella and is composed of protein subunits? | a. Pili |
q. what are the three functions of pili? | a. attachment, movement, conjugation. |
q. what are the pili called for attachment? | a. fimbre |
q. Is pili conjugation a mechanism of DNA transfer? | a. yes.*** |
Internal Structures. bacterial cells have a variety of internal structures, some of which are essential for life(chromosome- DNA, and Ribosome -synthesyze proteins, while others are optional and can confire selective advantages such as | a. plasmid, storage granules, and endospores. |
q. What resides in cytoplasm in nucleoid space, is typically single chromosome, circular double-stranded molecule,contains all genetic information and has no nuclear membrane? | a. Chromosome |
q. circular DNA molecule-generally 0.1%-10.0% size of chromosome? | a. Plasmid |
q. what is extrachromosomal(independently replicating) and encode characteristic-potentially enhances survival(antimicrobial resistance)? | a. Plasmid |
q. What are involved in protein synthesis and are composed of large and small subunits made of riboprotein and ribosomal RNA? | a. Ribosome |
q. what are Prokaryotic ribosomal subunits? | a. 30s +50s -70s |
q. Larger thatn eukaryotic ribosomes? | a. 40S +60S -80S differences often used as target for antimicrobials. |
q. what are an accumulation of polymers synthesized from excess nutrients (exp. glycogen)?f | a. Storage granules |
q. What are small protein compartments that provid buoyancy to cell, and regulat vesicles allowing organism to reach ideal position in environment? | a. Gas vesicles |
q. What are dormant cell types produced through sporulation theoretically remain dormant for 100 years and are resistant to damaging conditions such a heat, desiccation, chemicals and uv light? | a. Endospores |
q. a vegetative cell is produced through _____________. | a. germination. |
q. when does germinatiom occur. | a. after exposure to heat or chemicals but is not a source of reproduction. |
q. what two produce endospores? | a. Genus Bacillus and Clostridium produce endospores. |
q. what is sporulation | a. the production of endospores. |
Endospore formation is a complex ordered sequence. Bacteria sense starvation and begin sporulation. what is the first step of sporulation? | A. Growth stops. |
Step 2. | a. DNA duplicates |
step 3. | a. Cell splits unevenly |
q. what produces the forespore within the mother cell? | a. the cell splits and the larger component engulfs small component, producing a forspore within mother cell, |
q. how many membranes is the forspore enclosed by? | a. forespore is enclosed by two membranes. |
q.Step 4, what becomes the core of the endospore? | a. Step 4, the forespore becomes the core of the endospore. |
q. step 5? | a. PTG between bembranes forms core wall and cortex. |
q. what forms core wall and cortex? | a. PTG between membranes. |
q. step 6? | a. Mother cell proteins produce spore coat. |
q. what produces the spore coat. | a. Mother cell proteins. |
q. Step 7? | a. Mother cell degrades and releases endospore. |
q. what degrades and releases endospore? | a. mother cell. |
q. Intracellular Structure. where are endospores seen? | a. in Bacillus and Clostridium. |
Q. When do vegetative cells develope into endospores? | a. Vegetative cells develop into endospores when there is low amount of carbon or nitrogen. |
q. how many spores does one bacteria create? | a. one spore for one bacteria. |
q. how many spores from one fungi? | a. fungi can make millions of spores. |
q. Is moisture in the spores? | a. no, they are dry, (calcium inside), |
q. can spores be killed from heating, drying, freezing, toxic chemicals or radiation? | a. No |
q. Why are spores so resistant. | a. Resistance is because of thich spore coat and Dipicolinic acid in the coat.. |
q.what kind of acid is in the spore coat?q | a. Dipicolinic acid |
q. what are the only ways endospores can be destroyed? | a. by moist heat under pressure(autoclaves) or certain chemicals like glutaraldehydes or ethylene oxide. |
q. Who is my favorit group on the campus? | a. the D group, I love you guys and gal. :) |