ASU MIC 205 EXAM 1 | questions and answers | with complete solution.

ASU MIC 205 EXAM 1 | questions and answers | with complete solution. Hershey and Chase performed an experiment in order to determine how bacteriophages infect bacteria. What did they find? The bacteriophage injects DNA into the host cell. This was found because, after centrifugation, the pellet was radioactive The largest difference between a Gram + and Gram - bacterial cell is: The gram + cell has a much thicker peptidoglycan layer Why does a Gram + cell stain blue/purple in a gram stain? The Gram + cell stains blue/purple because crystal violet remains trapped in the thick peptidoglycan layer. dormant with no detectable metabolism. Endospores You have bacteria in need of staining, though you are aware that they have capsules. How do you stain them? Negative stain, such that the bacterial capsule remains clear. The phospholipid bilayer of the bacterial cell membrane consists of phospholipids with Hydrophillic heads and hydrophobic tails The peptidoglycan layer consists of NAG-NAM interbridges A visible group of identical bacteria, all originating from a single cell Microbial colonies Phage quantification can be used to Identify specific bacteria, down to the strain level, since bacteriophages are specific for certain bacteria. A selective property in MacConkey agar that prohibits growth of gram + bacteria is Crystal violet Serological tests take advantage of the ability of antibodies (immunoglobulins) to specifically bind to ______________ on the surface of bacteria. antigens The "barcode of life" for bacteria is the 16S rRNA gene that encodes for the bacterial ___________________. ribosome The closest known relatives to the least common ancestor are believed to be __________ and _________. loki and thor One large differentiating property of Archaea, as compared to bacteria is that Archaea do not have __________________. peptidoglycan The murein lipoprotein is only present in _________ cells and serves to _____________________. gram - , connect the outer and inner membranes together. Contained within the cell membrane and is not exposed to our immune system until after cell lysis. endotoxin Would a gram + or gram - cell be more sensitive to exposure to an antibiotic that acts on the peptidoglycan layer? Gram + Which of the following would best help a bacteria invade tissue? endoflagella A characteristic of bacteria that would best help them colonize the urinary tract is: fimbriae A glycocalyx (both capsules and slime layers) aid in bacterial survival because: they can both store nutrients and water to survive dessication and starvation This type of substance can move across the cell membrane without a permeate protein: small, lipid soluble A bacterial cell is placed in an environment where the cell is hypertonic to the surrounding solution. What will happen to the cell? The cell will swell and burst A toxin that is produced inside the cell and then exported to the outside of the cell is called an exotoxin In the process of phagocytosis, an immune cell will capture a bacteria and place it inside of a(n): phagosome T or F Some bacteria are able to regulate their osmolarity so that they can maintain an isotonic balance with the outer environment. true This bacteria produces the most potent toxin known, with only 0.09 ug needed to kill the average human: Clostr