Metabolism
Cleaning/Sterilization
Cleaning/Sterilization
Metabolism 2
Random 2
100

What is chemiosmosis? (in context of metabolism)

The process of H+ moving across a semipermeable membrane down an electrochemical gradient in order to produce ATP

100

What is asepsis?

Absence of significant contamination

100

What is the disk diffusion method used for?

Screening of antimicrobial agents 

100

What is enrichment media?

It is a media that is used to grow a lot of microbes before further culturing (usually a 1st media)

100
Name one type of gram negative bacteria, genus and species

Neisseria meningitidis, E.coli, Bacteroides, Pseudomonas, lactobacilli

200

What is the purpose of the krebs cycle?

To thoroughly oxidize pyruvate, this cycle provides a lot of electron carriers that will donate electrons to the ETC (NADH, FADH2)

200

What is non-ionizing radiation used for? (UV-B)

Treatment of spaces 

200

Aldehydes are commonly used to clean what kind of material?

Commonly used for disinfection of sensitive instruments that cannot be put in an autoclave

200

What is the chemical requirement for bacterial growth?

A lot of bacteria use carbon-containing compounds as either a source of carbon (chemoheterotrophs) or an electron source for metabolic activity (fermentation, respiration)  
200

What is MBC and MIC?

Minimum bacterial cidal concentration 

Minimum inhibitory concentration 

300

Explain the differences between aerobic respiration, anaerobic respiration, and fermentation.


Aerobic: Cellular respiration in the presence of oxygen. Glycolysis - krebs cycle - ETC - higher ATP yield

Anaerobic respiration: Respiration without the presence of oxygen, the final electron acceptor is an inorganic molecule

Fermentation: Done in without oxygen, NET 2 ATP yield, makes some sort of end product out of pyruvate in order to recycle the electron carrier NAD 



300

What is an autoclave/what are its features?

An autoclave is a sterilization device that is considered the "gold standard" for sterilization. This is because it has to ability to kill endospores. The autoclave works by using steam under high pressure (moist heat - denatures proteins). It is used with heat-stable materials. 

300

What do phenol-derived disinfectants do to limit microbial growth? (what is their drug target)

Disrupts plasma membranes and denatures proteins.

300

Name the 6 conditions that influence bacterial metabolism.

temperature, pH, tonicity, oxygen conditions, substrate concentration, enzyme inhibition 

300

What is chemically-defined and complex media?


Chemically-defined media: The exact chemical composition is known (specifically weigh everything out) Used for assays with specialized bacteria

Complex media: The exact chemical composition is not known. Made from extracts, digests of yeast and meat, etc.

400

What toxic substances are produced from aerobic respiration? How do bacteria detoxify these compounds? 

Toxic: O2- and H2O2, enzymes detoxify these compounds.

400
What treatment would I use on an IV line to control/prevent microbial growth?

Ionizing radiation; useful on heat-labile materials

400

What type of materials are used with dry heat? how does dry heat kill microbes?

heat-stable, oxidation. 

400

Name the 8 factors that can influence the "growth" of microorganisms

1. Microorganism's metabolism

2. Enviornmental conditions

3. Nutrients

4. Temperature

5. pH

6. oxygen

7. tonicity

8. competition with other microbes 

400

Name 3 features of an enzyme 

3D protein, shape is critical to function, substrate specific, biological catalyst, catalyze one specific reaction, cells' genetics determine what it can hydrolyze/synthesize. In cell or secreted

500

Explain the general process of the electron transport chain in aerobic respiration

  1. Electrons are donated by NADH and FADH2 to the electron transport chain

  2. As these electrons are passed from protein to protein, H+ pass through the membrane via the transmembrane proteins into the extracellular space

  3. This creates a gradient and concentration of protons (inside of the cell more negative than the outside of the cell)

  4. Electrons eventually come to the last protein and get passed off to the final electron acceptor, oxygen, and forms water

  5. These H+ move down their concentration gradient back into the cell via ATP synthase

  6. The movement of H+ through ATP synthase facilitates the the formation of ADP + P into ATP 

500

What are the three heavy metals used for chemical control of microbial growth? How do these kill bacteria?

Heavy metals: Silver, Mercury, Copper

Kill by disrupting plasma membranes and denaturing proteins 

500

Name the features of "filtration" to control microbial growth

Removes/separates microbes.

neither cidal nor static, used with pyrogens.

500

Describe the lag phase, log phase, and stationary phase of the microbial growth curve

Lag: The bacteria are sensing the enviornement and expressing genes; not much is happening

Log phase: Exponential growth, most metabolically active at this point, and most antibiotic sensitive

Stationary phase: Bacteria have either depleted the media or produced toxic end products that have built up; they are dying at the same rate as they are dividing 

500

When can your normal flora cause infections?

When they are out of place, or they are out of balance 

- microbes in your normal flora keep each other in check, if this balance is disrupted, it can cause an infection