Exam 4

Question 0

How do you measure the efficiency of a disinfectant

Answer 0

1. Use dilution test- flask dipped in bacteria then disinfectant
2. Filter paper method(Kirby-Bauer)- dipping paper in disinfectant then lay it over plate of bacteria

Question 1

Pasteurization is what kind of method

Answer 1

Disinfection

Question 2

Types of chemical methods of microbe control

Answer 2

1. Phenol (lister)
2. Bisphenols
3. Biguanides
   4.halogens
   5 alcohols
4. Heavy metals
5. Detergents

Question 3

Big unaided

Answer 3

Example: chlorhexidine

Targets cell membrane but not spores
Less toxic than phenolics

Used for surgical scrubs

Question 4

Halogens

Answer 4

1. Iodine
   Binds amino acids like tyrosine
   Effective against spores
   Antiseptic
2. Cl2 (chlorine) (quick)
   Must combine with water
   Strong oxidizer

Question 5

Alcohols

Answer 5

1. Don’t kill endos
2. Denature proteins by causing cell mem probs
3. Evans quickly
4. Determine for shots

Question 6

Heavy metals

Answer 6

1. Silver, mercury, copper
2. Oligodynamic action
3. Suffer nitrate for eye drops for new borns
4. Silver infused stuff

Question 7

Two types of detergent by their charge

Answer 7

Anionic

Cationic

Question 8

Anionic

Answer 8

Mainly used to remove bac from surface

Question 9

Cationic detergent

Answer 9

Disrupts membrane, protein denaturing

Question 10

Organic acids

Answer 10

Damage plasma mem

Food preserves

Question 11

Aldehydes

Answer 11

Inactivates proteins

Glutoraldehyde- equipment use
Formaldehyde- embalming fluid

Question 12

Gases

Answer 12

Ethylene oxide
Denatures proteins
Kills spores 4-18 hrs
Toxic/explosive
Sterilizes

Question 13

What two characteristics do antibiotics have to exhibit to be effective treatments for bacterial infection

Answer 13

Must have:

1. Selective toxicity (only hurt microbes)
2. Target has to be essential

Question 14

Selective toxicity east to hard

Answer 14

Gram +.                   Easy to fight
Gram -
Fungi.                       Moderate 
Intracellular 
Viruses.                    Hard to fight

Question 15

Why are intercellular and viruses harder to fight

Answer 15

Because bacteria have walls (we don’t)which can be targeted

Intros cellular and viruses are inside put own cells

Question 16

When did Fleming discover penicillin

Answer 16

1929

Large scale production in 1940

Question 17

What did the figure out about antibiotics in 1956

Answer 17

Active against GROWING bac only (cell wall synthesis)

Poor activity against gram- bac.

Destroyed by acid

Question 18

What is penicillinase

Answer 18

Enzyme that is produced by bacteria that breaks down penicillin.

Question 19

Similar-synthetic antibiotics

Answer 19

1. Acid resistant
2. Less allergenic
3. Penicillinase resistant
4. Reach cns
5. Active against gram - (different two chemical groups and combining them)

Question 20

Describe mersa

Answer 20

Spherical
Gm + ,
Irregular clusters like grapes

Question 21

When did antibiotics become popular

Answer 21

1940

Curing “simple” ailments

Used to save loves in ww2

Question 22

When did people start seeing resistance to antibiotics?

Answer 22

Early on so they just started using more of the drug or give them a different drug

Today, lots of resistant forms are appearing, even new ones

Question 23

How do drugs develope a resistance

Answer 23

• microbes divide rapidly
• because they are dividing so rapidly, errors in DNA occur causing a mutation
• microbes can actually pass genes from one microbe to a different one
• some of these bac have mutations that help them be antibiotic resistant
• they survive and divide even after antibiotic

Question 24

What can resistant bacteria be compared to

Answer 24

Accelerated natural selection

Question 25

How are physicians contributing to the antibiotic resistance Orin

Answer 25

Using too many broad spectrum drugs | Using exotic drugs first