Exam Two: Chapter Eleven

Front 1

Sterilization

Back 1

A process that destroys or removes all viable microorganisms, including viruses

Reserved for inanimate objects, such as surgical instruments, syringes, and commercially packaged foods

An object is either sterile or it is not sterile, there is no in between

Front 2

Bactericide

Back 2

A chemical that destroys bacteria, except for those in the endospore stage

Front 3

Bacteriostatic

Back 3

Agents that prevent the growth of bacteria on tissues or on objects in the environment

Front 4

Germicide

Back 4

Any chemical agent that kills pathogenic microorganisms

Can be used on both inanimate materials and living tissue

CANNOT kill resistant microbial cells

Front 5

Disinfection

Back 5

The use of a physical process or a chemical agent to destroy vegetative pathogens, but not bacterial endospores

Process can remove the harmful products of microorganisms

Toxic to living tissue in the concentration required to be effective, therefore used on inanimate objects

Front 6

Asepsis

Back 6

Any practice that prevents the entry of infectious agents into sterile tissues thus preventing infection

Front 7

Antiseptic

Back 7

Chemical agents that are applied directly to exposed body surfaces, wounds, and surgical incisions to inhibit or destroy vegetative pathogens

Front 8

Mode of Action

Back 8

An antimicrobial (disinfectants and antiseptics agent's adverse effect on cells

Front 9

Sanitization

Back 9

Refers to any cleansing technique that removes debris, microorganisms, and toxins, and in this way reduces the potential for infection and spoilage

Soaps and detergents are the most commonly employed sanitizers

Is often preferable to sterilization

Front 10

Factors that affect Microbial Death

Back 10

1. the number of microbes present, the high load of contaminants requires more time to destroy

2. the nature of the microorganisms in the population

3. the temperature and pH of the environment

4. the concentration (intensity/dosage) of the agent

5. the mode of the agent, how does it kill the microorganism

Front 11

Four Modes of Actions

Back 11

1. Effect on cell wall- damage wall by blocking its synthesis, digesting it, or breaking down its surface leaving cell fragile

2. Effect on cell membrane- if membrane is destroyed cell loses its selective permeability and can neither prevent the loss of vital molecules nor bar the entry of damaging chemicals

3. Effects on protein and nucleic acids synthesis- block protein synthesis inhibiting metabolism and growth or block DNA replication

4. Effects on protein function- denature cells proteins through pH, temperature or block active site of enzymes

Front 12

Physical Control: Moist Heat

Back 12

Can establish thermal death time (how long it takes to kill the organism) and sterilizes and controls faster than dry heat

Methods:
- non-pressurized steam
- boiling water
- pasteurization
- steam under pressure (will control endospores), autoclave is most effective

Front 13

Physical Control: Dry Heat

Back 13

Incineration

- cremation
- flaming loop in lab

Front 14

Physical Control: Cold and Desiccation

Back 14

Cold temperatures are biostatic- do not kill microorganism, just slows down the growth of the culture

Desiccation- dehydrating cells

lyophilization- freezing and dehydrating microorganism

Front 15

Physical Control: Radiation

Back 15

Causes the breakdown of DNA and structure of microorganism

Ionizing- gamma, x, and cathode rays
Non ionizing- UV rays

Front 16

Physical Control: Filtration

Back 16

Mechanical removal of microorganisms

ex) water system filtration

Front 17

Chemical Control Agents: Halogens

Back 17

- Chlorine- gaseous and liquid state disinfect water
EX) hypochlorite: bleach
EX) Chloramines

- Iodine- topical antiseptic, treatment for burns, and disinfection of inanimate objects

Front 18

Chemical Control Agents: Phenols

Back 18

- Phenol: general disinfections

- Bisphenols: Lysol

- Chlorhexidine: mild low toxicity, hand scrubbing, surgical incision site, and wound degermer (only antiseptic phenol)

Front 19

Chemical Control Agents: Alcohols

Back 19

70% alcohol is most effective

Front 20

Chemical Control Agents: Hydrogen Peroxide

Back 20

Acts as both an antiseptic and a disinfectant depending upon its concentration

3% and below= antiseptic
4% and above= disinfectant

will kill normal flora in human body and can breakdown tissue, therefore not heavily used as antiseptic

Front 21

Chemical Control Agents: Heavy Metals

Back 21

Copper, Gold, and Silver

All metals, esp heavy metals, have an anti microbial property

Front 22

Chemical Control Agents: Aldehydes

Back 22

Formaldehyde, 1% solution (formalin) can be used in ponds to control algae without killing animals

Front 23

Chemical Control Agents: Dyes

Back 23

Eosin Methylene Blue (EMB) will control the growth of gram positive organisms

Front 24

Chemical Control Agents: Acids and Alkalis

Back 24

Adjusts the pH therefore killing organism