Microbiology Exam 3

Question 1

Defenses of the body against infection

Answer 1

1. Mechanical defenses
2. Physiological defenses
3. Chemical defenses

Question 2

Mechanical defenses

Answer 2

anatomical barriers; Example: Skin, mucous membranes, bony encasements

Question 3

Physiological defenses- functional

Answer 3

i. Inflammation
ii. Fever
iii. Phagocytosis- cell ingestion

Question 4

Chemical defenses

Answer 4

i. Body secretions
ii. Antibodies (Immunoglobulins-Ig)
iii. Interferon

Question 5

Lysozyme

Answer 5

enzyme present in tears that kills bacteria

Question 6

Gastric juice

Answer 6

acidic, HCl, pH below 7.0 to protect you digestive system

Question 7

Antibodies (Immunoglobulins-Ig)

Answer 7

are specific proteins produced by the body in response to a specific foreign protein

Question 8

Interferon

Answer 8

virus-neutralizing substance produced individually

Question 9

Immunology

Answer 9

the study of immunity; immunity a highly state of resistant to an infection or disease

Question 10

Antigens

Answer 10

these are foreign proteins against which the body forms certain antibodies

Question 11

Antibodies

Answer 11

specific proteins produced by the body in response to a specific foreign protein

Question 12

Characteristics of antigen

Answer 12

antibody reactions: very specific; true antibodies will have bivalent receptor sites; if incomplete, allergic reaction

Question 13

Sterilization

Answer 13

process of completely removing and destroying all life forms and their products (exotoxins, endospores) in or on a substance

Question 14

Disinfection

Answer 14

process by which you destroy all pathogenic organisms by physical or chemical means

Question 15

Antisepsis

Answer 15

the prevention or inhibition of the growth of microorganisms, without necessarily killing them.

Question 16

Methods of Control- Physical

Answer 16

1. Scrubbing-
2. Heat-
3. Cold- refrigeration
4. Ultraviolet (UV) light- bactericidal

Question 17

Heat

Answer 17

a. Incineration- burning flaming as a lab technique
b. Dry heat- convection oven
c. Moist heat-

Question 18

Moist heat

Answer 18

i. Boiling
ii. Free-flowing steam
iii. Steam under pressure: autoclave 121 degree C is standard temperature of an autoclave; 15lbs is standard amount of pressure. Standard Exposure time 15 minutes; best means of physical of true steralization

Question 19

Methods of Control- Chemical

Answer 19

1. Disinfectants- chemical agents proven to kill pathogens
2. Factors influencing the action of disinfectants
3. Disinfectants suitable for mortuary procedures

Question 20

Chemical- Disinfectants-

Answer 20

a. Germicide- killing of germs
b. Bactericide- killing of bacteria
c. Fungicide- killing of fungi (yeast & molds)
d. Viricide- chemical agents that kill viruses
e. Insecticide- agents that kills insects
f. Larvacide- chemical agents that kill larva (nits; head lice)

Question 21

Factors influencing the action of disinfectants

Answer 21

a. Nature of the disinfectant
b. Concentration of the disinfectant
c. Nature of the material to be disinfected
d. Number of microorganisms present
e. Kind of microorganisms present
f. Time of exposure to disinfectant
g. Temperature of disinfectant during exposure
h. pH of disinfectant during exposure

Question 22

Halogens- salt formers

Answer 22

i. Hypochlorites (bleaches)
1. Ex: NaOCL- household bleach 1:10 dilution; standard external disinfectant per CDC
ii. Iodophors- iodine; Betadine

Question 23

Alcohols

Answer 23

i. Ethyl alcohol (ethanol)

ii. Isopropyl alcohol (rubbing alcohol)

Question 24

Aldehydes- alcohols deprived of hydrogen

Answer 24

i. Formalin (formaldehyde solution) compare strength using index (index- no. of grams of formaldehyde gas dissolved in 100mL of solution)
ii. Glutaraldehyde- 2% as Cidex

Question 25

Phenolic compounds

Answer 25

i. Phenol (carbolic acid) – acidic in pH;
ii. Cresols (Lysol)
iii. Hexachlorophene

Question 26

Quaternary ammonium compounds

Answer 26

i. (Examples: Benzalkonium Chloride and Zephrian Chloride)

Question 27

Natural (innate) immunity

Answer 27

inborn any immunity in which you are born with upon conception
• Racial- incidence of sickle cell anemia
• Species- distemper non-human
• Individual- interferon

Question 28

Naturally Active

Answer 28

having the disease & recovering from it

Question 29

Naturally Passive

Answer 29

Colostrum (first mothers milk secereted after birth), breast feeding, placental transfer of antibodies

Question 30

Artificially acquired

Answer 30

by shot or immunization

Question 31

Artificially Active

Answer 31

vaccines (DPT), toxoids, attenuated strains, live or dead, Microorganisms, extracts (PPD)

Question 32

Artificially Passive

Answer 32

Conveyed by artificial means instantaneously through a pre-formed antibody. Last the shortest time - 3-7 days. Examples of these artificial means are: immune serum, antiserum, gamma globulin.