Lecture 1

Question 1

What are some examples of culturing techniques?

Answer 1

Artificial culture medium
Pure culture
Agar plate
Gram stain
Petri dish

Question 2

What was Germ’s theory?

Answer 2

Proposed by Louis Pasteur in 1861 that all microorganisms can cause diseases

Question 3

What were Koch’s postulates?

Answer 3

Causative agent must be in all cases
Isolate agent from diseased patients
Inoculate agent to healthy susceptible host
Re-isolate to inoculate host

Question 4

What is the difference between an endemic, epidemic and a pandemic?

Answer 4

Endemic is constantly present in a population or region, with relatively low spread
epidemic is sudden increase in cases spreading through a large population
Pandemic is a sudden increase in cases across several countries and continents of the world

Question 5

What are some ways reemerging diseases may occur?

Answer 5

Public health measures loosening
Lower vaccination rates
antibiotic overuse

Question 6

____ is a study of what, when, where and why diseases occur and to whom

Answer 6

Epidemiology

Question 7

What are some factors that affect the likelihood of contacting a disease?

Answer 7

Females contact more than men
Certain races
socio-ecomic status

Question 8

What are some examples of epidemics?

Answer 8

Ebola in West Africa
Nipah in India
Cholera in Burkina Faso
Rabies in Tanzania

Question 9

What are some ways to slow diseases spread?

Answer 9

Wash hands
don’t touch mouth or hands without sanitizing
Cover mouth and nose when coughing or sneezing
Practice social distancing
disinfect househols surfaces regularly

Question 10

What does staining increase?

Answer 10

Contrast

Question 11

The chromophore of basic dye is a ____ while the chromophore of an acidic dye is a ________

Answer 11

cation (+)
anion (-)

Question 12

What is the use of a single basic dye called?

Answer 12

Simple stain

Question 13

What is mordant used for?

Answer 13

To hold the stain or coat the specimen to enlarge it

Question 14

____ is staining the background instead of the cell

Answer 14

negative staining

Question 15

________ staining uses more than one stain to diffentriate between microbes or structures

Answer 15

Differential

Question 16

What does special staining use?

Answer 16

A dye with affinity to particular structures

Question 17

What are some examples of differential stains?

Answer 17

Gram stain and acid-fast stain

Question 18

What color does bacteria appear in Gram postive stain?

Answer 18

Dark blue to violet

Question 19

What color does bacteria appear in Gram negative stain?

Answer 19

Pink to red

Question 20

What are the steps of gram stain?

Answer 20

1. Bacterial smear
2. Appplication of crystal violet (60 sec)
3. Application of iodine (60 sec)
4. Application of ethyl alacohol (15 sec)
5. Counterstain with safranin (60 sec)

Question 21

What are the shapes of gram postive and negative bacteria?

Answer 21

GN - Rod
GP - Cocci

Question 22

What is acid -fastness?

Answer 22

Property of resistance to decolorization

Question 23

What are the colors of postive and negative acid fastness?

Answer 23

AF + - Red
AF - - Blue

Question 24

What are the steps of acid-fast?

Answer 24

1. Apply primary stain of carbofulshin for 30 seconds
2. Heat fix cells to slide using flame
3. Decolorize with acid alcohol for 15-20 seconds
4. Apply counterstain of methylene blue for 30 seconds then rinse excess stain

Question 25

What are some other examples of stains?

Answer 25

Endospore, flagella, negative staining for capsules,