X_Exam1 Mfm2_9

Front 1

what are the 3 ways in which to measure bacterial growth:
1.
2.
3.

Back 1

1. total counts
2. viable counts
3. measurements of light scattering

Front 2

what type of bacterial counts does the following describe:

directly counting a sample of the culture and getting the total number of cells per ml, both viable and non-viable

Back 2

total counts

Front 3

what type of bacterial counts does the following describe:

sample of culture is plated on agar and counted

Back 3

viable counts

Front 4

what type of bacterial counts does the following describe:

a spectrophotometer is used to determine the amount of light that passes through the culture

Back 4

measurement of light scattering

Front 5

use the image to calculate the colonies in the flask from each of the plates:

Back 5

1. 10^2 x 10 x 8950 = 8.95 x 10^6
2. 10^4 x 10 x 93 = 9.3 x 10^6
3. 10^5 x 10 x 7 = 7 x 10^6

Front 6

what are the 3 phases of growth:
1.
2.
3.

Back 6

1. lag
2. exponential
3. stationary
(4. death)

Front 7

in a growth curve, at the point cells stop dividing is called ... phase

Back 7

stationary

Front 8

1. what is the definition for aerobes:

2. what is the definition for anaerobes:

Back 8

1. organisms that can use oxygen to grow

2. organisms that cannot use oxygen

Front 9

aerobes grow by ... and use oxygen to oxidize ...

Back 9

respiration
NADH

Front 10

what are the 3 classes of aerobes:
1.
2.
3.

Back 10

1. obligate aerobes
2. microaerophiles
3. facultative anaerobes

Front 11

what are the 2 obligate aerobes discussed in class:
1.
2.

Back 11

1. Mycobacterium
2. Pseudomonas

Front 12

... require oxygen for growth but it must be below atmospheric O2 and the 2 examples of these organisms discussed in class are:
1.
2.

Back 12

microaerophiles
1. Campylobacter
2. Helicobacter

Front 13

... will use oxygen if it is present but can grow by fermentation.

the organism of this type discussed in class is ...

Back 13

facultative anaerobe
Escherichia

Front 14

... cannot use oxygen even when it is present and some are killed by the presence of O2, these are called ...

Back 14

anaerobes
obligate anaerobes

Front 15

what are the 2 examples discussed in class that are obligate anaerobes:
1.
2.

Back 15

1. Bacteroides
2. Clostridium

Front 16

what are the 2 diseases of fermentation discussed in class:
1.
2.

Back 16

1. lactose intolerance
2. gas gangrene (myonecrosis)

Front 17

what causes lactose intolerance:
what happens when person drinks milk who is lactose intolerant:

Back 17

person is missing lactase enzyme
the lactose reaches the large intestine and is fermented by anaerobic bacteria

Front 18

what do people get diarrhea with lactose intolerance:

Back 18

when the lactose is fermented by the bacteria, lactate, acetate, and formate are also produced causing water to be drawn into the large intestine

Front 19

what is the bacteria that causes myonecrosis:

Back 19

Clostridium perfringens

Front 20

what are the 3 classifications based on optimum growth temperature and what are their optimal temperatures:
1.
2.
3.

Back 20

1. psychrophile (0-20C)
2. mesophile (25-40C)
3. thermophile (45-80C)

Front 21

organisms that can grow at 0C but have a temperature optimum of 20 to 40C are called ...

Back 21

psychrotolerant

Front 22

what are the 2 psychrotolerant organisms discussed in class and what do they infect:
1.
2.

Back 22

Listeria monocytogenes - refrigerated foods (milk, cheese, raw veggies)
Yersinia enterocolitica - refigerated blood products