week 4

Question 1

what elements are essential for all microorganisms

Answer 1

H, C, N, O, P, S

Question 2

what is the cell mostly made out of ?

Answer 2

proteins (55%)
RNA (20.5%)

Question 3

macronutrient

Answer 3

required in large amounts and play key roles in cell structure and metabolism
C, H, and O

Question 4

micronutrient

Answer 4

present in much smaller amounts and are involved in enzyme function and maintenance of protein structure
- manganese, zinc, and nickel

Question 5

List of growth factors

Answer 5

PABA
folic acid
Biotin
B12
B1
B6
Nicotinic acid
riboflavin
pantothenic acid
lipoic acid
vitamin k
coenzymes M and B
F420 and F430

Question 6

minimum temperature

Answer 6

transport processes so slow that growth cannot occur

Question 7

maximum temperature

Answer 7

protein denaturation
collpase of the cytoplasmic membrane
thermal lysis

Question 8

psychrophile

Answer 8

optimal growth in cold tempertaures

Question 9

mesophile

Answer 9

optimal growth around (36-39)

Question 10

thermophile

Answer 10

optimal growth around 60

Question 11

hyperthermophile

Answer 11

live in very hot environments
Use Ca2+ to help stabilize proteins and are adapted to high temps

Question 12

osmolarity

Answer 12

the total concentration of a solute

Question 13

halophiles

Answer 13

• live in high solute environments
• have things inside cell that aren’t membrane permeable so they contribute to osmolarity of the cell so water does not rush out

Question 14

Obligate aerobe

Answer 14

O2 is required
aerobic respiration

Question 15

Facultative anaerobe

Answer 15

not required, but grows better with O2
aerobic respiration, anaerobic resp., fermentation

Question 16

Microaerophilic

Answer 16

required but at levels lower than atmospheric
aerobic respiration

Question 17

aerotolerant

Answer 17

not required and grow no better with O2 present
fermentation

Question 18

obligate anaerobe

Answer 18

O2 is harmful or lethal
fermentation or anaerobic respiration

Question 19

what does oxygen produce?

Answer 19

superoxide
hydrogen peroxide
hydroxyl radical

Question 20

what do aerobes produce

Answer 20

superoxide dimutase
catalase
peroxidase

Question 21

barophilic

Answer 21

require pressure because they have adapted membranes

Question 22

what does optical density measure?

Answer 22

live and dead cells and everything else in the sample

Question 23

what does membrane filtration measure?

Answer 23

measures alive bacteria

Question 24

bacteriostatic

Answer 24

prevents growth but does not kill or lyse

Question 25

bactericidal

Answer 25

dead but not lysed (remains intact)

Question 26

bacteriolytic

Answer 26

cells die and they are lysed (irreversible)

Question 27

decimal reduction time

Answer 27

time it takes to kill 90% of bacteria

Question 28

sterilization

Answer 28

destruction or removal of all viable organisms - inc. endospores!!

Question 29

disinfection

Answer 29

killing, inhibition, or removal of disease causing organisms but not endospores

Question 30

sanitization

Answer 30

reduction of microbial population to levels deemed safe

Question 31

antisepsis

Answer 31

prevention of infection of living tissue by microorganisms - kill or inhibit growth when applied to surface of tissue

Question 32

chemotherapy

Answer 32

kill or inhibit internal microorganisms

Question 33

physical methods to kill bacteria

Answer 33

high moist heat - even kills endospores low moist heat - kills pathogens present but does not sterilize UV radiation Gamma radiation

Question 34

mechanical methods to kill bacteria

Answer 34

membrane filtration

Question 35

phenolics

Answer 35

act by denaturing proteins and disrupting cell membranes does not kill spores but kills other bacteria

Question 36

alcohols

Answer 36

bactericidal, fungicidal but does not kill spores denatures proteins

Question 37

Halogens

Answer 37

kills bacteria, fungi, viruses may kill spores at high concentrations

Question 38

aldehydes

Answer 38

crosslink proteins stops metabolic activity kills most bacteria, fungi, and spores

Question 39

Quaternary ammonium compounds

Answer 39

detergents that have antimicrobial activity kill most bacteria BUT not endospores

Question 40

Hydrogen peroxide

Answer 40

kills most bacteria, viruses, and fungi