Bacterial growth

Question 1

Binary fision?

Answer 1

Asexual reproduction
Exponential growth

2^0 –> 2^1 –>2^2

Question 2

Budding?

Answer 2

Unequal growth

One daughter cell dissimilar to the mother cell

Question 3

Turbidity?

Answer 3

The cellmass and can be measured by the OD as light scatteres by cellmass.

Question 4

Spectrophotometer?

Answer 4

Measures OD by the unscattered light from the cellmass. A wavelength is sett by the apparatus, ex OD600.

Question 5

Generation time?

Answer 5

1 cell –> 2 cells and the time between the events.

Question 6

Growth curve?

Answer 6

Lag
Exponential
Static
Death - Cryptic growth

Question 7

Culture media?

Answer 7

Defined - pre. amounts of IN/O organic chemicals and dH2O

Complex - Digestive products and dH2O

Question 8

Chemostat?

Answer 8

Medium added @ constant rate at the same time as spent is removed = Steady state where cell density and substrate [] do not change over time.

Question 9

Factors affecting growth?

Answer 9

T
P
O
H

Question 10

Temperature?

Answer 10

Rate of enzymatic activity in reactions

Cardinal temp - min -> opt -> max

Question 11

Types of T bacteria?

Answer 11

Psychropiles - low temp 
Mesophiles - mid temp 
Thermopiles - >45 
Hyperthermopiles - >80 
Extremopiles - High or Low temp

Question 12

Adaptations to T?

Answer 12

Cold - more alpha helices and less beta sheets and more polar
Cold shock proteins and cryoproteins

Hot -more beta sheets and more non-polar

Question 13

pH?

Answer 13

How the extracellular enviroments pH can change and are usually in a range of 5-9.

Question 14

Types of pH bacteria?

Answer 14

Neutropiles - 5.5-7.9
Acido piles - < 5.5
Alakalipiles - > 8

Question 15

H2O?

Answer 15

Solutes binds to H2O and makes it less available

aw = 0–>1 and opt. @ 0.98

Question 16

Types of NaCl basteria?

Answer 16

Halopiles - Req is absolute and can not be replaced by other solutes. 1-4% or 3-12%.
Halotolerant - Tol. some levels of dissolved solute
Extreme halopiles - 15-30% NaCl for growth
Osmopiles - Env. high in sugar
Xeropiles - Dry environment

Question 17

Hyperosmotic shock?

Answer 17

Cells lyse due to efflux of H2O by a sudden change in the extracellular [] of solute.

Question 18

Oxygen?

Answer 18

Shaking = aeration
Anoxic conditions - reducing agent
O2 –> H2O

Question 19

Groups of Aerobes?

Answer 19

Obligate - req. O2
Faculative - not req.
Micrpoaerophilic - req O2 in small amounts

Question 20

Groups of Anaerobes?

Answer 20

Obligate - Inhibited or die by oxygen

Aerotolerant - tolerant and can grow

Question 21

Oxygen reduction?

Answer 21

O2- H2O2 OH* –> H2O

Question 22

[R] Aerotolerant?

Answer 22

Proteinfree Mn - complex

O2-

Question 23

[R] Anaerobes?

Answer 23

Superoxide reductase
O2- –> H2O2
No production of O2

Question 24

[R] Aerobes?

Answer 24

Catalase
H2O2 –> H2O + O2

Dismutase
O2- + O2- –>H2O2 + H+ + O2

Question 25

Thioglutamate browth?

Answer 25

To separate the bacteria in a glass tube
Redox –> Resazonin - Pink or colorless

Top - Obligate
Near top - Microaeropiles
Throughout - Faculative
Bottom - Anaerobes