Brainscape's Knowledge GenomeTM

Browse over 1 million classes created by top students, professors, publishers, and experts.


See full index

Microbiology > Bacterial Physiology And Metabolism > Flashcards

Bacterial Physiology And Metabolism Flashcards

You may prefer our related Brainscape-certified flashcards:
Biology 101 flashcards
1
Q

Bacterial physiology and metabolism can be

A 
Bacterial metabolism 
Growth requirements 
Bacterial enzymes
Bacterial pigments and toxins
Bacterial growth curve
How well did you know this?
1
Not at all
2
3
4
5
Perfectly
2
Q

Bacterial metabolism definition

A

Metabolism means the chemical processes that occur within a cell. Bacteria needs energy to grow. Energy is brought through respiration, photosynthesis or fermentation

How well did you know this?
1
Not at all
2
3
4
5
Perfectly
3
Q

Respiration definition and pathway

A

Respiration is an energy yielding process in which oxidation is followed by reduction.
Glucose in the cell - 2 hydrogen atoms gives gluconate
Gluconate + carbon dioxide + 2 hydrogen + Energy gives hydrogen peroxide
Catalase enzyme converts hydrogen peroxide to water and oxygen

How well did you know this?
1
Not at all
2
3
4
5
Perfectly
4
Q

In aerobic organisms, the ultimate electron acceptor is ……… because they have ……….

A

oxygen …………………… peroxidase enzyme

How well did you know this?
1
Not at all
2
3
4
5
Perfectly
5
Q

In anaerobic organisms, the ultimate electron acceptor is …… and converted to ……

A

Nitrate or sulphate ……………………. Nitrite or sulfite

How well did you know this?
1
Not at all
2
3
4
5
Perfectly
6
Q

Main elements needed for bacterial nutrition

A

Carbon and nitrogen

How well did you know this?
1
Not at all
2
3
4
5
Perfectly
7
Q

Autotrophs definition and examples

A

Bacteria can assimilate carbon and nitrogen from simple inorganic sources
Utilize CO2 and ammonium salts
Many saprophytic bacteria

How well did you know this?
1
Not at all
2
3
4
5
Perfectly
8
Q

Heterotrophs definition and examples

A

Require pre-formed sources of nutrition
Glucose and amino acids
Most pathogenic bacteria are examples

How well did you know this?
1
Not at all
2
3
4
5
Perfectly
9
Q

Gaseous requirements of bacteria

A

All bacteria need carbon dioxide to grow. Some depend on oxygen too

How well did you know this?
1
Not at all
2
3
4
5
Perfectly
10
Q

According to bacterial need for oxygen, bacteria can be divide to

A

Obligatory aerobes
Obligatory anaerobes
Aerobe facultative anaerobe
Micro aerophilic

How well did you know this?
1
Not at all
2
3
4
5
Perfectly
11
Q

According to the need of carbon dioxide, bacteria can be divided to

A
  • bacteria that grow normally in 0.04% carbon dioxide concentration
  • bacteria that need 5-10% carbon dioxide concentration (Capnophilic bacteria)
How well did you know this?
1
Not at all
2
3
4
5
Perfectly
12
Q

Capnophilic bacteria examples

A

Pneumococci
Gonococci
Brucella abortus

How well did you know this?
1
Not at all
2
3
4
5
Perfectly
13
Q

Micro aerophilic bacteria definition and examples

A

Grow best in presence of a trace of O2 (5%) and often prefer high concentration of CO2
Ex: Campylobacter

How well did you know this?
1
Not at all
2
3
4
5
Perfectly
14
Q

Aerobe facultative anaerobes definition and examples

A

Grow well in the presence of O2 and in its absence

Ex: Most pathogenic bacteria like Staphylococcus and E.coli

How well did you know this?
1
Not at all
2
3
4
5
Perfectly
15
Q

Obligatory anaerobes definition and examples

A

Grow only in absence of O2

Ex: Clostridium

How well did you know this?
1
Not at all
2
3
4
5
Perfectly
16
Q

Obligatory aerobes definition and examples

A

Grow only in presence of O2 (21%)

Ex: Mycobacterium tuberculosis and pseudomonas

How well did you know this?
1
Not at all
2
3
4
5
Perfectly
17
Q

Moisture effect on bacteria

A 
Drying is dangerous for many bacteria eg gonococci but some bacteria can survive dry places like:
T.b
Bacillus 
Spores
Clostridium
18
Q

Optimum temperature for bacterial growth

A

37 degrees

19
Q

Optimum pH for bacteria (neutral, acidic and alkaline)

A

Most pathogenic bacteria can grow at pH of 7.5 with a range of 7.2 to 7.6
Some bacteria prefer acidic media like Lactobacilli
Some bacteria prefer alkaline media like Vibro cholera

20
Q

Bacterial enzymes definition

A

Enzymes are biological catalysts which initiate and accelerate chemical reactions without themselves being changed.

21
Q

Types of bacterial enzymes

A

Can be:

  • Constitutive enzymes
  • Inducible enzymes
22
Q

Constitutive enzymes definition and examples

A

They are enzymes that are synthesized irrespective of the environmental conditions
Essential for fundamental metabolic pathways and growth of the bacteria
Like respiratory enzymes

23
Q

Inducible enzymes definition and examples

A

They are enzymes produced only in the presence of an inducer

Eg proteolytic enzymes

24
Q

Bacterial pigments types

A
  • endopigment

- exopigment

25
Q

Endopigments characteristics and examples

A

Non-diffusible.
Best demonstrated when the organism is grown on the surface of solid media.
Color appears within the colonies
e.g. golden yellow pigment of staph. aureus

26
Q

Exopigments characteristics and examples

A

Soluble or diffusible to the surrounding media
Colonies do not change color
e.g. Pseudomonas aeruginosa produce many types of pigments e.g. (pyocyanin and pyoverdin pigments) which turn the medium greenish(-blue).

27
Q

Factors affecting pigment production

A

Pigment production is better in aerobic conditions and room temperature

28
Q

Functions of the pigments

A

Help in identifying the bacteria

29
Q

Bacterial toxins definition

A

They are highly poisonous substances produced by certain bacterial species and lead to tissue damage

30
Q

Types of bacterial toxins

A

Endotoxin

Exotoxin

31
Q

Bacterial growth curve definition and how is it represented graphically

A

The definitive course of bacterial growth when cultivated in vitro in suitable medium and incubated at suitable temperature
Represented graphically by plotting the log of number of bacteria against the time in hours

32
Q

Bacterial growth curve phases

A

Lag phase
Log phase
Stationary phase
Decline phase

33
Q

Endotoxins properties and examples

DHN FATS

A 
Diffusability: Non-diffuasble
Heating: Stable
Nature: Lipopolysaccharide produced only by gram -ve bacteria as they have Lipid A
Formaline effect: NOt detoxified
Antigenicity: Poor
Toxicity: Low
Specificity: Non-specific, generalised action 
Examples: Salmonella Typhi
34
Q

Exotoxin properties and examples

DHN FATS

A

Diffusability: Diffusable
Heating: Destroyed
Nature: Protein in nature mainly secreted by grame +ve bacteria but can be secreted by Gram -ve
Formaline effect: Converted to toxoid
Antigenicity: Strong
Toxicity: High
Specificity: Selective action
Examples: In gram +ve like: Clostrodium tetani and C.diphtheria
In Gram -ve like: Vibro cholera

35
Q

Factors affecting the length of the lag phase:

A

1- The nature of the organism (E.coli has short lag phase while T.B has long lag phase)
2- Size of the inoculum: The bigger, the shorter the phase
3- Stage from which the inoculum was taken: if taken from the log phase, the lag phase will be slow
4- Suitability of the medium: The more suitable the medium the shorter the lag phase

36
Q

Lag phase corresponds with:

A

Incubation period of the disease

37
Q

Log phase corresponds with:

A

Acute phase of the disease

38
Q

Stationary phase corresponds with:

A

Chronic phase of the disease

39
Q

Decline phase corresponds with:

A

Convalescent phase ends with complete cure

40
Q

Sample taken from specimen and grown on a plate?

A

Culture

41
Q

Sample taken from a plate to be grown on a second plate?

A

Sub-culture

Microbiology (3 decks)

Brainscape helps you reach your goals faster, through stronger study habits.
© 2024 Bold Learning Solutions. Terms and Conditions