Brainscape's Knowledge GenomeTM

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


See full index

MicroBio > Test 3 Chapter 9 Study Guide > Flashcards

Test 3 Chapter 9 Study Guide Flashcards

1
Q

Daughter cells

A

Two completely identical cells formed as a result of binary fission

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

Binary Fission

A

Most common method of prokaryotic division. Replicates DNA. Center constricts forming two daughter cells

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

FtsZ Protein

A

Directs cytokinesis and cell division in prokaryotic cells

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

First step of Binary fission

A

FtsZ forms a Z Ring on the cytoplasmic membrane

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

Second step of Binary fission

A

Z ring is anchored by FtsZ-binding proteins defining the division plane

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

Third step of Binary Fission

A

Additonal proteins added to z ring to form a divisome

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

Final step of Binary Fission

A

Divisome leads to peptidoglycan production and septum formation

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

Septum Formation

A

Forms new cell wall between the daughter cells at the end of binary fission

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

Generation (doubling) time

A

Time it takes for the population to double through binary fission

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

Formula for generation time

A

Number of cells = Starting cells x 2^number of generations

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

Bacterial Growth Curve

A

Growth patter of microorganisms in a closed culture NO NUTRIENTS ADDED OR WASTES REMOVED

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

Lag Phase

A

Immediately after adding bacteria to culture. No increase in number of living bacteria. Bottom of the curve.

How well did you know this?
1
Not at all
2
3
4
5
Perfectly
12
Q

Log Phase

A

Exponential increase in number of bacteria cells. Rise on graph. Constant growth. IDEAL STAGE FOR RESEATCH AND MOST SUSCEPTIBLE TO ANTIMICROBIALS/DISINFECTANTS.

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

Stationary phase

A

When New cells = dying cells. Plateau on graph. Endospores may form

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

Death Phase

A

Dying cells > new cells. Down slope of graph. Persisters may remain.

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

CFU/mL – if count 50 colonies on 1:10,000 dilution (10^-4)

A

CFU/mL = 50 * 10 * 10,000 = 5,000,000 = 5.00 x 10^-6 CFU/mL

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

Serial Dilutions

A

1mL from original culture, added to 9 mL broth - makes a 1:10 dilution

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

Biofilm

A

Ecosystems of bacteria. Many different bacteria hanging out.

How well did you know this?
1
Not at all
2
3
4
5
Perfectly
18
Q

Bacteria Perks of Biofilm

A

Highly structured communities, selective advantage to bacteria. Resist antimicrobial, resource sharing, effective waste removal.

How well did you know this?
1
Not at all
2
3
4
5
Perfectly
19
Q

Biofilm Structure

A

Embedded in a matrix with water channels interspersed. Allows nutrient, waste, gas movemement.

How well did you know this?
1
Not at all
2
3
4
5
Perfectly
20
Q

Matrix of extracellular polymeric substances (EPS)

A

Polysaccharides and other macromolecules as a gel-like substance that holds biofilm together. Gives structure and integrity.

How well did you know this?
1
Not at all
2
3
4
5
Perfectly
21
Q

Quorum Sensing

A

Cells coordinate activity in response to environment.

How well did you know this?
1
Not at all
2
3
4
5
Perfectly
22
Q

Autoinducers

A

Communication molecules involved in Quorum Sensing

How well did you know this?
1
Not at all
2
3
4
5
Perfectly
23
Q

Great Oxygenation Event

A

Early atmosphere was anoxic (no oxygen) Cyanobacteria increased oxygen in atmosphere killing most anaerobes.

How well did you know this?
1
Not at all
2
3
4
5
Perfectly
24
Q

Reactive Oxygen Species (ROS)

A

By products of aerobic cellular respiration. Powerful redox reactions.

How well did you know this?
1
Not at all
2
3
4
5
Perfectly
25
Q

Anaerobic ecosystems

A

Oxygen free environments - Deep in Earth’s crust, Marshes, Bogs, Sewers, in the body.

26
Q

Obligate Aerobe

A

Needs oxygen to survive. Mycobacterium tuberculosis

27
Q

Obligate Anaerobe

A

Oxygen kills them. Lack enzymes to inactivate ROS. Bacteroides spp.

28
Q

Facultative Anaerobe

A

Aerobic bacteria, but can survive without oxygen. Grows best with oxygen. Staphylococci spp.

29
Q

Aerotolerant Anaerobe

A

Tolerate oxygen, some enzymes to deal with ROS. Lactobacilli

30
Q

Microaerophile

A

Obligate Aerobes, but require a very specific amount of oxygen. Around 1-10% oxygen. Campylobacter jejuni

31
Q

Obligate Aerobe in a Thioglycolate Medium (FTM test).

A

Bacterial cells all at the top of the tube, need oxygen

32
Q

Obligate anaerobes in a Thioglycolate Medium (FTM test).

A

Bacterial cells all at the bottom of the tube, killed by oxygen.

33
Q

Facultative Anaerobes in a Thioglycolate Medium (FTM test).

A

Bacterial cells mostly at the top some spread throughout tube.

34
Q

Aerotolerant Anaerobes Thioglycolate Medium (FTM test).

A

Bacterial cells spread throughout the tube.

35
Q

Microaerophile in a Thioglycolate Medium (FTM test).

A

Bacterial cells close to the top but not on top.

36
Q

Preoxidase

A

Breaks down hydrogen peroxide and turns it into water. Limits damage to membrane lipids

37
Q

Superoxide dismutase (SOD)

A

Breaks down superoxide anions generated by aerobic metabolism

38
Q

Catalase

A

Breaks down two hydrogen peroxide into 2 water and some oxygen

39
Q

pH and microbial growth at High pH

A

Hydrogen bonds between DNA strands are broken and lipids are hydrolyzed. pH imbalances denature proteins

40
Q

Optimum pH

A

Most favorable pH for organism growth

41
Q

Minimum pH

A

Lowest pH an organism can tolerate.

42
Q

Maximum pH

A

Highest pH an organism can tolerate,

43
Q

Neutrophile

A

Optimum growth range around pH of 7 (6-8)
Location: Neutral environments.

44
Q

Acidophile

A

Have pumps to actively transport H+ out of the cell. Optimum Growth <5.5
Used for food fermentation.
Location: Sauerkraut, pickles.

45
Q

Alkalinophile

A

Lipid and protein modifications. Optimum growth 8.0-10.5.
Location: soda lakes
Basic enviornments.

46
Q

Optimum Temp

A

temp where growth rates are highest

47
Q

Minimum temp

A

Lowest temperature where bacteria can divide

48
Q

Maximum temp

A

Highest temperature at which growth can occur

49
Q

Psychrophile

A

can grow at 0C but optimum is closer to 15C and rarely survive above 20C

50
Q

Psychrotrophs

A

4C - 25C

51
Q

Mesophile

A

Moderate Temperature between 20C - 45C

52
Q

Thermophile

A

Like it hot 50C - 80C

53
Q

Hyperthermophile

A

Really Hot 80C-110C

54
Q

What happens to bacteria in the cold

A

Membranes lose fluidity (become stiff & hard). ice crystals form. Proteins denature.

55
Q

Psychrophiles and Psychrotrophs (defenses)

A

Increased hydrophobic R groups in protein

Antifreeze proteins

Increase in unsaturated fatty acids – Harder to freeze because so fluid

56
Q

What happens to bacteria in the Hot

A

Membranes become too fluid (melt). Proteins denature. Nucleic Acids Denature.

57
Q

Thermophiles and hyperthermophiles (Defenses)

A

Increase in saturated fatty acids – harder to melt cause solid

Higher GC content in DNA

Additional bonds to allow protein stability

58
Q

Hypotonic

A

pressure inside the cell greater than outside.

Net water movement into the cell

59
Q

Isotonic

A

Equal pressure inside and outside the cell

Net water movement back and forth equal

60
Q

Hypertonic

A

Pressure outside the cell greater than inside, net movement out of the cell.

Halo likes salt

Halotolerant organisms

Halophiles

61
Q

Halotolerant organisms

A

Tolerate high salt, not super high salt

62
Q

Halophiles

A

require high salt environment.

Dead Sea

63
Q

Barophile

A

Require high pressure

MicroBio (17 decks)

Brainscape helps you reach your goals faster, through stronger study habits.
© 2025 Bold Learning Solutions. Terms and Conditions