Brainscape's Knowledge GenomeTM

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


See full index

Microbio Exam 1- Lecture > Lecture 2: Microbial Cell Structure and Function Part 1 > Flashcards

Lecture 2: Microbial Cell Structure and Function Part 1 Flashcards

1
Q

Where do bacteria live?

A

Live in terrestrial and aquatic environments

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

How do bacteria reproduce?

A

Reproduce asexually via binary fission

How well did you know this?
1
Not at all
2
3
4
5
Perfectly
3
Q
  1. What is the size range for bacteria? 2. What is the “average” size?
A
  1. Size ranges from 0.3um (micrometers) to 100um 2. Average size is about 4um (size of E. coli)
How well did you know this?
1
Not at all
2
3
4
5
Perfectly
4
Q
  1. What is this genus?
  2. Is it a bacteria or a virus?
  3. What is unique about it/it’s energy source?
A
  1. Thiomargarita
  2. Bacteria
  3. It’s a chemolythotrope that uses sulfur for energy
How well did you know this?
1
Not at all
2
3
4
5
Perfectly
5
Q
  1. Some bacteria and many fungi form long filaments called?
  2. A network of these filaments is called?
A
  1. Hyphae
  2. Network of hyphae is called a mycelium
How well did you know this?
1
Not at all
2
3
4
5
Perfectly
6
Q

What is this?

****

A

Staphylococcus

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

What is this cell shape?

****

A

Bacillus (rods), chains of rods are streptobacillus

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

What is this cell shape?

********

A

Streptococcus

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

What is this cell shape? Rigid or flexible?

*****

A

Sprillum, rigid

How well did you know this?
1
Not at all
2
3
4
5
Perfectly
10
Q
  1. What is this cell shape? ****
  2. What disease is this?
A
  1. Vibrio (Curved Rod)
  2. Cohlera
How well did you know this?
1
Not at all
2
3
4
5
Perfectly
11
Q
  1. What is this cell shape?
  2. Is it rigid or flexible?
  3. What disease does this cause?
A
  1. Spirochete
  2. Flexible
  3. Lyme’s Disease
How well did you know this?
1
Not at all
2
3
4
5
Perfectly
12
Q
  1. What cell shape is this?
  2. What is the genus? ******
  3. What is unique/challenging about this genus?
A
  1. Tetrads
  2. Genus = Deinococcus ****
  3. Radiation resistant
How well did you know this?
1
Not at all
2
3
4
5
Perfectly
13
Q

What are these cell shapes?

A

Pleomorphic

Some round, some fork shaped, can change shapes under various conditions

Mycoplasma is an example.

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

What is cytoplasm?

A

Substance inside of cell which includes chromosomes, ribosomes and inclusions. Mostly water and highly concentrated

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

__________ and ____________ occur within the cytoplasm of a bacterial cell?

A

Transcription

and

Translation

occur here in a bacterial cell

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

RNA polymerase does what?

A

Transcribes DNA to mRNA

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

Ribsomes do what?

A

These structures translate mRNA into protein

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

In Bacteria and Archaea, transcription and translation occur simutaneously or at different times?

A

Occur simutanesouly in bacteria and archea

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

What is the nucleoid?

A

Region containing chromosomes

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

What are some characteristics of nucleoids?

A
  • closed, circular, DS DNA
  • typically 1 per cell
  • NOT membrane enclosed
  • some bacteria have more than 1 chromosome
  • some have linear chromosomes
How well did you know this?
1
Not at all
2
3
4
5
Perfectly
21
Q

What is a plasmid?

A

Small, closed ciricular loop of DNA

22
Q

What are characteristics of plasmids?

A
  • They exist and replicate independently of the chromosome
  • May carry genes that confer advantage
    • Conjugative plasmids
    • R plasmids (R= resistance)
23
Q

What are 4 purposes of the bacterial plasma membrane?

A
  1. Selectively permeable barrier
  2. Transport systems bring nutrients in
  3. Main site of energy production via the electron transport chain
  4. Signal transduction systems–sense and respond to environment
24
Q

Plasma membranes of eukaryotic cells are stablilized by cholesterols called

A

Sterols

Bacterial cell membranes don’t have sterols, but have sterol like molecules

25
Q

What are the serol-like (cholesterol) molecules in some bacterial cell membranes that help with stabilization?

A

Hopanoids

26
Q

Despide the lipid bilayer (type of bonds, head and tails, other things inside)

A

Lipids have flexibile ester bonds

Lipids are amphipathic

Polar ends (OUTSIDE) hydrophilic

Non polar tails are hydrophobic

Various proteins can be found within the membrane

27
Q

What’s the purpose of the bacterial cell wall and where is it?

A

Bacterial cell wall lies outside of the plasma membrane. The cell wall for Gram + bacteria is different than the cell wall for gram -

Functions

  • Gives the bacterial cell shape
  • Protection
    • toxic substances
    • osmotic lysis
      *
28
Q

How does osmosis affect bacterial cells? What can happen that’s bad?

What helps protect bacterial cells?

A

Cells are usually surrounded by relatively dilute solutions which means the concentration of a solute is greater inside the cell than out, so water is tempted to move in the cell.

The bacterial cell wall helps prevent osmotic lysis—-which is where osomosis causes the cell to burst due to the influx of water into the cell

29
Q

What color do gram + cells stain?

What about gram -?

A

Gram + stain PURPLE :)

Gram - stain pink

30
Q

Where is peptidoglycan found

A

Bacterial cell WALL

NOT in the membrane

31
Q

Describe the structure of peptidoglycan:

  1. Sugars
  2. Proteins
A
  • Peptidoglycan is an important component of cell walls in gram + and gram - cells.
  • It has two alternating sugar groups that form a polysaccharide (NAG + NAM).
    • The NAG and NAM sugars are connected by a B 1,4 glycosidic bond
  • Coming off of the NAM are cross-linked peptides of alternating D and L amino acids
32
Q

What is NAG?

A

N-acetylglucosamine

1 of the sugars in peptidoglycan

33
Q

What is NAM?

A

N-acetylmuramic acid

One of the alternating sugars in peptidoglcan. The cross linked peptides come off of the NAM molecule

34
Q

What type of bond connects NAG and NAM?

What enzyme breaks down that bond?

A

Connected by B 1,4 glycosidic bonds.

Lysozyme breaks down B 1,4 glycosidic bonds

35
Q

Describe the combination of peptides in peptidoglycan:

What are the two ways to combine?

A

The peptides of peptidoglycan are cross-linked

There are 2 types of cross-linking: direct and indirect

36
Q

What is the process that provides direct cross-linking of proteins within peptidoglycan?

A

Transpeptidation is the reaction where proteins in the peptidoglycan are cross linked

This provides strength

37
Q

What is used for indirect cross linking of the proteins in peptidoglycan?

A

Indirect cross linking uses peptide interbridges

38
Q

What is the structural feature found within the peptidoglycan of gram + cell walls?

A

Teichoic acid is polymers of glycerol or ribitol that provide stability in the peptidoglycan of gram POSITIVE cell walls

39
Q

Which type of bacteria has an outer membrane?

What are 4 things found in the outer membrane?

A

Gram - bacterial have outer membranes

Lipids, proteins and LPS (lipopolysacchardies), porins are found in the outer membrane

40
Q

What are porins?

A

proteins in the membrane that form channels for small molecules to go through

41
Q

What type of cell is this?

What are the areas labelled?

A

Gram negative cell

42
Q

What type of cell is this?

What are the areas that are crossed out?

A
43
Q

What molecule is this?
What type of cell is it found in?

Where is it found in that cell?

What are the 3 components?

A

LPS: lipopolysaccharide found in the outer membrane of gram - bacteria

Comprised of the:

  1. O side chain
  2. Core polysaccharide
  3. Lipid A
44
Q

What are 4 purposes of LPS?

A
  1. Protection from host defenses
    1. O antigens vary
  2. Attachment
  3. Stability
  4. Toxin
45
Q

When LPS acts as a toxin, it is called what?

A

endotoxin

46
Q

What are 3 types of layers that can be found outside of the cell wall for gram + and gram - bacteria as well as archaea?

A
  1. Capsules
  2. Slime layers
  3. S layers
47
Q

What are capsules made from?

Describe them

A

Polysaccharides

Organized, not easily removed

48
Q

What are slime layers made from?

Describe them

A

Polysaccharides

-Diffuse, unorganized, easily removed

49
Q

What are S layers made from?

Describe them

A

Proteins!

Organized. Help with structure and stability

50
Q

What do layers (S layers, capsules, and slime layers) help with?

A
  • Attachment
  • Protection from
    • Chemicals
    • Harsh environments
    • Bacterial viruses (bacteriophages)
    • Host immune response
      • ie. slime layers made it hard for host cell macrophages to consume them
51
Q

What bacteria is this?

A

Neisseria meningitidis

Microbio Exam 1- Lecture (6 decks)

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