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1
Q

B) How much does an electron microscope magnify?

A

100,000 x

2
Q

Look over table 3.1

A

pg40

3
Q

D) How does a bright-field microscope work?

A

light passes through a specimen then through a sereis of lenses

4
Q

E) What is the defining characteristic(s) of a compound microscope?

A

multiple lenses

5
Q

1) What does a condenser lens do?

F) What is resolving power and what affects it? [Figure 3.2]

A

1- condenser lense- focuses light on specimin

Resolving power- how close two things can be to see then clearly. light/ na of condenser+na of objective

6
Q

G) What is the refractive index? [Figure 3.3]

A

How light is bent or travels through that stuff. Why we use emersion oil

7
Q

H) What is contrast?

A

is difference when looking at it.in comparison to others, that is why we stain

8
Q

J) How does a dark-field microscope work? [Figure 3.4]

A

dark field stop on end of condenser lense. works like light shining into dark room helps you see dust. cells viewed as bright objects on dark background

9
Q

H) How does a phase-contrast microscope work? [Figure 3.5]

A

makes denser material apear darker… does this by amplifying the differences of refractive index of different parts of a cell due to it’s density. uses special optial devices to do this

10
Q

How does a differential interference contrast microscope work? [Figure 3.6]

A

provides a 3d image. device seperates light into two beams that pass through a specimen and then recombine

11
Q

J) How does a fluorescence microscope work and, what is it used for? [Figure 3.7]

A

used to see cells that are naturally florescent. light doesn’t need to pass through the cells instead project a uv light onto the cells.

12
Q

K) How does a scanning laser microscope work? [Figure 3.7]

A

detailed interior view of intact cells. use a florecent stain or tag

13
Q

L) How does a confocal microscope work?

A

use a laser beam to illuminate a specific point on a vertivle plane of the specimin and uses mirrors to scan then a computer constructs a 3D image

14
Q

M) How does a multiphoton microscope work?

A

uses a lower energy light than the confocal microscope so you can get images of live cells

15
Q

N) How do electron microscopes differ from light microscopes?

A

use instead of light wave, uses electron waves. must be in a vacume or the air interferes with the electron waves.

16
Q

How does a transmission electron microscope work?

A

used to observed fine detail of cell structure. uses electrons to pass through cell.. the darker segments are denser and electrons do not pass through it. use thin sectioning , or freese fracturing. where you slice the cell to see the inside

17
Q

How does a cryo-electron microscopy work?

A

freeze the specimen and then they take different angles to form a 3d image

18
Q

Q) How does a scanning electron microscope work? [Figure3.11

A

surface details of a cell. coats the cells with the thin metal film and then electrons are released from the coated cells and the microscope picks up the raditation

19
Q

How does an atomic force microscope work?

A

compared to a stylus arm on record player that senses all the bumps on the exterior

20
Q

A) What is the first step when staining bacteria? [Figure 3.13]

A

spread specimin on slide

21
Q

B) What is the defining characteristic of a simple stain?

A

single dye is used

22
Q

C) What does a negative stain look like and how is it done?

A

dye that stains the background…. cell repels the neg charged stain

23
Q

D) What is a differential stain used for? What are the two most frequently used?

A

distinguish one group of cells from the other. Gram and acid fast stains

24
Q

1) How is a gram stain done? [Figure 3.14 and gram stain video]

A

q

25
Q

-What is the difference between a gram negative and a gram positive bacterium.

A

Gram pos- has the thick peptoglycogen membrane over the phospholipid
Gram neg- is 2 lipid layers with small peptogycogen in betweeen

26
Q

2) What is an acid fast stain used for and how is it done?

A

detect myobacterium which do not easily take up dies.
put red dye which is really powerful, or you heat it to melt the waxy . Then you apply the acid alchohol….the cells that retain the dye are acid fast cells. and then you add a blue dye as a countersain

27
Q

E) What does a capsule stain let you see? [Figure 3.16]

A

use a negative stain and the capsules (gel like outer layer, do not absorb the dye.

28
Q

F) What does an endospore stain let you see? How does it work? [Figure 3.17]

A

Dye with a malachite green and heat. Then rinse and add a counterstain to see the rest of the cell( baccilus and clostridium)

29
Q

G) How can you visualize flagella? [Figure 3.18]

A

add a flagella stain that coats the flagella making it thicker and more visible

30
Q

H) When is fluorescence used? [Figure 3.19]

A

q

31
Q

1) What is immunofluorescence?

A

uses an antibody to tag specific protiens with a florescent dye

32
Q

A) What shapes do bacteria come in and what are their names? [Figure 3.21]

A

-cocus = round
-rod /baccilus
-vibrio- like a macaroni noodle
-spirillium-
spriochete- like spirillium, but tighter

33
Q

B) What are the names for typical cell groupings? [Figure 3.22]

A

Chains, packets and groupings

34
Q

C) What are multicellular associations?

A

bacteria live/ work together. ie. group releases a slime that helps break down other organisms

35
Q

D) What are the structures of the prokaryotic cell? [Figure 3.23]

A
- Cell envelope
    Capsule
    Cell wall
   Cytoplasmic membrane
-cytoplasm
- nucleiod
36
Q

A) What is the cytoplasmic membrane? How is it’s structured? [Figure 3.24]

A

thin structure that defines the boundery of the cell and surrounds the cytoplasm.
composed of phospholipids and protiens

37
Q

B) What is the fluid mosaic model?

A

refers to the fact that the membrane protiens move around in the phospholipid bilayer

38
Q

C) What does being selectively permeable mean? [Figure 3.25]

A

It only allows certain things to pass through the membrane. usually only allowing sm gases, water, and hydrophobic molecules

39
Q

D) What are aquaporins?

A

“water gates” that let in water to the cell

40
Q

electron transport chain

A

in membrane takes the electons off hydrogens and pumps the hydrogen(protons) out of the cell creating a gradeint.. then cell allows them to come back in and the energy makes atp

41
Q

A) What mechanism allows things to enter the cell? [Figure 3.28 and Table 3.4]

A

transport protiens

42
Q

B) What is facilitated diffusion and how does it work? [Figure 3.29a and How Facilitated Diffusion Works video]

A

uses transport protien to move something down it’s concentration gradient

43
Q

C) What is active transport and what are the mechanisms? [Figure 3.29b]

A

Moves compounds against the concentration gradient.
2 mechanisms
-atp-ABC transport system uses atp these use specific binding protiens on outside of cell to gather and deliver molecules
-proton motive force-uses the movement of the protons to propel pumps to pump things out or come in with the flood of the protons

44
Q

D) What is group translocation and how is it done? [Figure 3.9c and Active transport by group translocation video]

A

transport process that as it bring it through the membrane chemically alters it- usually phosphorylating

45
Q

E) What is the process of secretion? [Figure 3.30]

A

signal sequence causes cell to secrete it…. during which it takes off teh sequence and the protien will fold into it’s functional shape

46
Q

1) How does a cell know which polypeptides to secrete?

A

the aa signal sequence

47
Q

1) What is peptidoglycan? What is its basic structure and where is it found? [Figure 3.31 and Peptidoglycan Biosynthesis video]

A

Found in cell walls. It is an alternating of two major subunits NAM n acetylmuramic
(Composed of tetrapeptide chains and link to adjacent glycan chains), and NAG n acetylglucosamine

48
Q

What are teichoic acids and where are they found? [Figure 3.32]

A

neg charged chains in gram pos cell walls that stick above the pept. layer and bind to cations. ribitol or glycerol phosphate that attatch to various sugars

49
Q

3) What kind of bacterium have lipopolysaccharides on it’s outer membrane? [Figure 3.33]
-

A

Gram neg cell wall outermost lipid layer. lps signals humans defense systems (endotoxin)

50
Q

-What are the two parts of the LPS molecule?

A

Lipid a- links to the other bilipid layer

Oantigen chain of sugar molecules on outermost part

51
Q

4) What are the functions of porins?

A

Specialized channels that allow many different molecules to pass

52
Q

B) What is periplasm and where is it found?

A

gel like substance in the periplasmic space betwwn cytoplamic membrane and outer membrane

53
Q

C) How does Penicillin work and what is it most effective against?

A

Penicillin: interferes with peptogylcan synthesis- better affects gram positive bacteria

54
Q

D) What is Lysozyme and what does it do?

A

breaks down molecules. is used in the lab to break down peptoglycan layer

55
Q

E) What is the reason behind why cells are either pink or purple after a gram stain?

A

purple -gram positive

56
Q

F) What type of bacteria lack a cell wall? [Figure 3.34]

A

Mycoplasma cytoplasmic membranes have sterols in it.

57
Q

G) What type of cell walls do Archaea have?

A

do not have peptoglycogen. they have pseudo pepto. and have slayer which are sheets of proteins

58
Q

What is the difference between a capsule and a slime layer? [Figure 3.35]

		1) What are they both composed of?
		2) What function do they serve?
A

Capsule:distinct and gelatinous layer around cell wall
Slime Layer: irregular gelatinous lauer
mainly composed of polysacharides like glycocalyx
act as adhesion so the cell can stick to other things
avoid host defense systems (phagocytosis)

59
Q

1) What are the flagella’s three basic parts? [Figure 3.37]

A

philament, hook, and basal body

60
Q

2) What type of flagella arrangements are there?

A

petrichous- all around

polar- 1 flagella at one end of cell

61
Q

B) What is the phenomenon known as chemotaxis? [Figure 3.38, 3.39 and Chemotaxis—ecol/ video]

A

bacteria sense a chemical and respond by moving in a certain direction.

62
Q

C) What are pili and what function do they have? [Figure 3.40]

A

allow cells to atatch to certain surfaces, and movement

63
Q

1) What are fimbriae and what do they do?

A

pilli that attatch to cells

64
Q

2) What type of pilus is used for DNA transfer?

A

sex pilus

65
Q

) What are plasmids?

A

circular supercoiled dna. smaller than the chromosome.

some code for production of enzymes that resist antibiotics

66
Q

C) What are ribosomes? What are the different types? [Figure 3.42]

A

involved in protien synthesis
Prokaryotic 70S
and
Eukaryotic 80s

67
Q

What are storage granules and what is their use? [Figure 3.43]

A

accumulation of polymers that cell will use later and so they store it in prep of replication

68
Q

E) What are gas vesicles and what is their function?

A

protien bound compartments that provide bouyance to the cell

69
Q

F) What are endospores? What is special about them? [Figure 3.44 and Bacterial Spore Formation]
?

A

Endospores released by cells that lack nutrients. Dormant cells produced by baccilus and clostridium. They are almost indestructable!

70
Q

1) When and how do they germinate?

A

?

71
Q

2) What is a vegetative cell?

A

one that multiplies

72
Q

3) What is the process of sporulation

A

cell senses starvation
dna is duplicated
and septum forms
larger compartment engulfs smaller forming a forespore in mother cell
Ppeptoglycan is laid around the forespore
mother cell is degraded and releases the endospore

73
Q

A) What is a plasma membrane, what function does it serve, and who has one?

A

Eukaryotic cells!

Typically a phospholipid bilayer

74
Q

C) What are the active and passive transport mechanisms of the eukaryotic cell?

A

q

75
Q

D) What is endocytosis and exocytosis? How is it done? [Figure 3.48]

A

endo- brings in. membrane invaginates then seals off

exo- kick out,

76
Q

E) How is secretion done in the eukaryotic cell?

A

same as eukaryotic

77
Q

) What type of ribosome does the eukaryotic cell have?

A

80s

78
Q

B) What is the cytoskeleton? What is it made of? [Figure 3.49]

A

Cytoskeleton frame work of a cell

made of actin filaments, microtubules and intermediate filaments

79
Q

C) What are flagella and cilia made of and how do they differ? [Figure 3.50]

A

made of microtubules!

80
Q

A) What is the nucleus? What is it composed of? What events take place there? [Figure 3.51]

A

Composed of nuclear envelope

  • 2 lipid bilayers (inner and outer membranes)
  • in the membranes are protiens that create pores

DNA wound in histones is there
Nuleos is where the rna is manufactured and is linear (opposite of inside prokaryotes)

81
Q

B) What is the function of mitochondria? What is it composed of? [Figure 3.52]

A

power house
2 lipid bilayers:
1 round and the other folded
contains dna ribosomes and other molecules

82
Q

1) What is endosymbiotic theory?

A

That eukaryotes evolved from prokayotes: founded based that the mitochandira divide in a similair fashion to prokaryotic cells.

83
Q

lysosomes? What process are they involved in?

A

autophagy ( digestion of uneeded cell components)

84
Q

G) What are peroxisomes?

A

detox the cell using o2 and help break down lipids

85
Q

C) What is the function of chloroplasts and where are they found? What are they made up of? [Figure 3.53]

A

in plants and algea. harvest sunlight to produce e