Lecture 5B - Functional Anatomy of Bacterial Cells (Internal to Cell Wall) Flashcards
1
Q
Structures Internal to the Cell wall
A
- plasma (cytoplasmic) membrane
- cytoplasm
- nuclear area (nucleoid)
- plasmids
- ribosomes
- inclusions
- endospores
2
Q
- thin structure inside of cell wall that surrounds cytoplasm
- phospholipid bilayer with proteins
- lack sterols and are less rigid than eukaryotic membranes
A
plasma (cytoplasmic) membrane
3
Q
phospholipid bilayers with proteins
A
fluid mosaic model
4
Q
Two parts of phospholipid bilayer with proteins
A
- integral membrane proteins
- peripheral membrane proteins
5
Q
penetrate membrane completely
A
integral membrane proteins
6
Q
on inner or outer membrane surface
A
peripheral membrane proteins
7
Q
exception of microorganisms that lack sterols and are less rigid than eukaryotic membrane
A
Mycoplasmas
8
Q
functions of the plasma membrane
A
- selective barrier
- nutrient breakdown and energy (ATP) production
- synthesis of cell wall components
- assists DNA replication
- site of photosynthesis
- secretes proteins
- contains bases of flagella
- respons to chemical substances in environment
9
Q
regulates passage of materials in and out of cell
A
selective barrier
10
Q
plasma membrane are impermeable to what
A
- large proteins
- ions
- most polar molecules
11
Q
plasma membrane are permeable to what
A
- water
- oxygen
- carbon dioxide
- some simple sugar
- small nonpolar substances
12
Q
membrane extensions of photosynthetic bacteria
A
thylakoids
13
Q
examples of antimicrobial agents that damage the integrity of plasma membrane
A
- alcohols
- quaternary ammonium compounds
- antibiotics (polymyxins)
14
Q
Two types of movement of materials across membranes
A
- passive process
- active process
15
Q
- substances move spontaneously from are of high concentration to low concentrations
- do not require energy expenditure (ATP)
A
passive transport process
16
Q
Different passive transport processes
A
- simple diffusion
- facilitated diffusion
- osmosis
17
Q
net movement of molecules or ions from an area of high concentration to low concentration
A
simple diffusion
18
Q
net movement stops when molecules are evenly distributed
A
equilibrium
19
Q
simple diffusion is used by cells to transport what
A
small molecules (oxygen, carbon dioxide)
20
Q
net movement of molecules or ions from an area of high concentration to low concentration with the help of carrier proteins
A
facilitated diffusion
21
Q
facilitated diffusion is by what
A
carrier proteins
22
Q
may be used to break down large substances vefore they can be moved ito cell by facilitated diffusion
A
extracellular enzymes
23
Q
net movement of water (solvent) across a semipermeable membrane from are of high concentration to low concentration of water
A
osmosis
24
Q
pressure required to prevent the movement of pure water into solution
A
osmotic pressure
25
Three different types of osmotic solutions
1. isotonic
2. hypotonic
3. hypertonic
26
concentration of solutes and water are equal on both sides of cell membrane
isotonic
27
solute concentration is lower outside the cell
hypotonic
28
solute concentration is higher outside the cell
hypertonic
29
result of isotonic
no net movement of water
30
result of hypotonic
net movement of water into the cell
31
result of hypertonic
net movement of water out of cell
32
- substances are concentrated, moved from an area of low concentration to high concentration
- require energy expenditure (ATP)
active process
33
different active processes
1. active tranport
2. group translocation
34
requires carrier proteins or pumps in plasma membrane
active transport
35
- similar to active transport, but substance tranposrted is chemically altered during process
- after modification, substance can't leave the cell
group translocation
36
phosphorlyated during group transloaction in bacterial cells
glucose
37
does not occur in procaryotic cells
endocytosis (phagocytosis, pinocytosis, etc.)
38
- substance inside the cell membrane
- contains 80% water, proteins, carbohydrates, lipids, inorganic ions, low molecular weight components
cytoplasm
39
what does the cytoplasm contain
1. 80% water
2. proteins
3. carbohydrates
4. lipids
5. inorganic ions
6. low molecular weight components
40
what does the cytoplasm lack
- cytoskeleton
- cytoplasmic streaming
41
contains a single chromosome, long circular molecule of double stranded DNA
nuclear area (nucleoid)
42
intracellular volume that the nuclear are may occupy
20%
43
- extrachromosomal component
- small, circular, double stranded DNA molecules
- found in many bacterial cells in addition to chromosomal DNA
plasmids
44
plasmids may contain how many genes
- 5 to 100 genes
- not essential for survival
45
genes in plasmid
- antibiotic resistance genes
- toxins
46
- site of protein synthesis
- found in all cells
ribosomes
47
what is the ribosome made up of
- proteins
- ribosomal RNA (rRNA)
48
prokaryotic ribosomes are smaller and less dense than eukaryotic ribosomes
prokaryotes: 70S
eukaryotes: 80S
49
two subunits of prokaryotic ribosomes
- small subunit
- large subunit
50
small subunit of prokaryotic ribosomes
30S
51
large subunit of prokaryotic ribosomes
50S
52
small subunit of eukaryotic ribosomes
40S
53
large subunit of eukaryotic ribosomes
60S
54
how do several antibiotic work in prokaryotic ribosomes
inhibit protein synthesis
55
- reserved deposits in the cytoplasm
- not found in all cell types
inclusions
56
different types of inclusions
1. metachromatic granules
2. polysaccharide granules
3. lipid inclusions
4. sulfur granules
5. carboxysomes
6. gas vacuoles
7. magnetosomes
57
- contain inorganic phosphate that can be used in the synthesis of ATP
- stain red with blue dyes
- found in bacteria, algae, protozoa, and fungi
metachromatic granules
58
what do metachromatic granules contain
inorganic phosphate
59
stain of metachromatic granules
stain red with blue dyes
60
where can metachromatic granules be found
- bacteria
- algae
- protozoa
- fungi
61
causative agent of diphtheria
_Corynebacterium_ _diphtheriae_
62
- contain glycogen and starch
- stain blue or reddish brown with iodine
polysaccharide granules
63
stain of polysaccharide granules
- blue (starch)
- reddish brown (glycogen)
64
- contain lipids
- detected with fat soluble dyes
lipid inclusions
65
how are lipid inclusions detected
with fat soluble dyes
66
- contain sulfur and sulfur containing compounds
- sulfur bacteria obtain energy by oxidizing sulfur and its compounds
sulfur granules
67
what do sulfur granules contain
- sulfur
- sulfur containing compounds
68
sulfur bacteria
_Thiobacillus_
69
- contain enzyme ribulose 1,5-diphosphate carboxylase (RuBisCo), necessary for carbon fixation during photosynthesis
- found in nitrifying bacteria, cyanobacteria, and thiobacilli
carboxysomes
70
what do carboxysomes contain
ribulose 1,5-bisphosphate carboxylase
71
where are carboxysomes found
- nitrifying bacteria
- cyanobacteria
- thiobacilli
72
- hollow cavities found in many aquatic bacteria
- contain individual gas vesicles, hollow cylinders coverd by protein
- used to regulat buoyancy so cells can remain at appropriate water depth
gas vacuoles
73
function of gas vacuole
regulate buoyancy so cells remain at appropriate water depth
74
- contain iron oxide (Fe2O3) which acts like magnet
- formed by several aquatic gram-negative bacteria
- enable bacteria to respond to magnetic fields (magnetotaxis)
magnetosomes
75
what do magnetosomes contain
iron oxide (Fe2O3)
76
who forms magnetosomes
several aquatic gram-negative bacteria
77
respond to magnetic fields
magnetotaxis
78
magnetotaxis allows bacteria to what
- swim towards North and South poles
- swim downwards towards sediments
79
magnetosomes may help the decomposition of what
hydrogen peroxide
80
how are magnetosomes used industrially
make magnetic audio tapes
81
- specialized "resting" cells formed by certain Gram-positive bacteria
- highly durable dehydrated cells with thick cell walls and additional layers
- can survive extreme temperature, disinfectants, acids, bases, lack of water, toxic chemicals, and radiation
- for survival
endospore
82
Gram-positive bacteria that form endospore
1. Genus _Bacillus_
2. Genus _Clostridium_
83
endospores of some thermophilic bacteria can survive how many hours of boiling
19 hours
84
what can endospores survive
1. extreme temperatures
2. disinfectants
3. acids
4. bases
5. lack of water
6. toxic chemicals
7. radiation
85
formation of endospore
sporulation
86
process of sporulation
1. DNA isolated by spore septum
2. spore septum becomes forespore
3. peptidoglycan forms between membranes of forespore
4. spore coat forms
5. maturation
87
ingrowth of plasma membrane
spore septum
88
spore septum becomes a double-layered membrane that surrounds chormosome and cytoplasm
forespore
89
- thick layer of protein around the outer membrane
- makes endospore resistant to many harsh chemicals
spore coat
90
cell wall ruptures, endospore is released
maturation
91
unlike vegetative cells, endospore do not what
carry out metabolic reactions
92
how long can endospores last
thousands of years
93
- endospore returns to its vegetative state
- usually occurs when environmental conditions become more favorable
- triggered by physical or chemical damage to spore coat
germination
94
endospore cycle
vegetative cell (metabolically active) --> sporulation --> endospore (not metabolically active) --> germination --> vegetative cell (metabolically active)
