Cell structures and metabolism Flashcards
1
Q
organisms with NO distinct nuclear compartment to house their DNA
A
prokaryotic
2
Q
2 major classes of prokaryotic organisms
A
bacteria (eubacteria)
archaea
3
Q
3 major divisions of the living world
A
bacteria (eubacteria)
archaea (archabacteria)
eukaryotes
4
Q
organisms that house their DNA in a distinct, sub-cellular compartment (nucleus)
A
eukaryotic
5
Q
Is bacteria single or multi celled?
A
single
6
Q
Is archaea single or multi celled?
A
single
7
Q
Are eukaryotes single or multi celled?
A
mostly multi
yeast is single-celled
8
Q
complex, organized, multi-celled organisms with plasma membranes, membrane-bound organelles, DNA, RNA, ribosomes
A
eukaryotes
9
Q
this type of cell has genetic information (DNA) that is stored as chromosomes in membrane-bound nucleus
A
eukaryotic cells
10
Q
single-celled organisms; simple; contents are part of cytoplasm, not separated by membrane
A
prokaryotic cells
11
Q
organelle with selective barrier and enables cells to maintain integrity to function as a coordination chemical system
A
plasma membrane
12
Q
organelle that is the “store-house” of genetic information
A
nucleus
13
Q
lipid and protein biosynthesis and intracellular Ca2+ store (organelle)
A
ER
14
Q
membrane bound ribosomes which allows for co-translational translocation of protein peptides chains into the ER concomitant with protein synthesis (organelle)
A
Rough Er
15
Q
regions of ER that lack ribosomes (organelle)
A
Smooth ER
16
Q
regions of smooth ER from which transport vesicles bud off and carry newly synthesizes proteins and lipids to the Golgi (organelle)
A
Transitional ER
17
Q
In cells that specialize in lipid metabolism, the synthesis occurs in the __ ER.
A
smooth
18
Q
In muscle cells, the expanded smooth ER is specialized for Ca2+ storage and is called the ____.
A
sarcoplasmic reticulum
19
Q
major site of carbohydrate synthesis, sorting, and dispatching of products made in the ER
A
Golgi
20
Q
Energy metabolism (oxidative phosphorylation and Krebs cycle)
A
mitochondria
also has distinct mitochondrial DNA genome separate from nuclear DNA
21
Q
site of intracellular digestion of macromolecules
very heterogeneous in terms of morphology
hydrolytic enzymes in these are all acid hydrolases
A
lysosomes
22
Q
organelles in eukaryotic cells
A
plasma membrane
nucleus
ER (rough and smooth
23
Q
prokaryotes: cell membrane? nucleus? chromosomes? ER? vesicles? Golgi? Mitochondria? cytoskeleton? ribosomes? size?
A
yes no 1 (not true chromo) no yes no no yes/no yes (smaller) 1-10 microns
24
Q
eukaryotes: cell membrane? nucleus? chromosomes? ER? vesicles? Golgi? Mitochondria? cytoskeleton? ribosomes? size?
A
yes yes many yes yes yes yes yes yes (larger) 10-100 microns
25
key structures in bacteria
fimbriae (or pili)
flagella
LPS
capsule
26
function of fimbriae (pili)
attachement to surfaces
27
function of flagella
motility
28
function of lipopolysaccharides (LPS)
activate inflammatory response
29
function of capsule
may play role in dental caries
30
Which bacterial cell wall appears blue/purple?
Gram positive
31
Which bacterial cell wall appears pink/red?
Gram negative
32
What causes the gram positive bacteria to appear purple/blue?
thick peptidoglycan layer (cell wall)
| prevents crystal violet from being washed out
33
Which bacterial cell wall has an inner and outer membrane?
Gram negative
| gram + has an inner membrane but no outer membrane
34
Teichoic acids are found on gram positive or negative bacterial cell walls?
positive
35
LPS is found on the outer membrane of gram positive or negative bacterial cell walls?
negative
36
What is the enzyme that is responsible for the crosslinking in peptidoglycan?
transpeptidase
37
Transpeptidase is inhibited by which antibiotic?
ampicillin
38
Peptidoglycan is comprised of chains of alternating ___ and ___ sugars.
N-acetylmuramic acid (NAM)
| N-acetylglucosamine (NAG)
39
Peptidoglycan chains are cross-linked by ____.
oligopeptides
40
What does a eukaryotic cell membrane consist of?
lipid bilayer
| proteins (ex: transmembrane, inner and outer proteins)
41
has membrane bound organelles
site of oxidative phosphorylation and major ATP production within the cell
contain small, circular genome
mitochondria
42
Where in the mitochondria does oxidative phosphorylation occur?
inner mitochondrial membrane
43
Where does glycolysis occur?
cytoplasm
44
What does glycolysis generate in the cytoplasm?
pyruvate
45
In anaerobic conditions, pyruvate will be converted into ___.
lactic acid
46
In aerobic conditions, pyruvate will enter the ___.
krebs cycle
47
Where does the krebs cycle occur?
mitochondrial matrix
48
What needs to be transported into the mitochondrial matrix for the krebs cycle?
pyruvate
49
How does pyruvate cross the outer mitochondrial membrane?
voltage-gated anion channels
50
What is pyruvate converted into in the mitochondrial matrix?
Acetyl-CoA
51
What converts pyruvate into acetyl-CoA?
pyruvate dehydrogenase complex
52
Acetyl-CoA transfers its acetyl group to ___ to form ___ which begins the Krebs cycle.
oxaloacetate
| citrate
53
What is oxidative phosphorylation?
ADP--> ATP
54
What is the ETC?
NADH releases high energy electrons to form NAD+ and H+; electrons then drive process of pumping hydrogen ions (protons) from matrix to intermembrane space
55
What brings H+ back into matrix from the intermembrane space to produce ATP from ADP?
ATP synthase
56
What are the two processes dealing with the Krebs cycle and respiration?
ETC
| oxidative phosphorylation
57
In oxidative phosphorylation, each H+ that is pumped through the channel can generate __ molecule of ___.
1
| ATP
58
What is a better source of fuel: glucose or fatty acid? why?
fatty acid
| generate more NADH (31>8)
59
What is the net yield of glycolysis in terms of ATP and NADH?
2 ATP
| 2 NADH
60
How many ATP, NADH, and FADH2 does the citric acid cycle produce?
2 ATP
8 NADH
2 FADH2
61
A molecule of glucose can produce how many net ATP molecules?
30-32
62
What is a cooperating community of microorganisms within a matrix that is attached to a surface?
biofilms
63
Where do biofilms develop?
any fluid-filled environment containing microorganisms that are subjected to stress or fluid flow
64
Where are dental biofilms found?
tooth surfaces
| mucosal surfaces of the oral cavity
65
What is formed on a tooth immediately even after brushing?
pellicle
66
What attaches to a pellicle on the tooth?
largely gram + cocci and rods (seconds)
67
What does the pellicle form from?
proteins in the salvia or GCF
68
What is the function of the pellicle?
serves as a conditioning film for attachment of the initial colonizing bacteria
69
How do bacteria within micro-colonies communicate with each other?
chemical signals
70
What is the purpose of micro-colonies being porous?
have fluid channels that allow for the movement of nutrients, waste products, metabolites, enzymes, and O2
71
Cariogenic bacteria produce extracellular polysaccharides from ___.
sucrose
72
What makes up sucrose?
glucose
| fructose
73
Glucose can be built into homopolymers of glucose called ___.
glucans
(mutan --> water insoluble)
(dextran --> water-soluble)
74
Fructose can be built into homopolymers consisting of beta 1,2 and beta 2,6 linkages called ___.
fructans
75
What is the function of the extracellular polysaccharides from sucrose?
nutritional source for bacteria which supports further adhesion and subsequent accumulation of plaque
76
Sucrose is (highly/poorly) soluble and diffuses (rapidly/slowly) into the plaque biofilm where it serves as a ___ for production of the extracellular polysaccharides and acids.
highly
rapidly
substrate
77
What are the main causal agent for caries?
streptococcus mutans
lactobacillus casei
lactobacillus fermentum
78
(Saccharolytic/Asaccharolytic) bacteria derive their energy from glycolysis.
saccharolytic
79
Acid produced from ___ bacteria causes caries.
saccharolytic
80
Biofilms on the tooth surfaces will form a dental ___.
plaque
81
Once a dental plaque becomes calcified it is called ___.
calculus (tartar)
82
Most healthy dentition and no periodontal disease have bacteria in the biofilms that are mostly gram __.
positive
83
Gram positive bacteria mainly ferment ____ to a final end product of _____.
```
sugars
lactic acid (saccharolytic)
```
84
Production of lactic acid results in (low/high) pH, which results in demineralization of tooth enamel and dentin resulting in caries.
low
85
Where do asaccharolytic bacteria derive their energy from?
amino acids
86
Free amino acid can be. ___ and ___.
deaminated
| reduced
87
What are the constituents of dental plaque?
ammonium acetate
ammonium propionate
ammonium butyrate
88
Dental calculus further promotes (a/saccharolytic) fermentation.
asaccharolytic
89
What causes oral malodor that is associated with periodontal disease?
cysteine and methionine ferment to produce hydrogen sulfide
90
What are the types of saliva?
serous
mucos
mixed
91
main product of the parotid glands
serous saliva
92
main product of the minor glands
mucos saliva
93
main product of sublingual and submandibular glands
mixed saliva
94
What makes up 99% of saliva?
water
95
Functions of saliva
```
lubricate and protect
buffering action and clearance
maintenance of tooth integrity
antibacterial activity
taste and digestion
saliva production up to 1L/day
```
96
What is secreted into the gingival sulcus?
gingival crevicular fluid (GCF)
97
functions of GCF
cleansing sulcus
improve adhesion of epithelium to tooth
antimicrobial properties
antibody defense of gingiva
98
What kind of environment does the GCF provide?
rich in proteins (asacharolytic)
| fermentation of AA to produce ammonia
99
Is the pH of GCF high or low and what is the purpose?
high
| prevent dental caries from developing
100
What is the downside to high pH of GCF?
lead to precipitation of calcium and phosphate on dental biofilm (plaque) and eventually formation of calculus
101
Asaccharolytic bacteria produces low or high pH?
high
102
Which bacteria would ampicillin mainly kill?
gram +
| bc of peptidoglycan
103
thin protein layer that forms on the surface of the enamel by binding of glycoproteins present in saliva.
pellicle
104
organisms (bacteria) that metabolize sugars to derive energy
saccharolytic bacteria
105
Soft biofilm that builds up on the teeth due to the attachment of bacteria to the tooth surface.
plaque
106
Harden form of plaque (often called tartar) that builds up on teeth due to the deposition of minerals into the plaque.
calculus
107
metabolic pathway used by cells to breakdown glucose to produce ATP energy and pyruvate, which can then be shuttled into the Krebs cycle.
glycolysis
108
metabolic pathway that cells use to breakdown fatty acids into Acetyl-CoA, which can enter into the Krebs cycle to produce energy.
beta-oxidation
109
also known as the Citric Acid cycle or the TCA cycle is a series of enzyme catalyzed chemical reactions that release stored energy by the oxidation of Acetyl-CoA.
krebs cycle
110
occurs in the inner mitochondrial membrane and involves a series of reactions that shuttle electrons from NADH and FADH2 to molecular oxygen. This results in the pumping of protons from the mitochondrial matrix into the mitochondrial intermembrane space and oxygen is reduced to form water. The H+ ions (protons) are pumped into the mitochondrial matrix through the ATP synthase enzyme, which uses the force of H+ ions flowing through it to phosphorylate ADP making ATP.
electron transport
111
The dental pellicle forms within (seconds/hours) after cleaning the teeth by the association of _____ in the salivary with the enamel surface.
seconds
| proteins
112
The pellicle serves as a further attachment matrix for oral bacteria, which produce a dental _____(plaque).
biofilm
113
Further mineralization of plaque leads to the formation of _______.
calculus
114
Bacteria metabolism within the dental biofilms produces ____ ___ and other end-products that contribute to the development of caries.
lactic acid
115
What has provided us with a wealth of resources and information so that we can now consider the practice of personalized dentistry based upon knowledge of an individual’s genetics and the biomes of the bacteria that colonize the oral cavity?
modern molecular biology
