Download Mitochondria

www.denniskunkel.com
Tour of the Cell
endoplasmic reticulum
ENDOPLASMIC RETICULUM (ER)
part 2
Rough ER
Today’s Topics
•  Functions of Major Cellular
Organelles
–  Information
•  Nucleus, Ribosomes
NUCLEUS
nucleus
Smooth ER
Plasma membrane
Centrosome
cytoskeleton
CYTOSKELETON
–  Synthesis&Transport
•  ER, Golgi, Vesicles
You should
know everything
in Fig 6.9
Microfilaments
–  Energy Conversion
•  Mitochondria, Chloroplasts
–  Recycling
•  Lysosome, Peroxisome
–  Structure and Movement
•  Cytoskeleton and Motor
Proteins
•  Cell Walls
Intermediate filaments
Microtubules
Ribosomes
ribosomes
cytosol
Golgi apparatus
Golgi
apparatus
Peroxisome
1
9/14/12
Figure 6.9
Mitochondrion
mitochondrion
www.denniskunkel.com
Lysosome
lysosome
In animal cells but not plant cells:
Lysosomes
Centrioles
Flagella (in some plant sperm)
2
Mitochondria
NUCLEUS
Food ! ATP
Mitochondrion
Intermembrane space
Outer
membrane
Free
ribosomes
in the
mitochondrial
matrix
Mitochondria
Inner
membrane
(and chloroplasts)
Cristae
Matrix
Mitochondrial
DNA
Figure 6.9
4
100 !m
3
Chloroplasts
ENDOPLASMIC RETICULUM (ER)
Rough ER
Chloroplast
Smooth ER
Sunlight ! ATP & Sugar
Ribosomes
Stroma
Chloroplast
DNA
Inner and outer
membranes
Granum
Peroxisome
1 !m
Thylakoid
5
Figure 6.9
Lysosome
Lysosome
(animals only)
6
1
ENDOPLASMIC RETICULUM (ER)
Rough ER
NUCLEUS
Smooth ER
Cytoskeleton
Cytoskeleton
CYTOSKELETON
Microtubule
Microfilaments
Intermediate filaments
Microtubules
Cytosol
0.25 !m
Figure 6.20
Figure 6.9
Microfilaments
7
Microtubules Microfilaments Intermediate
There are three
types of
fibers that
make up the
cytoskeleton
Tubulin
25 mM dia
Actin
7 mM dia
Filaments
8
Movement of Vesicles along Microtubules
various
8-15 mM dia
Vesicle
ATP
Cell shape
Organelle movt
Chromosome
separation
Flagellar mvt
Motors:
Dynein
Kinesin
Cell shape
Cell cleavage
Cytoplasmic
streaming
Muscle contract
Receptor for
motor protein
Nuclear
lamina
Tension
bearing
elements
Anchors
Motors:
Myosin
Motor protein
(ATP powered)
Microtubule
of cytoskeleton
(a) Motor proteins that attach to receptors on organelles can “walk”
the organelles along microtubules or, in some cases, microfilaments.
Microtubule
Vesicles
0.25 !m
What evidence do
we have that
they actually
move?
9
Figure 6.21 A, B
(b) Vesicles containing neurotransmitters migrate to the tips of nerve cell
axons via the mechanism in (a). In this SEM of a squid giant axon, two
vesicles can be seen moving along a microtubule. (A separate part of the
experiment provided the evidence that they were in fact moving.)
10
Table 6.1
Three kinds of Movement
•  Filament anchored: motor “walks” along
filament (transport vesicles)
•  Motor anchored: filament moves (muscles)
•  Both anchored: bending (cilia and flagella)
11
12
2
Fig. 6-24
Motor MAPs transport vesicles
Outer microtubule
doublet!
0.1 !m!
Dynein proteins!
Central
microtubules!
Microtubules!
Plasma
membrane!
Dynein
inbound
(b)!Cross section of
cilium!
Basal body!
0.5 !m!
(a)!Longitudinal
section of cilium!
outbound
kinesin
MTOC
Plasma
membrane!
0.1 !m!
Cilia and Flagella
Triplet!
Have 9+2 arrangement of microtubules
and motor proteins.
(c) Cross section of basal body!
13
14
Ribosomes (small brown dots)
Plants have 2 other support
mechanisms
Rough
endoplasmic
reticulum
•  Plant cell walls
Smooth
endoplasmic
reticulum
NUCLEUS
Golgi apparatus
–  cellulose fibers embedded in other
polysaccharides and protein
–  Located outside of the cell!
Central vacuole/Tonoplast
•  Cell Wall
•  Vacuole or
Tonoplast
Microfilaments
Intermediate
filaments
CYTOSKELETON
Microtubules
Mitochondrion
Peroxisome
Plasma membrane
Chloroplast
Cell wall
Wall of adjacent cell
Plasmodesmata
Figure 6.9
15
16
Extra Cellular Matrix
Central Vacuoles (Tonoplasts)
–  Only in plants
glycoproteins
Central vacuole
Cytosol
Acts like a “balloon in a
box” to hold plant cells
rigid
Tonoplast
Nucleus
Central
vacuole
Cell wall
Chloroplast
Figure 6.15
17
5 !m
18
3