Embed Size (px)
Citation preview
Cells: Honors Biology ~ Edgar
Hemocytometer
Counting Guidelines
• Cells Should not be overlapping.
• Cells should be uniformly distributed
• You need to count 100 cells to be statistically significant.
• Where to Count – no bias.
Which Cells to Count
Peptidoglycancell walls
Figure 6.8a
ENDOPLASMIC RETICULUM (ER)
RoughER
SmoothER
Nuclearenvelope
Nucleolus
Chromatin
Plasmamembrane
Ribosomes
Golgi apparatus
LysosomeMitochondrion
Peroxisome
Microvilli
MicrotubulesIntermediate filaments
Microfilaments
Centrosome
CYTOSKELETON:
Flagellum NUCLEUS
Figure 6.8c
NUCLEUS
Nuclearenvelope
Nucleolus
Chromatin
Golgiapparatus
Mitochondrion
Peroxisome
Plasma membrane
Cell wall
Wall of adjacent cell
Plasmodesmata
Chloroplast
Microtubules
Intermediatefilaments
Microfilaments
CYTOSKELETON
Central vacuole
Ribosomes
Smoothendoplasmicreticulum
Roughendoplasmic
reticulum
Cell Biology and Diabetes
Red arrows indicate Beta Cells
Endomembrane System
Proinsulin - Orange
Figure 11.5a
Local signaling
Target cell
Secretingcell
Secretoryvesicle
Local regulatordiffuses throughextracellular fluid.
(a) Paracrine signaling (b) Synaptic signaling
Electrical signalalong nerve celltriggers release ofneurotransmitter.
Neurotransmitter diffuses across synapse.
Target cellis stimulated.
Figure 11.5b
Long-distance signaling
Endocrine cell Bloodvessel
Hormone travelsin bloodstream.
Target cellspecificallybinds hormone.
(c) Endocrine (hormonal) signaling
Figure 11.6-1
Plasma membrane
EXTRACELLULARFLUID
CYTOPLASM
Reception
Receptor
Signalingmolecule
1
Figure 11.6-2
Plasma membrane
EXTRACELLULARFLUID
CYTOPLASM
Reception Transduction
Receptor
Signalingmolecule
Relay molecules in a signal transductionpathway
21
Figure 11.6-3
Plasma membrane
EXTRACELLULARFLUID
CYTOPLASM
Reception Transduction Response
Receptor
Signalingmolecule
Activationof cellularresponse
Relay molecules in a signal transductionpathway
321
Igf-1
Insulin-like growth factor 1
Types of Cell Receptors
GCPR on Beta Cells
Figure 11.7c
Signalingmolecule (ligand)
21
3 4
Ligand-binding site
helix in themembrane
Tyrosines
CYTOPLASM Receptor tyrosinekinase proteins(inactive monomers)
Signalingmolecule
Dimer
Tyr
Tyr
Tyr
Tyr
Tyr
Tyr
Tyr
Tyr
Tyr
Tyr
Tyr
Tyr
Tyr
Tyr
Tyr
Tyr
Tyr
Tyr
Tyr
Tyr
Tyr
Tyr
Tyr
Tyr
Tyr
Tyr
Tyr
Tyr
Tyr
Tyr
Tyr
Tyr
Tyr
Tyr
Tyr
Tyr
P
P
P
P
P
P
P
P
P
P
P
P
Activated tyrosinekinase regions(unphosphorylateddimer)
Fully activatedreceptor tyrosinekinase(phosphorylateddimer)
Activated relayproteins
Cellularresponse 1
Cellularresponse 2
Inactiverelay proteins
6 ATP 6 ADP
Insulin Receptortyrosine kinase receptor
Signal Transduction Pathway
Figure 11.7d
Signalingmolecule (ligand)
21 3
Gate closed Ions
Ligand-gatedion channel receptor
Plasmamembrane
Gate open
Cellularresponse
Gate closed
Figure 11.10
Receptor
Signaling molecule
Activated relaymolecule
Phosphorylation cascade
Inactiveprotein kinase
1 Activeprotein kinase
1
Activeprotein kinase
2
Activeprotein kinase
3
Inactiveprotein kinase
2
Inactiveprotein kinase
3
Inactiveprotein
Activeprotein
Cellularresponse
ATPADP
ATPADP
ATPADP
PP
PP
PP
P
P
P
P i
P i
P i
Second Messengers
Figure 11.12
G protein
First messenger(signaling moleculesuch as epinephrine)
G protein-coupledreceptor
Adenylylcyclase
Second messenger
Cellular responses
Proteinkinase A
GTP
ATP
cAMP
Figure 11.16
Reception
Transduction
Response
Binding of epinephrine to G protein-coupled receptor (1 molecule)
Inactive G protein
Active G protein (102 molecules)
Inactive adenylyl cyclaseActive adenylyl cyclase (102)
ATPCyclic AMP (104)
Inactive protein kinase AActive protein kinase A (104)
Inactive phosphorylase kinase
Active phosphorylase kinase (105)
Inactive glycogen phosphorylase
Active glycogen phosphorylase (106)
Glycogen
Glucose 1-phosphate (108 molecules)
Figure 11.13
Mitochondrion
EXTRACELLULARFLUID
Plasmamembrane
Ca2
pump
Nucleus
CYTOSOL
Ca2
pump
Ca2
pump
Endoplasmicreticulum(ER)
ATP
ATP
Low [Ca2 ]High [Ca2 ]Key
Figure 11.14-1
G protein
EXTRA-CELLULARFLUID
Signaling molecule(first messenger)
G protein-coupledreceptor
Phospholipase C
DAG
PIP2
IP3
(second messenger)
IP3-gatedcalcium channel
Endoplasmicreticulum (ER)
CYTOSOL
Ca2
GTP
Figure 11.14-2
G protein
EXTRA-CELLULARFLUID
Signaling molecule(first messenger)
G protein-coupledreceptor
Phospholipase C
DAG
PIP2
IP3
(second messenger)
IP3-gatedcalcium channel
Endoplasmicreticulum (ER)
CYTOSOL
Ca2
(secondmessenger)
Ca2
GTP
Figure 11.14-3
G protein
EXTRA-CELLULARFLUID
Signaling molecule(first messenger)
G protein-coupledreceptor
Phospholipase C
DAG
PIP2
IP3
(second messenger)
IP3-gatedcalcium channel
Endoplasmicreticulum (ER)
CYTOSOL
Variousproteinsactivated
Cellularresponses
Ca2
(secondmessenger)
Ca2
GTP
Diabetes
Looking good. The pancreas of a mouse after it was transplanted with human beta cells (left) looks similar to that of an animal that produces insulin normally (right).
CREDIT: Narushima et al., Nature Biotechnology
Brimming with b's. Newfound cells in the pancreas give rise to neurons (red) and insulin-producing b cells (green).CREDIT: SEABERG ET AL., NATURE BIOTECHNOLOGY
The full picture. Human ES cells can eventually give rise to cells that resemble pancreatic beta cells (labeled β).
Cell Membranes and Transport
Honors Biology ~ Edgar
Glucose, Starch, IKI, Water
Osmosis
Osmosis
Concept Check
• If a Paramecium were to swim from a hypotonic environment to an isotonic one, would the activity of its contractile vacuole increase or decrease? Why?
Concept Check• This diagram represents osmosis
of water across a semipermeable membrane. The U-tube on the right shows the results of the osmosis. What could you do to level the solutions in the two sides of the right hand U-tube?a) Add more water to the left hand side.
b) Add more water to the right hand side.
c) Add more solute to the left hand side.
d) Add more solute to the right hand side.
Answer
•This diagram represents osmosis of water across a semipermeable membrane. The U-tube on the right shows the results of the osmosis. What could you do to level the solutions in the two sides of the right hand U-tube?
c) Add more solute to the left hand side.
Sodium Potassium
Pump
Jmol
Harvard BioVisions
Vegetables in Sucrose Solutions
-30.00
-20.00
-10.00
0.00
10.00
20.00
30.00
0 0.2 0.4 0.6 0.8 1 1.2
Sucrose Concentration (Molarity)
Per
cen
t C
han
ge
in M
ass
(%)
Beet
Potato
Carrot
Figure 11.2
Exchange of mating factors
Receptor factor
a factorYeast cell,
mating type aYeast cell,
mating type
Mating
New a/ cell
1
2
3
a
a
a/
Figure 11.17
Wild type (with shmoos) Fus3 formin
Matingfactoractivatesreceptor.
Matingfactor G protein-coupled
receptor
Shmoo projectionforming
Formin
G protein binds GTPand becomes activated.
2
1
3
4
5
P
P
P
PForminFormin
Fus3
Fus3Fus3
GDPGTP
Phosphory- lation cascade
Microfilament
Actinsubunit
Phosphorylation cascadeactivates Fus3, which movesto plasma membrane.
Fus3 phos-phorylatesformin,activating it.
Formin initiates growth ofmicrofilaments that formthe shmoo projections.
RESULTS
CONCLUSION
