Transcript Slide 1

POWERPOINT® LECTURE SLIDE PRESENTATION
by LYNN CIALDELLA, MA, MBA, The University of Texas at Austin
UNIT 1
5
PART B
Membrane Dynamics
HUMAN PHYSIOLOGY
AN INTEGRATED APPROACH
DEE UNGLAUB SILVERTHORN
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FOURTH EDITION
Carrier-Mediated Transport
 Specificity
 Competition
 Saturation
 Transport maximum
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Vesicular Transport
 Phagocytosis
 Cell engulfs bacterium or other particle into
phagosome
 Endocytosis
 Membrane surface indents and forms vesicles
 Active process which can be nonselective
(pinocytosis) or highly selective
 Potocytosis uses caveolae
 Receptor-mediated uses clathrin-coated pits
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Receptor-Mediated Endocytosis
and Exocytosis
1 Ligand binds to membrane receptor.
9 Exocytosis
Extracellular fluid
2 Receptor-ligand migrates to
clathrin-coated pit.
8 Transport vesicle
and cell membrane
fuse (membrane
recycling).
Clathrincoated pit
3 Endocytosis
Receptor
Clathrin
7 Transport vesicle
with receptors moves
to the cell membrane.
5 Receptors
and ligands
separate.
To lysosome or
Golgi complex
6 Ligands go to lysosomes
or Golgi for processing.
Endosome
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44 Vesicle loses
clathrin coat.
Intracellular fluid
Figure 5-24
Receptor-Mediated Endocytosis
and Exocytosis
1 Ligand binds to membrane receptor.
Extracellular fluid
Receptor
Intracellular fluid
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Figure 5-24, step 1
Receptor-Mediated Endocytosis
and Exocytosis
1 Ligand binds to membrane receptor.
Extracellular fluid
2 Receptor-ligand migrates to
clathrin-coated pit.
Clathrincoated pit
Receptor
Clathrin
Intracellular fluid
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Figure 5-24, steps 1–2
Receptor-Mediated Endocytosis
and Exocytosis
1 Ligand binds to membrane receptor.
Extracellular fluid
2 Receptor-ligand migrates to
clathrin-coated pit.
Clathrincoated pit
3 Endocytosis
Receptor
Clathrin
Intracellular fluid
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Figure 5-24, steps 1–3
Receptor-Mediated Endocytosis
and Exocytosis
1 Ligand binds to membrane receptor.
Extracellular fluid
2 Receptor-ligand migrates to
clathrin-coated pit.
Clathrincoated pit
3 Endocytosis
Receptor
Clathrin
44 Vesicle loses
clathrin coat.
Intracellular fluid
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Figure 5-24, steps 1–4
Receptor-Mediated Endocytosis and
Exocytosis
1 Ligand binds to membrane receptor.
Extracellular fluid
2 Receptor-ligand migrates to
clathrin-coated pit.
Clathrincoated pit
3 Endocytosis
Receptor
Clathrin
5 Receptors
and ligands
separate.
Endosome
Copyright © 2007 Pearson Education, Inc., publishing as Benjamin Cummings
44 Vesicle loses
clathrin coat.
Intracellular fluid
Figure 5-24, steps 1–5
Receptor-Mediated Endocytosis and
Exocytosis
1 Ligand binds to membrane receptor.
Extracellular fluid
2 Receptor-ligand migrates to
clathrin-coated pit.
Clathrincoated pit
3 Endocytosis
Receptor
Clathrin
5 Receptors
and ligands
separate.
To lysosome or
Golgi complex
6 Ligands go to lysosomes
or Golgi for processing.
Endosome
Copyright © 2007 Pearson Education, Inc., publishing as Benjamin Cummings
44 Vesicle loses
clathrin coat.
Intracellular fluid
Figure 5-24, steps 1–6
Receptor-Mediated Endocytosis and
Exocytosis
1 Ligand binds to membrane receptor.
Extracellular fluid
2 Receptor-ligand migrates to
clathrin-coated pit.
Clathrincoated pit
3 Endocytosis
Receptor
Clathrin
7 Transport vesicle
with receptors moves
to the cell membrane.
5 Receptors
and ligands
separate.
To lysosome or
Golgi complex
6 Ligands go to lysosomes
or Golgi for processing.
Endosome
Copyright © 2007 Pearson Education, Inc., publishing as Benjamin Cummings
44 Vesicle loses
clathrin coat.
Intracellular fluid
Figure 5-24, steps 1–7
Receptor-Mediated Endocytosis and
Exocytosis
1 Ligand binds to membrane receptor.
Extracellular fluid
2 Receptor-ligand migrates to
clathrin-coated pit.
8 Transport vesicle
and cell membrane
fuse (membrane
recycling).
Clathrincoated pit
3 Endocytosis
Receptor
Clathrin
7 Transport vesicle
with receptors moves
to the cell membrane.
5 Receptors
and ligands
separate.
To lysosome or
Golgi complex
6 Ligands go to lysosomes
or Golgi for processing.
Endosome
Copyright © 2007 Pearson Education, Inc., publishing as Benjamin Cummings
44 Vesicle loses
clathrin coat.
Intracellular fluid
Figure 5-24, steps 1–8
Receptor-Mediated Endocytosis and
Exocytosis
1 Ligand binds to membrane receptor.
9 Exocytosis
Extracellular fluid
2 Receptor-ligand migrates to
clathrin-coated pit.
8 Transport vesicle
and cell membrane
fuse (membrane
recycling).
Clathrincoated pit
3 Endocytosis
Receptor
Clathrin
7 Transport vesicle
with receptors moves
to the cell membrane.
5 Receptors
and ligands
separate.
To lysosome or
Golgi complex
6 Ligands go to lysosomes
or Golgi for processing.
Endosome
44 Vesicle loses
clathrin coat.
Intracellular fluid
Exocytosis is the opposite of endocytosis
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Figure 5-24, steps 1–9
Transepithelial Transport
Polarized cells of transporting epithelia
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Figure 5-25
Transepithelial Transport of Glucose
[Glucose] low
Lumen of kidney
or intestine
Na+ [Na+] high
Glu
1
1 Na+ glucose symporter
brings glucose into cell
against its gradient using
energy stored in the Na+
concentration gradient.
2 GLUT transporter
transfers glucose to ECF
by facilitated diffusion.
Apical
membrane
[Glucose] high
Glu
Na+ [Na+] low
Epithelial
cell
Basolateral
membrane
Glu
Na+
3 Na+ -K+- ATPase pumps Na+
out of the cell, keeping ICF
Na+ concentration low.
K+
2
3
ATP
Extracellular
fluid
[Glucose] low
Glu
[Na+] high Na+
K+
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Figure 5-26
Transepithelial Transport of Glucose
Lumen of kidney
or intestine
[Glucose] low
Glu
Na+ [Na+] high
1
1
Na+ glucose symporter
brings glucose into cell
against its gradient using
energy stored in the Na+
concentration gradient.
Apical
membrane
[Glucose] high
Glu
Na+ [Na+] low
Epithelial
cell
Basolateral
membrane
Extracellular
fluid
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Figure 5-26, step 1
Transepithelial Transport of Glucose
[Glucose] low
Lumen of kidney
or intestine
Glu
Na+ [Na+] high
1
1 Na+ glucose symporter
brings glucose into cell
against its gradient using
energy stored in the Na+
concentration gradient.
2 GLUT transporter
transfers glucose to ECF
by facilitated diffusion.
Apical
membrane
[Glucose] high
Glu
Na+ [Na+] low
Epithelial
cell
Basolateral
membrane
Glu
2
Extracellular
fluid
[Glucose] low
Glu
Copyright © 2007 Pearson Education, Inc., publishing as Benjamin Cummings
Figure 5-26, steps 1–2
Transepithelial Transport of Glucose
[Glucose] low
Lumen of kidney
or intestine
Na+ [Na+] high
Glu
1
1 Na+ glucose symporter
brings glucose into cell
against its gradient using
energy stored in the Na+
concentration gradient.
2 GLUT transporter
transfers glucose to ECF
by facilitated diffusion.
Apical
membrane
[Glucose] high
Glu
Na+ [Na+] low
Epithelial
cell
Basolateral
membrane
Glu
Na+
3 Na+ -K+- ATPase pumps Na+
out of the cell, keeping ICF
Na+ concentration low.
K+
2
3
ATP
Extracellular
fluid
[Glucose] low
Glu
[Na+] high Na+
K+
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Figure 5-26, steps 1–3
Transcytosis across the Capillary Endothelium
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Figure 5-27
Transcytosis across the Capillary Endothelium
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Figure 5-27 (1 of 3)
Transcytosis across the Capillary Endothelium
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Figure 5-27 (2 of 3)
Transcytosis across the Capillary Endothelium
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Figure 5-27 (3 of 3)
Transcytosis across the Capillary Endothelium
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Figure 5-27