Membrane Protein : Integral/Peripheral Integral Membrane Proteins (transmembrane) – Exposed to...
-
Upload
virgil-hines -
Category
Documents
-
view
220 -
download
0
Transcript of Membrane Protein : Integral/Peripheral Integral Membrane Proteins (transmembrane) – Exposed to...
![Page 1: Membrane Protein : Integral/Peripheral Integral Membrane Proteins (transmembrane) – Exposed to aqueous environment on both sides of the membrane – Used.](https://reader036.fdocuments.us/reader036/viewer/2022062308/56649da15503460f94a8dbf3/html5/thumbnails/1.jpg)
Membrane Protein : Integral/Peripheral
• Integral Membrane Proteins (transmembrane)– Exposed to aqueous
environment on both sides of the membrane
– Used to transport molecules across membrane
• Peripheral Membrane Proteins – Located on surface of a
membrane – Eg. Cytoskeleton
![Page 2: Membrane Protein : Integral/Peripheral Integral Membrane Proteins (transmembrane) – Exposed to aqueous environment on both sides of the membrane – Used.](https://reader036.fdocuments.us/reader036/viewer/2022062308/56649da15503460f94a8dbf3/html5/thumbnails/2.jpg)
Passive Membrane Transport • No chemical energy required• Diffusion– Net movement of a substance from a region of high
concentration to a region of low concentration until dynamic equilibrium between cells is met
![Page 3: Membrane Protein : Integral/Peripheral Integral Membrane Proteins (transmembrane) – Exposed to aqueous environment on both sides of the membrane – Used.](https://reader036.fdocuments.us/reader036/viewer/2022062308/56649da15503460f94a8dbf3/html5/thumbnails/3.jpg)
Simple Diffusion (Passive Transport)
• Diffusion of small/non-polar molecules across plasma membrane unassisted
![Page 4: Membrane Protein : Integral/Peripheral Integral Membrane Proteins (transmembrane) – Exposed to aqueous environment on both sides of the membrane – Used.](https://reader036.fdocuments.us/reader036/viewer/2022062308/56649da15503460f94a8dbf3/html5/thumbnails/4.jpg)
Facilitated Diffusion • Diffusion of large/polar molecules with the help of a
transport protein (integral membrane protein)• Stops when equilibrium is reached• Two types of Transport (Integtral) Proteins – Channel proteins– Carrier proteins
![Page 5: Membrane Protein : Integral/Peripheral Integral Membrane Proteins (transmembrane) – Exposed to aqueous environment on both sides of the membrane – Used.](https://reader036.fdocuments.us/reader036/viewer/2022062308/56649da15503460f94a8dbf3/html5/thumbnails/5.jpg)
Facilitated Diffusion • Channel Proteins– Form hydrophilic pathways in the membrane – Water and certain ions can pass
![Page 6: Membrane Protein : Integral/Peripheral Integral Membrane Proteins (transmembrane) – Exposed to aqueous environment on both sides of the membrane – Used.](https://reader036.fdocuments.us/reader036/viewer/2022062308/56649da15503460f94a8dbf3/html5/thumbnails/6.jpg)
Facilitated Diffusion • Carrier Proteins – Form pathways through the membrane– Bind to a specific solute (glucose, amino acid)– Carrier protein changes shape allowing solute to move
from one side of the membrane to the other
![Page 7: Membrane Protein : Integral/Peripheral Integral Membrane Proteins (transmembrane) – Exposed to aqueous environment on both sides of the membrane – Used.](https://reader036.fdocuments.us/reader036/viewer/2022062308/56649da15503460f94a8dbf3/html5/thumbnails/7.jpg)
Osmosis • Passive diffusion of water across a
membrane via aquaporins • Water always diffuses from an area of
low solute concentration (high water concentration) to an area of greater solute concentration (low water concentration)
• Three Solutions (Cell) • Hypotonic
– Solute concentration is high in cell (swells)• Hypertonic
– Solute concentration is low in cell (shrinks)• Isotonic
– Solute and water concentration is equal both in and outside cell
![Page 8: Membrane Protein : Integral/Peripheral Integral Membrane Proteins (transmembrane) – Exposed to aqueous environment on both sides of the membrane – Used.](https://reader036.fdocuments.us/reader036/viewer/2022062308/56649da15503460f94a8dbf3/html5/thumbnails/8.jpg)
Active Membrane Transport• Substance carried
across a membrane from an area of low concentration to an area of high concentration
• Use of pump• ATP used as energy
source
![Page 9: Membrane Protein : Integral/Peripheral Integral Membrane Proteins (transmembrane) – Exposed to aqueous environment on both sides of the membrane – Used.](https://reader036.fdocuments.us/reader036/viewer/2022062308/56649da15503460f94a8dbf3/html5/thumbnails/9.jpg)
Exocytosis and Endocytosis • Vesicles are used to
transport• ATP is required• Exocytosis– Transport of proteins and
waste material from cytosol to exterior of cell
• Endocytosis– Transport proteins and
large molecules into cytosol of the cell.