Cell transport mechanisms
This presentation is the property of its rightful owner.
Sponsored Links
1 / 23

Cell Transport Mechanisms PowerPoint PPT Presentation


  • 76 Views
  • Uploaded on
  • Presentation posted in: General

Cell Transport Mechanisms. Moving molecules across the Cell Membrane. Two methods: Passive Transport Active Transport. Passive Transport. Allows molecules to ____________ according to natural laws of physics. Everything tends towards___________.

Download Presentation

Cell Transport Mechanisms

An Image/Link below is provided (as is) to download presentation

Download Policy: Content on the Website is provided to you AS IS for your information and personal use and may not be sold / licensed / shared on other websites without getting consent from its author.While downloading, if for some reason you are not able to download a presentation, the publisher may have deleted the file from their server.


- - - - - - - - - - - - - - - - - - - - - - - - - - E N D - - - - - - - - - - - - - - - - - - - - - - - - - -

Presentation Transcript


Cell transport mechanisms

Cell Transport Mechanisms


Moving molecules across the cell membrane

Moving molecules across the Cell Membrane

Two methods:

Passive Transport

Active Transport


Passive transport

Passive Transport

Allows molecules to ____________ according to natural laws of physics

Everything tends towards___________

Three types of passive transport mechanisms:

-

-

-


Passive transport diffusion

Passive Transport – Diffusion

Movement of molecules is __________

When they bump into each other, they _________________

When they are __________ concentrated, they bump into each other _____________________

This forces molecules to move from areas of ________ concentration to areas of ________ concentration

High Concentration

_________a ___________________

“_______________”

Low Concentration


Passive transport diffusion1

Passive Transport – Diffusion

=

___________

When molecules have reached equal concentrations in both locations, diffusion ends.

Molecules _________ moving, but they move in ______________ equally. _________________.


Diffusion across a membrane

Diffusion across a Membrane

Examples:

small molecules (CO2,O2)

small lipids

alcohol

Prediction?

Prediction?


Passive transport osmosis

Passive Transport – Osmosis

Moves ________ molecules across cell membrane (into or out of cells)

Molecules still move down the concentration gradient

Purple dots are solutes, not water molecules


Passive transport osmosis1

Passive Transport – Osmosis

Predict Results


Passive transport osmosis2

Passive Transport – Osmosis

Osmotic Pressure –

Pressure created by the presence of water in the cell

…cell _______or ________

Example: Blood cell in low/high salt solutions


Cell transport mechanisms

Passive Transport – Osmosis

Hypertonic Solution:

Conc. of solutes outside cell is ________

Animal Cell

5% salt

2% salt

Plant Cell

Water _______ cell


Cell transport mechanisms

Passive Transport – Osmosis

Isotonic Solution:

Conc. of solutes outside cell is _________inside cell

Animal Cell

5% salt

5% salt

Plant Cell

Water ____________cell _____________

_____ _______ ______________


Passive transport osmosis3

Passive Transport – Osmosis

Hypotonic Solution:

Conc. of solutes outside cell is _________

Animal Cell

2% salt

5% salt

Plant Cell

Water ________ cell


Passive transport facilitated diffusion

Passive Transport – Facilitated Diffusion

Molecules still move down the concentration gradient, but cannot pass phospholipids on their own.

Rely on __________ imbedded in membrane to “________” them across

Proteins are specific to _____________________________________

_____________

______________

Examples:

water

salt

ions

glucose


Active transport

Active Transport

Moves molecules __________ the concentration gradient from areas of _________ concentration to areas of __________ concentration.

Restores ________

Takes _______ to “go _______”

_____________move molecules into or out of cell ______ gradient.

Outside Cell

Inside Cell


Active transport1

Active Transport

Endocytosis

Moving molecules ________cells

___________: “cellular _________”

___________: “cellular _________”

Exocytosis

Moving molecules _____cells


Endo cytosis

Endocytosis

Molecules move into a “pocket” of the cell membrane


Endo cytosis1

Endocytosis

“Pocket” pinches off the membrane into cytoplasm


Endo cytosis2

Endocytosis

________ has now formed and can move around inside cell


Exo cytosis

Exocytosis

_______ pinches off ________________


Exo cytosis1

Exocytosis

Free vesicle migrates towards cell membrane


Exo cytosis2

Exocytosis

Vesicle contacts cell membrane and begins to fuse with it


Exo cytosis3

Exocytosis

As vesicle becomes part of plasma membrane, contents spill out of cell


Endocytosis and exocytosis

Endocytosis and Exocytosis

These two processes occur at roughly the same rate

=

__________________________________________


  • Login