44 4.32 Active Uptake/Transport
There are two forms of active uptake/transport:
1. Active Carrier Transport
2. Endocytosis
1. Active Carrier Transport
Active carrier transport is similar to facilitated diffusion in that it utilizes a protein (carrier). However, energy is also used to move compounds against their concentration gradient. The following figure and video do a nice job of illustrating active carrier transport.
| Web Link |
2. Endocytosis
Endocytosis is the engulfing of particles, or fluids, to be taken up into the cell. If a particle is endocytosed, this process is referred to as phagocytosis. If a fluid is endocytosed, this process is referred to as pinocytosis as shown below.
The following video does a really nice job of showing how endocytosis occurs.
| Web Link |
References & Links
1. https://en.wikipedia.org/wiki/File:Scheme_sodium-potassium_pump-en.svg
2. http://commons.wikimedia.org/wiki/File:Endocytosis_types.svg
Videos
Active Transport – http://www.youtube.com/watch?v=STzOiRqzzL4
Endocytosis – http://www.youtube.com/watch?v=4gLtk8Yc1Zc