Zusammenfassung der Ressource
Active
Transport
- Unlike Diffusion
Anlagen:
- Diffusion = High
concentration to low
concentration
- Along a concentration gradient
- Low concentration to
high concentration
- Against a concentration gradient
- Used to transport dissolved
molecules from a low
concentration to a high
concentration
- Against the
concentration
gradient
- Requires energy
from respiration
- Protein
carriers
- Responsible for carrying
specific molecules through
a cell membrane into a cell
- Binding site, allows molecules to bind
to outside of membrane
- Energy from
respiration changes
the shape of the
protein
- Releases the
substance
onto the other
side of the membrane
- Examples from nature:
- Root hair cells
- Need to absorb ions (like
nitrates) from soil for
nutrients
- Small intestine villi cells
- Alongside diffusion, maximises
absorption of glucose and other
substances