Flashcards in Cells - Transport across cell membranes - 18.104.22.168 - Active Transport Deck (15)
The movement of molecules or ions AGAINST a concentration gradient using ATP and carrier proteins is describing...
Difference between active transport and facilitated diffusion
1. active transport uses ATP
2. Active transport uses only carriers (FD uses channels and carriers)
3. Active transport moves molecules against their concentration gradient
Differences between active transport and osmosis
1. Active transport moves solutes or ions osmosis water moves
2. Active transport uses a carrier to transport a molecule across the plasma membrane, osmosis water moves through the membrane directly
In active transport what does the molecule that is moving bind to on the carrier molecule?
A receptor/binding site
After the molecule has bound to the receptor on the carrier (in active transport), what happens next?
ATP binds to the carrier on the opposite side, it splits into ADP and Phosphate (P) (releasing energy) causing the carrier to change shape, allowing the entry of the molecule.
Why do some cells like root hair cells possess so many mitochondria?
Because they transport mineral ions against a concentration gradient. This requires energy
What is unique about the carrier proteins used in active transport?
they have a specific tertiary structure
Where is active transport used in humans?
Gut/Small intestine - absorption of glucose
How is low levels of glucose absorbed in the small intestine?
Using Na co transporter - ATP used indirectly
Which form of cell transport requires energy?
Which type of protein are involved in active transport?
rate of active transport is affected by..
1. speed of carrier molecules
2. number of carrier molecules
3. rate of respiration - ATP availability
How does more carrier molecules affect active transport?
increases the rate
How does an inhibitor of respiration affect active transport?
Less or NO ATP produced to rate of active transport reduced