Use LEFT and RIGHT arrow keys to navigate between flashcards;
Use UP and DOWN arrow keys to flip the card;
H to show hint;
A reads text to speech;
8 Cards in this Set
- Front
- Back
|
Define Active Transport. |
The movement of molecules usually against its concentration gradient (low to high). |
|
|
Is active transport active or passive? |
Active - it needs energy. |
|
|
How does a carrier protein work in active transport? |
A molecule attaches, it changes shape and moves the molecule to the other side. |
|
|
Why is ATP important in AT? |
It provides the energy needed. |
|
|
How does ATP provide energy? |
Undergoes a hydrolysis reaction, splitting ATP to ADP and an inorganic phosphate. Splitting the phosphate group releases energy. |
|
|
How does a co-transporter work in AT? |
They are a type of carrier protein which binds two molecules at a time. The concentration gradient of one (going down) is used to take the other one with the negative concentration gradient across the membrane. |
|
|
Describe the co-transport and absorption of Glucose. |
Concentration of glucose is too low for glucose to diffuse of blood but it is needed in the small intestine. Sodium ion are actively transported out of epithelial cells into blood by Na-K pump. This creates a concentration gradient so there's a higher conc of sodium in the lumen than inside cell. Sodium ions diffuse from lumen to epithelial cells. By co-transporter. Which carries glucose into cell with it. Then glucose diffuses out of blood due to high conc into blood by facilitated diffusion. |
|
|
Name 3 factors which affect AT. |
Speed of carrier proteins. Number of carriers present. Availability of ATP and rate of respiration. |
