Active and Co-transport Flashcards
What is Active transport?
Movement of substance from a region of low concentration to a region of high concentration. Requires energy in the form of ATP
What is Co-transport?
The transport of one substance coupled with the transport of another substance across a plasma membrane in the same direction through the same protein carrier
What happens during Co-transportation?
Two molecules bind, one moves down its concentration gradient and this is used to move the other molecule across the membrane against its concentration gradient e.g. Glucose and Sodium
What creates a concentration gradient using sodium and glucose?
Na+ ions ace actively transported out of the epithelial cells into the blood by the sodium potassium. There are more Sodium ions in the lumen than inside the epithelial cell
What does the concentration gradient cause?
Na+ ions diffuse from the lumen of the ileum into the epithelial cell down their concentration gradient and Glucose enters the cell with the Sodium
What happens when the glucose concentration is higher in the epithelial cell than in the blood?
Glucose diffuses into the blood down its concentration gradient through a protein channel by Facilitated Diffusion
What are the factors affecting Active transport?
Speed of Carrier Proteins, Number of Carrier Proteins and Rate of Respiration
What is the relationship of Speed of Carrier Proteins?
The faster they work, the faster the rate of Active transport
What is the relationship of Number of Carrier Proteins?
The greater the number of carrier proteins in the plasma membrane, the faster the rate of active transport
What is the relationship of Rate of Respiration?
The greater the rate of respiration, the more ATP there will be available for active transport to take place
What is Endocytosis?
Move particles into a cell by enclosing them in a vesicle made out of a plasma membrane
What is Exocytosis?
Cells transport signalling chemicals or waste products from the inside of the cell to the outside of the cell in vesicles which fuse with the plasma membrane
What is an Receptor-mediated endocytosis?
Uses receptor proteins on the cell surface to capture a specific target molecule. When the receptor binds to the target molecule, endocytosis is triggered.
