Active Transport Flashcards
How do polar molecules and ions move across the membrane?
Via protein channels and carrier proteins (facilitated diffusion).
What happens in active transport?
Carrier proteins in the membrane transport a chemical against the concentration gradient.
What does active transport require?
Metabolic energy provided by ATP.
Which way do molecules move in active transport?
Both into and out of the cell.
What is the first thing to happen in active transport across a membrane?
The molecule or ion on the lower concentration side of the membrane attaches to a receptor site on the carrier protein.
What then binds to the carrier protein after the ion attaches to the receptor site?
ATP molecule.
What happens to the ATP molecule after it binds to the carrier protein?
It undergoes hydrolysis to produce a phosphate molecule and ADP.
What does the phosphate molecule produces from ATP do?
Attaches to the carrier protein causing it to change shape.
What does the carrier proteins change in shape cause?
The molecule or ion to be transported to the other side of the membrane where it is released.
What happens after the ion or molecule is released form the carrier protein?
The phosphate leaves the carrier protein which causes it to return back to its original shape.
What will happen to the de attached phosphate molecule and ADP?
They will later reform ATP during respiration.
Why do we tend to find lots of mitochondria in cells that carry out active transport?
Since ATP required in active transport is formed during respiration in the mitochondria.
What are specific in active transport?
Carrier proteins.
What does specific mean?
Only one type of molecule can be transported.
What’s a difference in active transport and facilitated diffusion?
Different carrier proteins are used.
