Endocytosis and exocytosis Flashcards
why is endocytosis and exocytosis important ?
cells use endocytosis and exocytosis to transfer large molecules across the cell membrane.
what is bulk transport?
endocytosis and exocytosis transferring large quantities of material.
what is endocytosis?
in endocytosis particles or molecules are transported into the cell, this can include large molecule such as proteins as well as cells such as bacteria
what happens in the first stage of endocytosis?
In the first stage, the cell membrane folds inwards to form a cavity around the particle.
what happens in the second stage of endocytosis?
the membrane completely encircles the particle to form a vesicle and it moves into the cell.
what is exocytosis?
exocytosis moves material out of the cell, this includes secreted proteins such as hormones and certain enzymes.
what happens at the start of exocytosis?
At the start of exocytosis these proteins are found in the golgi apparatus. the proteins are modified before secreted
what happens in the second stage of exocytosis?
next vesicles contain the protein that bud off the golgi apparatus and make their way out of the cell membrane
what happens in the third stage of exocytosis?
The vesicle then fuses with the cell membrane and the protein is secreted.
what does endocytosis and exocytosis need in order for it to happen?
they require energy from ATP.
