Active transport Flashcards
Active transport
It is the transport of molecules or ions across the cell membrane through carrier proteins by using energy from respiration (ATP). It transports substances against the concentration gradient
How active transport work (not done)
The carrier protein is very specific picking up only one type of ion or molecule or they they may work with several similar substances that have to compete with each other for a place on the carrier.
Active transport will move substances only in the direction required by the cell.
This method can move substances faster than diffusion
Cytosis
Large molecules such as proteins & polysaccharides & even whole cells are moved in & out of cells by using vesicles.
ATP is used in the movement of verticals with the cells
Cytosis
Endocytosis
Exocytosis
Cytosis & cell membrane
The membrane is principally held together by weak hydrophobic associations between fatty acids tails of phospholipids
This weak association allows for membrane fluidity & flexibility as the phospholipids can move around to some extent.
This allows for the spontaneous breaking & reforming of the bilayer allowing larger materials to enter or leave the cell without having to cross the membrane
Cytosis: endocytosis
It is the transport of materials into a cell by forming vesicles. Materials are enclosed by a fold of the cell membrane which then depends & pinches of from the cell membrane to form a closed vesicles
Endocytosis
Phagocytosis
Pinocytosis
Phagocytosis
If the materials are large solids such as white blood cells ingesting bacterial cell the process is known as phagocytosis (cell eating)
Pinocytosis
If the material being taken into vesicles are liquid or solutions such as protein molecules the process is known as pinocytosis (cell drinking)
Cytosis: exocytosis
Exocytosis is the transposed of materials out of a cell by using vesicles. It is the exact reverse of endocytosis
