Endocytosis Flashcards
Give some examples of what cells need to take in
- Nutrients
- Signals
- Antibodies
- Enzymes
- Membrane
- Viruses
- Bacteria
What are the three fates that endocytosed material can have?
- Degradation
- Storage
- Transcytosis
What is phagocytosis and how it is initiated?
Extension of membrane to engulf a solid particle to form an internal vesicle
Initiated by receptors
What is frustrated phagocytosis?
When 2 macrophages attempt to phagocytose the same material
What evidence is there to suggest cell membrane recycling occurs?
Macrophages phagocytosed latex beads
Able to estimate how much membrane had been internalised by counting the beads
But no changes in cell size
What is pinocytosis and how is it initiated?
A continuous process that allows cells to take up small molecules, like “drinking”. No initiation is required
If a particle is 0.3µm will it be phagocytosed or pinocytosed?
Pinocytosed
Particles >0.5µm are phagocytosed, otherwise, pinocytosed
What is formed when 3 molecules of clathrin link? What can these structures form?
Clathrin triskelia - These can link up to form pentagonal or hexagonal lattices
What is name given to the regions of the membrane that specialised in receptor-mediated endocytosis?
Clathrin coats
What happens to clathrin-coated pits at the endosome?
The low pH causes clathrin to dissociate
What are clathrin-coated pits?
Areas of membrane that are endocytosed to from cathrin coated vesicle
