Week 5: ER And Golgi Flashcards
What are the two main processes of intracellular vesicular traffic?
Exocytosis and Endocytosis
Exocytosis is the transport from ER/Golgi/endosomes to the cell membrane, while endocytosis is the transport from the cell membrane to lysosomes or endosomes.
Define Exocytosis in the context of vesicular traffic.
Transport from ER/Golgi/endosomes to cell membrane
This process is essential for delivering newly synthesized macromolecules to the exterior.
What is the purpose of Endocytosis?
Ingestion of other cells and molecules for degradation or recycling
This occurs in lysosomes, where macromolecules are digested.
What are the three pathways of Endocytosis?
- Recycling
- Transcytosis
- Degradation
Recycling returns proteins to another compartment, transcytosis transports materials across the cell, and degradation breaks down unwanted materials.
Fill in the blank: Vesicles bud off from one membrane and _______ with another.
fuse
What type of vesicles are formed during intracellular transport?
Coated vesicles
These vesicles have specific protein coats that determine their transport pathway.
Name the three types of coated vesicles.
- Clathrin-coated
- COPI-coated
- COPII-coated
Each type has specific functions in intracellular transport.
What is the role of SNARE proteins in vesicular transport?
Control recognition of specific target membrane and subsequent fusion
vSNARE and tSNARE facilitate docking and fusion of vesicles with target membranes.
True or False: Autophagy refers to the process of ingesting other cells.
False
Autophagy, or ‘self-eat’, is the process of degrading cellular components.
What is the main site of intracellular digestion of macromolecules?
Lysosomes
What pH environment is required for lysosomal enzymes to function?
pH 5.0
Lysosomes contain about 40 types of hydrolytic enzymes that require this acidic environment.
What are the two models explaining the organization of the Golgi apparatus?
- Vesicle Transport
- Cisternal Maturation
These models explain how proteins move through the Golgi apparatus.
Fill in the blank: The _______ pathway is the default pathway for transport from the Golgi.
Constitutive
What is the function of the Golgi apparatus?
Sorting and dispatching station for products of the ER
It also plays a role in carbohydrate production and modification of molecules.
What are the two main pathways for transport from the Golgi?
- Constitutive secretory pathway
- Regulated secretory pathway
The regulated pathway requires a signal for secretion.
