Cell Organelles DSA Flashcards
The liver haptocyte has a high amount of this membrane
mitochondria inner membrane
the pancreatic exocrine cells has a high amount of this membrane
Rough ER membrane
What are the 3 topological categories
!) Nucleus and cytosol (communicate through nuclear pore
complex).
2) Organelles in secretory and endocytic pathways (ER, Golgi apparatus, endosomes, and lysosomes) (communicate through vesicles).
3) Mitochondria
what allows compartments to communicate with each other and cell exterior
fusion and budding
What compartments does the ER divide the cytoplasm into?
1) The luminal or cisternal compartment.
2) The cytoplasmic or cytosolic compartment
Rough ER imp functions
1) Proteins are modified &
Ribosomes assembled
2) Segregation of proteins for intracellular use and
3)Export from the cell (collagen, cell membrane proteins)
how are secretory proteins directed to the ER?
signal sequence
proteins that exit RER in vesicles travel to which portion of Golgi
cis portion
how does the smooth ER differ from rough ER?
- Lacks ribosomes
- Tubular cisternae
Functions of smooth ER
- Glycogen metabolism
- Lipid synthesis
- Phospholipid synthesis (other membranes)
- Detoxification
- Steroidogenesis
- Calcium regulation
- abundant in cells that make steroid or lipids
what are functions of the Golgi complex?
- Modification of carbohydrates attached to glycoproteins and proteoglycans
- Polysaccharide & oligosaccharide synthesis
- Synthesis of sphingomyelin and glycosphingolipids
- Sorting secretory products
- Packaging & storing secretory products into secretory granules or vesicles
what does the golgi complex mark lysomal enzymes with
mannose-6-phosphate (M6P)
the golgi dissembles during _____ and reassembles in _____
mitosis/meisosi and interphase
clathrin coated vesicles
transporting products from the Golgi apparatus to lysosomes or products from the exterior of the cell to lysosomes (like cholesterol)
COP (coat protein) I coated vesicles
transporting products between stacks of the Golgi apparatus
COP II coated vesicles
transporting products from the endoplasmic reticulum to the Golgi apparatus
what mediates clathrin binding to vesicular membrane
adaptin
in COP coated vesicles what leads to vesicle budding
coatomer
In COP coated vesicles what leads to disassembly of the vesicle coat
hydrolysis bound GTP changes ARF to GDP-bound leading to disassembly of the vesicle coat before the vesicles fuses with a target membrane
what causes the neck of a clatherin coated vesicle to be pinched off?
dynamin
what mediates clathrin binding to vesicle membrane?
adaptins
at what pH are lysosomes most active?
acidic pH
what is the lysosomal sorting pathway?
1) synthesis of lysomal enzyme
2) phosphorylation of lysosomal enzymes (mannose 6-P (M6P)
3) inter-golgi transporting vesicles
4) binding of lysosomal enzymes to M6P receptors
5) clathrin coated transporting vesicle
6) clathrin coat is lost. M6P receptor is recycled in Golgi and lysomal enzymes soared in primary lysosome
how to lysosomes maintain an acidic environment?
AtP-dependent H+ pump