| What are the 2 secretory pathways | Constitutive and Regulated |
| Difference between constituitive and regulated secretory pathways | The main difference is that the constitutive has an unregulated membrane fusion while a regulated secretory pathway has a regulated membrane fusion (needs a signal) |
| Collagen synthesis is done by what cell in connective tissue | Fibroblasts |
| Features of collagen fibres? | Triple Helix, Hydrogen bonds between chains stabilise structure, Glycine every 3rd postion and each basic unit is tropocollagen and is rod shaped ( collagen fibres ) |
| What features does the triple helix give collagen | Non-compressible, high tensile strength and non-extensibile |
| Synthesis and modification of collagen in ER, consits of what processes | Prepro alpha chains into pro alpha chains then hydroxylation then glycolysation then addition of disulfide bonds and finally folding but not at 150 N-terminal amino acids and 250 C-terminal amino acids |
| What happens to procollagen in the Golgi Body | Glucose added to galactose and then transported to plasma membrane through vesicles |
| How is tropocollagen formed? | Removal of N and C terminals by procollagen peptidase |
| EDS otherwise known as Ehlers-Danlos syndrome is caused by what | Mutation in collagen type I,III,V or lsyl oxidase deficiency |
| Which 3 enzymes are required for insulin proteolytic processing? | C2 endoprotease, C3 endoprotease and carboxypeptidase |
| How does insulin be released | Blood glucose level increases - > Glucose enters Beta-islets cells so intracellular glucose increases -> This causes Ca2+ to be released from ER -> Ca2+ increase leads to insulin containing vesicles to be released |
| Why is proteolytic processing so common in the secretory pathway? | Products can be too small to enter co-translational mechanisms
Products can be destructive if released inside the cell
Many bioactive products can be made from the same polypeptide |
