100% satisfaction guarantee Immediately available after payment Both online and in PDF No strings attached
logo-home
MCB 2050 Exam Questions and Answers 100% Solved $10.99   Add to cart

Exam (elaborations)

MCB 2050 Exam Questions and Answers 100% Solved

 4 views  0 purchase
  • Course
  • MCB 2050
  • Institution
  • MCB 2050

MCB 2050 Exam Questions and Answers 100% Solved rough endoplasmic reticulum - mostly cisternae w/bound ribosomes, involved in protein and membrane phospholipid synthesis smooth endoplasmic reticulum - mostly curved tubules lacking ribosomes, involved in Ca2+ storage and hormone synthesis oute...

[Show more]

Preview 4 out of 32  pages

  • October 12, 2024
  • 32
  • 2024/2025
  • Exam (elaborations)
  • Questions & answers
  • MCB 2050
  • MCB 2050
avatar-seller
JOSHCLAY
©JOSHCLAY 2024/2025. YEAR PUBLISHED 2024.

MCB 2050 Exam Questions and Answers

100% Solved


rough endoplasmic reticulum - ✔✔mostly cisternae w/bound ribosomes,

involved in protein and membrane phospholipid synthesis

smooth endoplasmic reticulum - ✔✔mostly curved tubules lacking

ribosomes, involved in Ca2+ storage and hormone synthesis

outer nuclear membrane - ✔✔continuous w/RER, contains nups and

attached ribosomes

2 concentric phospholipid bilayers arranged in parallel and separated by

nuclear envelope lumen, joined at NPCs

MAM and PAM - ✔✔mitochondria and plasma membrane-associated

membranes

regions of ER that make direct contact w/mitochondria or pm

involved in membrane lipid exchnage

ERES - ✔✔ER exit sites

ER subdomain located next to cisface of Golgi

, ©JOSHCLAY 2024/2025. YEAR PUBLISHED 2024.

responsible for packaging of vesicles w/correct proteins and lipids destined

for Golgi

reticuloplasmins - ✔✔chaperones that operate at the ER

bind to nascent soluble or membrane proteins and mediate their proper

folding and oligomeric assembly (prevent protein aggregation)

ex. BiP, calnexn, calreticulin

sec61 translocon - ✔✔hourglass-shaped pore containing a pore ring of 6

hydrophobic AAs located at the narrowest diamater of the pore

- AA side chains act as a gate

- alpha-helix prevents ion movement/small molecules movement b/w ER

lumen and cytoplasm - maintains ER organelle compartmentalization

N-linked glycosylation - ✔✔addition of sugar monomers to the terminal

amino group of an asparagine

2 stages: core glycosylation and core modification

core glycosylation - ✔✔step 1 of N-linked glycosylation

- a sugar is added to dolichol phsophate, a lipid carrier, then more sugar

are added one a time

- core is flipped across the ER membrane into the ER lumen during its

synthesis

, ©JOSHCLAY 2024/2025. YEAR PUBLISHED 2024.

- glycosyltransferase links the core oligosaccharide to the NXS/T

sequence on a soluble or integral membrane protein that's still being

synthesized in the Sec61 co-translational translocation pathway

- dolichol phosphate is recycled for another round of core oligosaccharide

synthesis

core modification - ✔✔step 2 of N-linked glycosylation

- two of the terminal glucose units are trimmed by glucosidase I and II

- nascent glycoprotein is folded by reticuloplasmins and undergoes protein

control during this process

ER protein quality control - ✔✔- nascent glycoprotein (w/1 remaining

terminal glucose) binds to calnexin, which mediates final folding steps

glucosidase II then trims the last glucose unit, releasing the protein from

calnexin

- if properly folded, protein goes and lives it's life

- if misfolded is recognized by the UGGT monitoring enzyme, which adds a

glucose residue back, at which point the protein binds to calnexin again

and the process repeats until the protein is properly folded or is destroyed

via the ERAD pathway

, ©JOSHCLAY 2024/2025. YEAR PUBLISHED 2024.

ERAD pathway - ✔✔- oligosaccharide chain is removed and protein is

poly-ubiquinated

- UB-protein binds to cap of proteasome, the UB is removed and recycled

and the protein is threaded into the proteasome and degraded

- AAs are reused for new protein synthesis

mono-UB - ✔✔serves as signal for membrane protein import into late

endosomal intralumenal vesicles

poly-UB - ✔✔serves as signal for ER protein degradation and for most

other cellular proteins destined for normal turnover

calnexin - ✔✔membrane-bound reticuloplasmin

UGGT monitoring enzyme - ✔✔glycosyltransferase that recognizes

hydrophobic residues that are usually masked by the attached

oligosaccharide core in a correctly folded protein

UPR pathway - ✔✔unfolded protein response

occurs under ER stress (misfolded proteins accumulate in ER to high levels

due to overload of ERAD pathway)

two types: PERK and ATF-6

The benefits of buying summaries with Stuvia:

Guaranteed quality through customer reviews

Guaranteed quality through customer reviews

Stuvia customers have reviewed more than 700,000 summaries. This how you know that you are buying the best documents.

Quick and easy check-out

Quick and easy check-out

You can quickly pay through credit card or Stuvia-credit for the summaries. There is no membership needed.

Focus on what matters

Focus on what matters

Your fellow students write the study notes themselves, which is why the documents are always reliable and up-to-date. This ensures you quickly get to the core!

Frequently asked questions

What do I get when I buy this document?

You get a PDF, available immediately after your purchase. The purchased document is accessible anytime, anywhere and indefinitely through your profile.

Satisfaction guarantee: how does it work?

Our satisfaction guarantee ensures that you always find a study document that suits you well. You fill out a form, and our customer service team takes care of the rest.

Who am I buying these notes from?

Stuvia is a marketplace, so you are not buying this document from us, but from seller JOSHCLAY. Stuvia facilitates payment to the seller.

Will I be stuck with a subscription?

No, you only buy these notes for $10.99. You're not tied to anything after your purchase.

Can Stuvia be trusted?

4.6 stars on Google & Trustpilot (+1000 reviews)

83637 documents were sold in the last 30 days

Founded in 2010, the go-to place to buy study notes for 14 years now

Start selling
$10.99
  • (0)
  Add to cart