100% satisfaction guarantee Immediately available after payment Both online and in PDF No strings attached
logo-home
Previously searched by you
Previously searched by you
logo
Psych 439 Final Exam Review with Questions and Answers CA$11.60   Add to cart
Quickly navigate to
Preview
  2.  
  3. Psych 439
  4.  
  5. Psych 439

Exam (elaborations)

Psych 439 Final Exam Review with Questions and Answers
 0 view  0 purchase
  • Course
  • Psych 439
  • Institution
  • Psych 439

Psych 439 Final Exam Review with Questions and Answers presynaptic terminal ANSWER contains neurotransmitter-filled vesicles and machinery to release them (dumped into that space when signal arrives) postsynaptic region ANSWER includes on or more postsynaptic densities (PSDs) that are opposit...

[Show more]

Preview 3 out of 26  pages

Document information

  • November 15, 2024
  • 26
  • 2024/2025
  • Exam (elaborations)
  • Questions & answers

Subjects

  • psych 439 final exam review with questions and ans

Written for

  • Psych 439
  • Psych 439

Seller

avatar-seller
wangithiannaw

Reviews received

Content preview

Psych 439 Final Exam Review with
Questions and Answers
presynaptic terminal ANSWER contains neurotransmitter-filled vesicles and machinery to
release them (dumped into that space when signal arrives)



postsynaptic region ANSWER includes on or more postsynaptic densities (PSDs) that are
opposite to the presynaptic terminal's active zone; receptors to receive signal



synaptic cleft ANSWER the area between two components filled with extracellular matrix,
composed of a variety of long-chain molecules that polymerize with one another (e.g.,
collagen, laminin, fibronectin)



3 stages of synapse maturation ANSWER 1. Initial contact - filopodia try to contact the
target, increased adhesion is the first level of specificity. First contact is mediated by
adhesion molecules like cadherins.

2. Assembly of synaptic machinery - synaptic vesicles start forming and the receptors start to
line up.

3. Stabilization of synapse - mature synapses are stabilized by the PSDs and weaker synapses
are pruned away. If they are stabilized, they are here to stay.



NCAM ANSWER a cell adhesion molecule that helps cells grip to surfaces - generally
stickiness to help them stay at the target



Cadherins ANSWER the 1st level of specificity; hemophilic specificity helps axons and
targets display some discrimination; activation of each induces further differentiation



Beta-catenin ANSWER links the intracellular domain of the cadherin receptor to actin
filaments inside the cell in order to anchor the synapse

,cadherin-beta-catenin complex is important for pruning of dendritic spines because the beta-
catenin is in short supply so it is competed over

Strongest spines get the most beta-catenin and so they are the ones that remain



What does a wider dendritic spine indicate? ANSWER more receptors available to receive
signal so there is a stronger synapse there



Fragile X Syndrome ANSWER an X-linked disorder that is caused by a trinucleotide repeat
(CGG), this repeats causes the X chromosome to become weak and break off; over
production of beta-catenin (used for pruning away weaker synapses) which results in a lack
of competition. Weak synapses will stay around and this causes motor deficiencies or
intellectual disabilities

Shows that more is not always better.



neurexin ANSWER inductive factor made by the growth cone; engages in cell-to-cell
signaling by binding to the neuroligin on the postsynaptic side. Important for vesicular
release and neurotransmitter release from presynaptic cells.

It helps set up SNARE complex and synaptotagmins,



Neuroligin ANSWER Inductive factor produced by the postsynaptic cell - where the ligand
binds.

Involved in scaffolding and anchoring PSD proteins so that all of the necessary proteins for
signaling are present underneath the presynaptic terminal.



What facilitates the maturation of the myotubes into muscle fibers? ANSWER arrival of the
motor neuron axonal growth cone



Where are ACh receptors located on muscle? ANSWER top of junctional folds in clusters,
nearest the axon terminal

, Where are AChE found in muscle? ANSWER in deep junctional folds



Steps to set up NMJ ANSWER 1. ACh continuously released by incoming growth cone that
will innervate the muscle cell, and the myotube expresses AChRs that respond to the NT
(ACh) - 1st step in a series of signals between the axon terminal and its target

2. Agrin is released by growth cone and binds to Lrp4

3. Binding of agrin to Lrp4 causes dimerization and autophosphorylation of internal domain
of MUSK

4. MUSK activates rapsyn

5. Rapsyn binds the intracellular domains of several AChRs and anchors them to the
microtubule of the muscle cell - this is why they are only found clustered under the synaptic
cleft

6. Neuregulin is released by the presynaptic cell and induces the muscle cell to express
certain subunits of AChR



agrin ANSWER a proteoglycan that is released from the growth cone and serves as a signal
and inductive factor at the NMJ; how we keep the AChRs anchored at the synapse instead of
floating around the bilayer



Neuregulin ANSWER A family of proteins that are motor neuron factors which induce
muscles to increase transcription of the various subunits of AChR at that NMJ; embedded in
motor neuronal axon membrane (can act via cell-cell contact); can be released but only
remain local

Bind to ErbB kinases on muscle fibers which boosts expression of AChR subunits



What drives depolarization in embryonic neurons? ANSWER influx of Ca2+ ions through vg
Ca2+ channels drives action potentials

NOT Na+ influx!

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 wangithiannaw. Stuvia facilitates payment to the seller.

Will I be stuck with a subscription?

No, you only buy these notes for CA$11.60. You're not tied to anything after your purchase.

Can Stuvia be trusted?

4.6 stars on Google & Trustpilot (+1000 reviews)

75632 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
CA$11.60
  • (0)
  Add to cart