Exam (elaborations)
MCBM 2 - Excitatory Cells Questions with 100% Correct Answers
- Course
- Institution
MCBM 2 - Excitatory Cells Questions with 100% Correct Answers
[Show more]
Content preview
1 of 187Definition
NMJ
Give this one a try later!
connection between sensory electrical synapse between two
neurons and the brain neurons
chemical synapse between a
junction between two cardiac
motor neuron and the muscle
muscle cells
, it innervates
Don't know?
2 of 187
Definition
excitable cells
Give this one a try later!
those capable of developing action potentials across their plasma
membranes. They can do this because they express voltage-gated cation
channels in specific membrane domains (e.g., muscle)
gap junctions (electrically couple the muscle cells of the heart) + desmosomes
("spot weld" the cells together so they don't pull apart when the heart contracts)
tropomyosin binds to actin, blocking myosin binding site, but there is no troponin
in smooth muscle (other calcium binding proteins are involved in regulating
smooth muscle
striations less obvious as in skeletal muscle; individual cardiac cells may branch
(unlike other muscle cells); cells electrically coupled via gap junctions
Don't know?
3 of 187
,Definition
what do epinephrine and norepinephrine lead to
Give this one a try later!
the myosin head cannot release from actin until it binds a new ATP. This stage
(low energy myosin bound to actin) is known as rigor, as in the rigor mortis
associated with death (the cells very quickly use up all available ATP when it dies
and as the membrane looses viability, a depolarization induces an action
potential and contraction, but no ATP is available to release myosin from actin).
increase in heart rate by decreasing the degree to which Vm is repolarized
(so Vm starts closer to threshold) and increases the rate at which Vm
spontaneously depolarizes. So the Vm gets to threshold in a shorter
amount of time and thus you see an increase in the frequency of action
potentials per unit time
both contraction and relaxation require the presence of ATP. Contraction also
requires calcium. tension does not develop in a muscle previously exposed to
calcium until ATP is added. If you remove ATP before calcium the muscle stays
contracted (it is in its rigor phase); but it will stay contracted even if you take
away calcium at this point (remember, ATP is still lacking). Not until ATP is added
back in does the muscle relax (in the absence of calcium)
The open RyR calcium release channel allows a rapid flux of calcium ions from
the SR lumen into the cytoplasm (down the electrochemical gradient for
calcium). This flood of calcium into the cytoplasm induces muscle contraction.
Don't know?
4 of 187
, Definition
Give this one a try later!
multi: no; single: no sarcolemma
image 8 image 9
Don't know?
5 of 187
Definition
desmosomes
Give this one a try later!
a complex of 3 subunits that binds
act to hold cardiac cells
to actin periodically along the
together
filament
duration of the calcium signal (up to
end-to-end sarcomeres in series
some period of time)
The benefits of buying summaries with Stuvia:
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
You can quickly pay through credit card or Stuvia-credit for the summaries. There is no membership needed.
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 codersimon. Stuvia facilitates payment to the seller.
Will I be stuck with a subscription?
No, you only buy these notes for $8.00. You're not tied to anything after your purchase.
Can Stuvia be trusted?
4.6 stars on Google & Trustpilot (+1000 reviews)
73314 documents were sold in the last 30 days
Founded in 2010, the go-to place to buy study notes for 14 years now