Class Notes (837,827)
Canada (510,504)
Physiology (645)
PSL300H1 (220)
Lecture

Lecture 23 - Muscle Contraction

3 Pages
65 Views
Unlock Document

Department
Physiology
Course
PSL300H1
Professor
Michelle French
Semester
Fall

Description
L23 Nov 09 11Voltagegated Ca2 channels in ttubulesMuscle Contractionmaintains act pot get influx into sarcoplasmSR membrane right up against ttubulehas Muscle action potentialanother set of voltagegated Ca2 channelsAct pot generated in muscle fibers is same as in 2 ways of couplingaxons except longer duration 5 msSome physically joinedSR channel opened Travel from NMJ to both ends of fibreby t channelAct pots invade ttubules at regular intervals Ca2 itself binds to SR Ca2 channelsthroughout fibretriggers conformational changeCa2 moves to sarcoplasm net Ca2 from SR into sarcoplasmsliding filament mechContractile proteinsActinmyosin molecs arranged in alternating overlapping bands clusters form sarcomere unit of myofibrilsbanding patternMyosin head sticks out side of filamentforms crossbridge when attached to binding sites on actin molecBinding sites for myosin spaced 36 nm apart Ttubules meander across muscle fibresall the way along actin filamentSR mesh sac btwn ttubules store Ca2Thick filament in pumped incentremyosin Large cisternae along sides of ttubulesheads sticking out in Contractile prots
More Less

Related notes for PSL300H1

Log In


OR

Join OneClass

Access over 10 million pages of study
documents for 1.3 million courses.

Sign up

Join to view


OR

By registering, I agree to the Terms and Privacy Policies
Already have an account?
Just a few more details

So we can recommend you notes for your school.

Reset Password

Please enter below the email address you registered with and we will send you a link to reset your password.

Add your courses

Get notes from the top students in your class.


Submit