Week 13: (A) Coupling and Skeletal Muscle Contraction Flashcards
What are the 3 types of muscle function?
skeletal, cardiac, smooth
What is the primary function of the muscle?
generate force of movement in response to physiological stimulus
Transduce chemical or electrical signal to a mechanical response
What needs to increase for all muscle types to contract?
increase [Ca2+]i
What muscle type will we focus on?
skeletal
What does skeletal muscle contract in response to?
neuromuscular synaptic transmission
How many NMJ does a skeletal muscle fibre have?
1 - single
What receptors are on skeletal muscle post synaptic neurone?
nAChR
What inactivates ACh
AChE
What 3 main structures make up a skeletal muscle
Epimysium, perimysium, endomysium
What is the location of a muscle fibres in the muscle?
There are many muscle fibres in each fascicle surrounded by an endomysium
What does the muscle fibre contain?
“sacs” called myofibrils
What do myofibrils contain?
myosin and actin
What is the endomysium?
surround each and every muscle fibre
What 2 bands does myosin have?
I band & A band
What is the light band?
I band
What is the dark band?
A band
What filaments are in the A band?
myosin & actin
What is the thick filament in A band?
myosin
What is the light filament in A band?
actin
what defines the sarcomere?
smallest component of a muscle that can contract
Where is the M line located?
down the centre of the sarcomere
What band is on either side of the sarcomere?
Z line, I band
What filament surrounds the thick filament?
thin filament (actin)
What is the gap of muscle next to the A band in the sarcomere?
I band (light)
What line runs in between of the A and I bands?
Z line
what filament is surrounded by thin filament?
thick filament (myosin)
What line connects 2 actin filaments of sarcomeres?
Z line
