Muscles Flashcards
(38 cards)
What connect tissue around muscle
Epimysium
What connects tissue around fascicles
Perimysium
What’s a fascicles
Group of muscle cells
What does the endomysium do
Connect tissue around the muscle cell
What’s the sarcolemma
It’s muscle cell plasma membrane
What are myofibrils made up of
Sarcomeres
What is a sarcomere
It is composed of protein filament of myosin and act to function the muscle
What are essential ingredients for a muscle to contract
Action potential Calcium ATP ACTIN Myosin
What is the sliding filament theory
Is the explanation for how muscle contact to produce force
What are the 3 stages of the sliding filament theory
Creation of cross bridge
Sliding of the filament
Muscle relaxation
What’s happens is the creation of the cross bridge stage of sliding filament theory
Thin actin filaments have binding sited where myosin five red want to attach to them
What happens in the 2nd stage of the sliding filament theory
Myosin heads swivel and pull actin filaments towards the middle of the sarcomere.
This shortens the whole sarcomere
ATP then bind ps myosin head to detach
then the process repeats as long as there is calcium and ATP available
What happens in the muscle relaxation stage of the sliding filament theory
Calcium removed from sarcoplasm
ATP is no longer used by muscle cell
Tropomyosin complex covers the binding sites
Muscle relaxes
What are thick filaments
Two proteins strands each folded into a globular head at one end
What does thick filaments contain
500 myosin molecules
What are thin filaments
Twisted combination of actin Tropomyosin and troponin with one end attached to a Z disk
What does the Z disc do?
Separates the sarcomeres
What is the M line
Supports proteins holding the thick filaments
What’s the H line
Thin filaments but no thick filaments
What’s the A line
Thick filaments length
What attaches the fascia to the bone
Tendon
What’s a unipennate muscle
When all the fibres are on the same side
What is a example of unipennate muscle
Ex. Biceps femoris , extensor digitorum long us , tibialis posterior
Where is a pennate muscle
Rectus femoris
