Skeletal Muscle Contraction (Sliding Filament Theory) Flashcards
What is Skeletal Muscle made up from?
Muscle Fibres
What is the Basic Functional unit of muscle fibre?
Sacromeres
What Myofilaments are contained in the Sacromere.
Actin & Myosin
What does Sliding filament theory explain?
How muscles contract.
At resting state what is Actin & Myosin’s formation?
Overlapped but not interacting.
When a Nerve signal (action potential) reaches the muscle what is released from the sacroplasmic reticulum?
Calcium Ions.
Where are calcium ions released from in a muscle?
Sacroplasmic reticulum
What do Calcium Ions bond to once released?
Troponin Molecules on the actin filament.
What moves due to the conformational change in Troponin?
Tropomyosin Moves.
When Tropomyosin moves what is exposed on the Actin filament?
Myosin binding sights.
What is formed when myosin binds to actin?
Cross bridges.
What causes the myosin heads to move once bonded to the actin?
ATP Hydrolysis.
What happens to the Sacromere as the myosin heads repeatedly bind, move and release the actin.
It shortens as the actin slides over the myosin.
What two things occur once a nerve signal ceases within the muscle.
Calcium ions are actively transported back to the sacroplasmic reticulum.
Tropomyosin returns to its original position on the actin.
