Smooth and skeletal muscle Flashcards
function of muscles in the body
contractions and relaxation in order to create movement
skeletal muscle function
contraction/relaxations (shortening/lengthening) to create movement or stabilise body position
limb movement, speech, chewing, heat
smooth muscle function
create movement within the body
air, blood, fluid, food/bowel movement
What types of muscles are striated?
Skeletal and heart
Is skeletal muscle voluntary or involuntary?
Voluntary
Is smooth muscle voluntary or involuntary?
Involuntary
Is cardiac muscle voluntary or involuntary?
Involuntary
What do ions and ionic currents establish?
Resting plasma membrane potential- excitable cells
What is an action potential?
Brief change in resting membrane potential
What is the function of myofilament reconfiguration and sarcomere shortening?
Contraction and relaxation in order to create movement
What is skeletal muscle contraction/relaxation for?
Create movement or stabilise body position- limb movement, speech, chewing, heat
What is smooth muscle contraction/relaxation for?
Create movement within the body- air, blood, fluid, food/bowel movement
What is the function of muscles?
To contract and relax in order to create movement
What makes muscles contract?
Excitation-Contraction Coupling
Where are myofilaments?
Inside the sarcomeres
How does acetylcholine activate create movement in skeletal muscle?
Ach-ach stimulate action potential in muscle fibre
How do smooth muscle move?
Neurotransmitters from neuron varicosities diffuse into cells
What causes an action potential?
Movement of ions across plasma membrane
What channels are opened at action potential peak?
Calcium
What does Ca2+ trigger?
Myofilament contraction
How Ca 2+ removed from myofilaments
Via Ca2+ pump and removed from the cell by plasma membrane
What happens when Ca2+ leaves myofilament?
Myofilament relax
What is required for myofilament contractiom?
Ca2+ and ATP
