Muscles And Bones Flashcards
Bones and muscles homeostasis
- movement in responding to stimuli
- digestion of food
- protection, structure
- b: store/release calcium for muscle contraction, blood clotting, nerve impulse conduction
- m: maintain constant body temp.
Tendon
Connective tissue
Origin: attachment of muscle on stationary bone
Insertion: attachment of muscle on bone that moves
Action: antagonistic vs synergistic
A: muscles that work in opposite pairs
S: muscles working in groups for common action
Fascicles
Muscle fibres arranged in bundles
myofibrils
Bundle of myofilaments that run the length of a finer
Myofilaments
2 main proteins (actin + myosin) arranged in repeating units
Sarcomeres
Repeating units of actin and myosin found along a myofibril
Myoblasts
Precursor cells
Satellite cells
Mature muscles have these that serve as stem cells for this tissue
Myosin
Composes the THICK filaments shaped like a golf club
- motor protein, uses ATP for movement
Actin
composes THIN filaments (microfilaments)
- slides over one another during muscle contraction
How do you move muscles?
Step 1/3
1: nerve pulses travel down to motor neurons to a NEUROMUSCULAR JUNCTION (NMJ)
How do you move your muscles 2/3
neurotransmitter acetylcholine (ACh) released by exocytosis from neurons -> binds to receptors on muscle fibres
How do you move your muscles 3/3
Binding stimulates fibres (signal transduction) causing Ca2+ released from sarcoplasmic reticulum
Motor unit
Nerve + muscle fibre
