muscle structure and adaption Flashcards
how do muscle fibres “grow”
they grow in diameter postnatally - they don’t increase in number
number of muscle fibres is determined genetically.
what is the bare zone
where actin filaments sit
what is the order of MHC isoforms that can split ATP the fastest first (5)
2B > 2A > 2X > 1 > embryonic
what is the slowest contracting isomer
type 1
what is the fastest contracting isomer
type 2B
What do satellite cells do
divide to form a myoblast and fuse with existing fibres
what is released from pituitary gland?
GH which goes to liver and stimulates IGF - 1 (insulin like growth factor)
what does IGF - 1 also do
protein synthesis
what is the relationship between motion units and difficulty of task
the harder the task the larger the motor unit that will innervate that muscle type.
