Skeletal Muscle Physiology 2 Flashcards
Dr S Khogali
skeletal muscle tension is dependant on 2 factors. what are they?
number of muscle fibres contracting and tension developed by each fibre
in skeletal muscle, the duration of twitch is much shorter than the duration of reaction potential
true or false?
false
the duration of action potential is much shorter than the duration of resulting twitch
what is evoked when the motor nerve that innervates a skeletal muscle emits action potentials at a very high rate?
tetanus
what muscle type cannot be tetanised?
cardiac muscle due to refractory period
what is produced if skeletal muscle is stimulated once?
a twitch
The tension developed by skeletal muscle increases with increasing frequency of stimulation
true or false?
true
Maximal tetanic contraction can be achieved when the muscle is at its _______ ______ before the onset of contraction
optimal length
name the 2 types of muscle contraction
isotonic contraction
isometric contraction
what is isotonic contraction used for?
body movements and moving objects
what is isometric contraction used for?
supporting objects in fixed position and posture
in which type of contraction does the muscle length change?
isotonic contraction
outline 3 ways metabolic pathways supply ATP in muscle fibre
from creatine
oxidative phosphorylation
glycolysis
when do we get ATP from glycolysis?
when O2 is not present
name the 3 types of muscle fibres
type I
type IIa
type IIx
what are type I fibres aka?
slow oxidative
slow twitch
