MSK Histo Flashcards
Where are slow twich muscles found in abundance?
Postural muscles
3 features of type 1 a muscles
Type 1: Slow twitch muscle fibres are found in highest numbers in postural muscles. The fibres contain large mitochondria that lie in rows between the myofibrils. Alongside them are fat droplets that the mitochondria use as a source of triglyceride for the production of ATP. Type 1: Slow twitch muscle fibres are oxidative in terms of energy supply, are fatigue resistant and are found in highest numbers in postural muscles.
Which of the following statements about Type 2A muscle fibres is TRUE?
They are fast twitch fibres
They are the predominant fibre type in the muscles of the back
They contain numerous large mitochondria
They derive their energy solely from glycolysis
They fatigue easily
Type 2A: Fast twitch muscle fibres use a mixture of both oxidative & glycolytic processes to obtain their energy and are moderately fatigue resistant. Compared with slow twitch muscles these fibres have fewer and smaller mitochondria but contain large reserves of carbohydrate in the form of glycogen that they utilise in the production of ATP.
