Muscle Tissue Function Flashcards
What are the 3 different forms of muscle?
- Skeletal
- Cardiac
- Smooth
Name a striated and a non-striated muscle
Striated - Skeletal, Cardiac
Non-Striated - Smooth
What is Myoglobin? Which molecule does it interact with?
- Molecule with high O2 affinity
- Receives oxygen from haemoglobin
- Released when striated muscle dies
What are the four layers of skeletal muscle from inner to outer?
- Muscle fibre
- Fasicle of Endomysium
- Perimysium
- Epimysium
What prefix relates to skeletal muscle?
Sarco
In which direction does skeletal muscle move?
Along the direction of a fibre
What are myofibrils?
Building blocks of muscle fibres
What two bands are present in myofibrils and what colour are they?
I-Band is light
A-Band is dark
Which 2 types of filament form a myofibril and what is their function?
- Actin and Myosin
- Make the basic contraction machinery
What is the name of the skeletal muscle unit that falls between 2 Z-Lines?
Sarcomere
Name 3 differences between slow twitch and fast twitch fibres
Slow Twitch - rich capillary supply, aerobic, many mitochondria and cytochromes, red, fatigue resistant, used for endurance
Fast Twitch - poor capillary supply, anaerobic, few mitochondria and cytochromes, white, rapidly fatigue, used for strength
Name 3 characteristics of cardiac muscle
- Central nuclei
- Have intercalated discs
- Branched
- Made of cardiomyocytes
- Endocrine
- Communication through gap junctions
What are Purkinje fibres and where are they located?
- Large cells which conduct action potentials to allow contraction
- Between Endocardium and Myocardium
What is the pathway of conduction through the heart?
SA node > AV node > Atria Contract > AV bundle > Intraventricular septum > Right/Left bundle branches > Purkinje fibres > Ventricular walls
Name 3 characteristics of smooth muscle
- Spindle-shaped cells
- Single, large central nucleus
- Stretchable
- Respond to stimuli - nerves/hormones
- Form sheets, bundles or layers
