Muscle slide Q's Flashcards
(34 cards)
What are the functions of muscle tissue
- Movement
- Stabilization
- Organ volume
- Moving substances through the body
- Heat
- Storage of food
what are the properties of muscle tissue
- Electrical excitability
- Contractility
- Extensibility
- Elasticity
Smooth muscle features
- Spindle
- Single Nuclei
- Not striated
- Involuntary
- E.g. intestine wall
Cardiac muscle features
- Branching
- Single Nuclei
- Visible striations
- Involuntary
- E.g. heart
Skeletal muscle features
- Elongated
- Multiple Nuclei
- Visible striations
- Voluntary
- E.g. skeletal muscle
Muscle composition
- Water = 75%
- Protein = 20%
- Salts and other substances = 5%
Order of the skeletal muscle layers
- Muscle
- Fascicles
- Individual muscle fibres
- Myofibrils
- Actin and myosin (myofilaments)
what covers the fascicles?
Perimysium
what covers the individual muscle fibres
Endomysium and the sarcolemma
What covers the entire muscle
Epimysium
What does the sarcoplasmic reticulum store
Ca2+
Why does the sarcolemma have T Tubules
Allow the muscle action potential to spread to all parts of the muscle quickly.
What is fascia
It is a sheet or band of fibrous connective tissue that surrounds muscles and other organs of the body
What are langer’s lines
Skin creases that reflect the fibre orientation of the fascia and muscles that lie below
What is the thin filament structure made up of
Actin, troponin and tropomyosin.
What is the thick filament made up of
Myosin
What does tropomyosin do?
Blocks the ‘binding’ site at rest
What does troponin do?
Supporting structure for tropomyosin and changes shape when in contact with a calcium ion therefore the actin and myosin can bind and contract the muscle.
What muscle fibre angle produces the most force?
short, slanted fibers therefore large diameter
What muscle fibre angle produces the most velocity?
Long, straight fibers therefore small diameter.
How many actin filaments surround a myosin filament?
6
What axes goes through the belly button?
Sagittal
What axes goes through both iliac crests?
Frontal
What axes goes through the top of your head downwards?
Longitudinal