Muscles AO2 Flashcards
What are the functions of the skeleton?
Protect
Movement
Support
Types of muscles:
Cardiac-(heart tissue)
Strained/skeletal -(muscles under conscious control. Pretend attached to bone)
Smooth/involuntary-(controlled by the nervous system)
What are bones attached
Bones are joined to bone by ligaments
How are muscles joined to bone?
Muscles are joined to bones by tendons
What is flexion?
Bending
What is extension?
Opposite of flexion- straightening
How do muscles work?
In antagonistic pairs
Where does a motor neurone connect to the muscle to a specialised set of synapses.
Motor end plate
What is a muscle?
A muscle is an organ made up of different tissues
What are muscles made up of?
Muscles are made up of muscle fibres
What are muscle fibres packed with?
Myofibrils
What are myofibrils?
Myofibrils are made up of two muscles filaments called actin and myosin
What are myofibrils divide functional units called?
Sarcomere
How do muscles contract?
- Tropomyosin blocks actin-myosin binding site
- Ca2+ binds to tropomyosin, pulling it out of the way
- myosin head is able to bind with actin-myosin filament
- Ca2+ activates ATPase (enables head to move)
- ATP binds to head (changes shape)
- ATP hydrolysed, head returns to shape
- when stimulation stops Ca2+ is pumped back into the sarcoplasmic reticulum (muscle relax)
Types of muscles
cardiac - muscle tissue in heart
smooth or involuntry- controlled by the automated nervous system, E.g. blood vessels
striated or skeletal- under conscious control. attached to the bone and enable movement.
what is cartilage
- acts as a lubricant between bones to stop them from rubbing.
- connective tissue in joints
what are tendons?
they are connective tissue that transmit mechanical force of muscle contraction to the bones.
what is the role of calcium?
- stops myosin head from binding to binding site
- nerve impulses cause calcium ions to be released
- makes the tropomysin change shape
- calcium ions bind with the troponin
name the different actin filaments
H band
I band
A band
Z line
what are slow twitch fibres
- designed for aerobic exercise
- resistant to fatigue, muscle contracts are slow
- Higher capacity of aerobic respiration
- marathon runners and swimmers use these
- high levels of myoglobin
- lots of muscle contraction in a short period of time
how is phosphate creatine regenerated in aerobic respiration?
Phosphate creatine is regenerated from ATP at rest.
how is ATP made?
phosphate creatine is broken down and gives its energy which releases phosphate ions which is makes ATP.
