What is the primary function of muscle tissue?
To produce movement
What are the 3 different types of muscle tissue?
What is the only non-striated type of muscle tissue and is it also the only involuntary one?
Smooth muscle tissue and no Cardiac muscle is also involuntary
What is the breakdown of skeletal muscle tissue from outside to in? Covering(...)
Epimysium(muscle), Perimysium (Fasicles), Endomysium(muscle fibres) Sarcoplasmic reticulum(myofibrils)
What are myofibrils made up of?
Sarcomeres consisting of the myofilaments myosin(thick) and actin(thin)
What is the difference between the I band and the A band?
I band is light
A band is dark
What is the difference betwen the z line and the m line?
They are both protein rings that support structure, but Z line separates sarcomeres and is in I band and M line is in middle of A band
What are the 4 steps of a muscle contraction? with details
Nervous impulse arrives at neuromuscular junction, that causes Acetylcholine to be released which depolarises motor end plate causing this message to be sent down transverse tubules to sarcoplasmic reticulum, which then releases calcium.
Once calcium is released it attaches to troponin causing tropmyosin to move out of the way of the myosin head attaching to the actin head to form a cross bridge.
The breakdown of ATP alllows the myosin head to contract and pull actin head, simulateneously shortening I band and H band(band inside of A band). To repeat an ATP molecule binds to myosin, breaking cross bridge, then once it has been broken down myosin reattaches and pulls.
Acetylcholinesterase breaks down acetylcholine, sarcoplasmic reticulum re-absorbs calcium and tropomyosin covers the actin. While the I band and H band lengthen.
What is the role of myoglobin in muscle contraction and how does it help us differentiate between skeleta muscle fibre types?
Myoglobin is a protein that oxygen binds inside the muscle, providing an extra reserve of oxygen for longer lasting activites. Myoglobin content also determines colour of muscle i.e. slow muscle twitch fibres of type1 are red (full), while super fast twitch fibres of type 2a are white(emtpy)