Sliding Filament Theory

Question 1

1. Brain

Answer 1

Process sensory information and then transmits the action via a motor neuron to the site of contraction

Question 2

2. NMJ (Neuromuscular Junction)

Answer 2

Signal arrives at the nerve ending close to the muscle fibre that will contract

Question 3

3. ACH (Acetylcholine)

Answer 3

ACH is released from the nerve ending and binds with receptors on the surface of the sarcolemma

Question 4

4. Calcium

Answer 4

Action potential rushed into the cell and causes calcium to be released from sarcoplasmic reticulum➡️calcium can now bind with troponin

Question 5

5. Cross-Bridge and Powerstroke

Answer 5

• Cross-Bridge = Myosin heads can now attach to the active sites on the actin filament
• Power-Stroke = Myosin head tilts and drags the actin in the opposite direction (needs ATP)

Question 6

6. Contraction Ends

Answer 6

If there is no stimulus received in the brain the muscle will return to rest

Question 7

H Zone

Answer 7

• At the centre of the A band of each sarcomere
• Only thick filaments

Question 8

Z Line

Answer 8

The area at each end of seperate sarcomeres where the actin filaments are attached

Question 9

A Band

Answer 9

• The active area where contraction takes place between the actin and myosin filaments.
• Contains thick filaments

Question 10

I Band

Answer 10

• The region between adjacent A bands, each band extends across two sarcomeres
• Only thin filaments