A-Level Biology AQA 7402

6.3: Skeletal muscles are stimulated to contract by nerves and act as effectors

#6.3.1

Muscles act in antagonistic pairs against an incompressible skeleton.

#6.3.2

Gross and microscopic structure of skeletal muscle. The ultrastructure of a myofibril.

#6.3.3

The roles of actin, myosin, calcium ions and ATP in myofibril contraction.

#6.3.4

The roles of calcium ions and tropomyosin in the cycle of actinomyosin bridge formation. (The role of troponin is not required.)

#6.3.5

The roles of ATP and phosphocreatine in muscle contraction.

#6.3.6

The structure, location and general properties of slow and fast skeletal muscle fibres.

6.2.2

Synaptic transmission

6.4.1

Principles of homeostasis and negative feedback