Identify the incorrect statement regarding muscle contraction.

Which of the following activities occurs at the site labeled $P$ in the given diagram of a myosin monomer?

The dark band present on a myofibril is known as:

Select the correct statements regarding the mechanism of muscle contraction.
$A.$ It is initiated by a signal sent by $\text{CNS}$ via a motor neuron,not a sensory neuron.
$B.$ Neurotransmitter generates an action potential in the sarcolemma.
$C.$ Increased $Ca^{++}$ level leads to the binding of calcium with troponin on actin filaments.
$D.$ Masking of the active site of actin prevents contraction; unmasking leads to contraction.
$E.$ Utilising the energy from $\text{ATP}$ hydrolysis to form a cross-bridge.

How does a muscle shorten during its contraction and return to its original form during relaxation?

$ATP_{ase}$ activity is found in: