The Krause membrane or $Z$-line is a structure in a myofibril that separates two adjacent:

Between two successive $M$-lines,there is/are:

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.

The immediate source of energy for muscle contraction is ...... .

Contraction of a muscle is caused by

Which of the following are the special properties of muscles?