Involuntary muscles are

Which of the following interacts with skeletal muscles to produce movement?

Which of the following is a contractile protein of muscle?

Which protein is distributed at regular intervals on the tropomyosin protein?

Muscle is attached to bone by

Select the correct option for skeletal muscle.
$(I)$ In human body,it is made of a number of muscle bundles.
$(II)$ Muscle bundles contain a number of muscle fibers and each fiber is lined by the sarcolemma.
$(III)$ In a muscle fiber,the sarcoplasm contains only one nucleus.
$(IV)$ In a muscle fiber,the sarcoplasmic reticulum is the storehouse of calcium ions.