What job do muscles do?

                      Muscles are needed for all body movements. Muscles move the bones, pulling them into position as they move about their joints. Some muscles just move soft parts of the body, for example, the face muscles that allow you to smile.

                      You can control many of your movements by using voluntary muscles. Other muscles, called involuntary muscles, work automatically to maintain the body. The heart, for instance, beats without your being aware of it. The muscles that squeeze your food along inside the intestines also work automatically.

How are muscles joined to bone?

                     Muscles are attached to bone by long ropy strands called tendons, which are made of collagen. You can feel these tendons on the inside of your wrist when you flex your hand and fingers.

How are muscles constructed?

                    Muscles are built up from millions of thread-like cells called muscle fibres. These fibres are gathered into bunches. Nerves instruct the muscle fibres when to shorten, or contract, causing the whole muscle to become shorter in length. The shortened muscle then pulls on the tendon and the bone to which it is joined.

Pictures Credit: Google