Understanding the Body's Muscular System: Structure and Movement

Muscles

Muscles are tissues that contract and relax to move the body. They are attached to bones by tendons, and when they contract, they pull on the bones to move them. There are three types of muscles: skeletal muscles, smooth muscles, and cardiac muscles.

* Skeletal muscles are voluntary muscles that are attached to bones. They are responsible for all of the body's voluntary movements, such as walking, running, and talking.

* Smooth muscles are involuntary muscles that are found in the walls of organs such as the stomach, intestines, and blood vessels. They are responsible for controlling the automatic functions of the body, such as digestion and respiration.

* Cardiac muscles are involuntary muscles that are found in the heart. They are responsible for pumping blood throughout the body.

The human body has over 600 muscles, which makes up about 40% of the body's total weight.