Muscular System

Muscle Fibers Contraction – pulls attachments together Relaxation – stretch to normal position. Muscle is the tissue that makes up the heart, body organs, and skeletal muscles. At a microscopic level, muscle fiber is simply cells grouped together to form a muscle. Muscle accounts for about half of the body’s weight. All muscles function the same way, in a movement known as contraction. They pull attachments closer together. During muscle relaxation, they stretch back to normal position, and require energy to create movement.

Voluntary and Involuntary Involuntary muscles consist of the cardiac muscle and smooth muscle. The cardiac muscle makes up the heart and is found only in the heart. This muscle receives electrical signals to assist in contraction. The coordinated contractions allow for the heart to pump blood out of the atria and ventricles to the blood vessels. This muscle relies on blood and electrical supply to deliver oxygen and nutrients. The next muscle, call the smooth muscle is found throughout the body in the form of blood vessel walls, stomach, small and large intestines, and the bladder. This type of muscle tissue is also found in lymphatic vessels, urinary bladder, uterus, and male and female reproductive tracts. This one could be split into cardiac and smooth. The voluntary muscles consists of skeletal muscles which control the movements we consciously perform, such as lifting objects, running, sitting, and brush our teeth. It also plays an important role in maintaining the body’s body posture and position. Muscles are categorized into two types, voluntary and involuntary. You consciously contract or control voluntary muscles and involuntary muscles cannot be consciously controlled. Let’s take a look at each type.   Maybe not the greatest layout—I was thinking images and buttons onscreen, and then definitions appear over images when buttons are rolled over or clicked on.

Movement Remove labels, make them drag and drop to match to pictures. Body movements are important indicators of range of motion, injuries, and illness. Decreased range of motion sometimes occurs with age, but may also be due to injury. Match each type of movement to the correct illustration.

Upper Body Muscles You use a number of major skeletal muscles on a daily basis. Many of the muscle names indicate their locations. For example, the temporalis muscle is located near the temples or temporal lobe. Match the labels with the corresponding muscles. Remove labels, make them drag and drop to match to picture.

Lower Body Muscles The muscles of the lower body are generally larger than those in the upper body. This makes sense when you consider that they provide support for the entire body, and that the types of movements they are responsible for (such as running and jumping) require more muscle. Match the labels with the corresponding muscles. Remove labels, make them drag and drop to match to picture.

Bones work in conjunction with muscles to create movement Bones work in conjunction with muscles to create movement. Muscles can only contract when there is movement. The opposing forces of muscles throughout the body, especially our limbs, create the power to lift, grab, and run. Involuntary muscles operate by electric signals from your brain for contraction on its own, while voluntary muscles function when you raise your arm, kick a ball, or lift an object, you are performing the movement. So it’s always important to have a good dose of daily exercise and water to keep your muscles in top shape!