Muscle Types

A muscle is an organ that can contract in a coordinated fashion and includes muscle tissue, blood vessels, nerves, and connective tissue. Some of the major muscles of the human body are shown in Figure 45-9. Recall that the human body has three types of muscle tissues: skeletal, smooth, and cardiac.

Skeletal muscle is responsible for moving parts of the body, such as the limbs, trunk, and face. Skeletal muscle tissue is made up of elongated cells called muscle fibers. Each muscle fiber contains many nuclei and is crossed by light and dark stripes, called striations, as shown on the following page in Figure 45-10a. Skeletal muscle fibers are grouped into dense bundles called fascicles. A group of fascicles are bound together by connective tissue to form a muscle. Because their contractions can usually be consciously controlled, skeletal muscles are described as voluntary muscles.




Pectoralis major

Triceps brachii

Biceps brachii

Latissimus dorsi

Abdominal muscles

Gluteus maximus

Sartorius Biceps femoris

Rectus femoris Gastrocnemius Achilles tendon

figure 45-9

31 Days To Bigger Arms

31 Days To Bigger Arms

You can have significantly bigger arms in only 31 days. How much bigger? That depends on a lot of factors. You werent able to select your parents so youre stuck with your genetic potential to build muscles. You may have a good potential or you may be like may of the rest of us who have averages Potential. Download this great free ebook and start learns how to build your muscles up.

Get My Free Ebook

Post a comment