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Rib cage

life science Maturity 9-11 Next article →

Your rib cage is a vital part of your skeleton. It is also called the thoracic cage. This structure acts like a protective enclosure for your chest. It guards important organs like your heart and your lungs. It also protects your great vessels. The cage helps support your shoulder girdle too.

Gray122
Gray122

The rib cage works by moving as you breathe. It contains muscles that help you inhale and exhale. These are called the muscles of respiration. One important muscle is the diaphragm. Other muscles are the intercostal muscles. These sit in the spaces between your ribs. These spaces are called intercostal spaces. They hold nerves, arteries, and veins.

ribcage during inhalation
ribcage during inhalation

Most humans have a specific set of bones. A typical human thoracic cage has 12 pairs of ribs. These ribs connect to the vertebral column in your back. They also connect to the sternum in the front. The sternum is a long, flat bone. The top part of the sternum is the manubrium. It has a U-shaped border called the jugular notch.

Gray122
Gray122

We can group the ribs into three different types. The first seven pairs are the true ribs. They connect directly to the sternum using costal cartilage. The next five pairs are called false ribs. They do not connect directly to the sternum. The eleventh and twelfth ribs are called floating ribs. These ribs only attach to your vertebrae. They do not touch the sternum at all.

Skeleton woman back
Skeleton woman back

Your rib cage begins to form while you are an embryo. It grows from a layer called the mesoderm. Tiny structures called somites help make the ribs and vertebrae. At first, the ribs are made of cartilage. This cartilage slowly turns into bone through endochondral ossification. In males, the rib cage can expand during puberty. This happens because of a hormone called testosterone. This helps males inhale more air for their muscles.

Skeleton woman back
Skeleton woman back
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🖼️ Images & Media (5)
File:Gray122.png
Gray122.png
File:Skeleton woman back.png
Skeleton woman back.png
File:C7ribMark.png
C7ribMark.png
File:ribcage during inhalation.jpg
ribcage during inhalation.jpg
File:Wankel Tyrannosaurus cast rib cage UCMP.JPG
Wankel Tyrannosaurus cast rib cage UCMP.JPG
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