Rib Cage 3/3/14

Kaylee Hennessey
5 March 2014
Period A

Rib Cage

Medical Art Studio

2011

Summary of the Article

The rib cage is located in the center of the body and is part of the axial skeleton. It has three major functions:

• protection
• support
• respiration

It encloses and protects the heart and lungs. The rib cage also provides support for the back and vertebral column, as well as other bones like the shoulder girdle. It expands and contracts with respiration, due to the fact that it attaches to the diaphragm.

Bones of the Rib Cage

• sternum

               flat bone made of the manubrium, body,                    and xiphoid process

• 12 thoracic cavities

               thoracic vertebrae T1-T12.

• 12 pairs of ribs

               bones 1-7 are attached to the sternum and are called "true ribs". 8-10 are false ribs, and 11 and                    12 are floating ribs.

Bone Development and Growth

Kaylee Hennessey

January 20, 2014

Period A

Bone Development and Growth

Dawn A. Tamarkin, PhD.

STCC Foundation Press

2011

Summary of the Article:

There are two different ways for bones to develop:

-embryonically: cells differentiate from other cells and grow to form organs and tissues.

-postembryonically: any type of development changes that occur after one is born.

The term for the formation of bones is ossification. Most bones start off as cartilage and then grow to bone. This is an example of endochondral ossification. 

Embryonic Development

Intramembranous Ossification 

Intramembranous ossification occurs within a membrane and produces a flat type of bone.

Connective tissues form in sites where intramembranous bones will eventually be formed. The connective tissues possess a high amount of blood cells, which form spongy bone. Connective tissues harden, and compact bone is formed.

Endochondral Ossification

In this type of ossification, bone forms by replacing hyaline cartilage.

Chondrocytes within the cartilage begin to die. At that time, a periosteum forms around the cartilage. It produces osteoblasts, which build between and around the spongy bone. Compact bone begins to form from the osteoblasts.