Sierra College Department of Biological Sciences

Discover the Biological Sciences

The introductory information for this site has been contributed as a joint assignment by students in Bio. Sci. 10.

Anatomy - Skeletal System

By: Molly Beatty

Human Anatomy: Skeletal System
The field of biology that I have chosen to research is Human Anatomy. I will focus my topic on the skeletal system and show why it is so important for humans and animals to have bones.

According to an online dictionary the skeletal system is defined as, “The bodily system that consists of the bones, their associated cartilages, and the joints, and supports and protects the body, produces blood cells, and stores minerals.”

I found that the skeletal system is more than just ‘bones’. It also involves how they move, hold together and support and protect the body. Something else that could be studied is how the skeletal system is closely related to the circulatory system. On the inside of bones red and white blood cells are made and then sent throughout the body. Another aspect one could study about is bone and joint diseases such as osteoporosis and arthritis. These diseases affect millions of people and doctors and scientist are always looking for new medicines and procedures to find a cure.

One major concept for the skeletal system is the anatomy of bones. There many bones in the human body but only 5 different types. The 5 types are long bones, short bones, flat bones, irregular bones, and sesamoid bones. Long bones are longer than they are wide and an example of one is the femur (upper leg bone). Short bones are small and usually have the same length and width. They are found in hands and feet and some examples of short bones are tarsals and carpals. Flat bones are found on the skull. They are thin so they can curve around and protect the brain. Irregular bones are ones with a unique shape and size that are unlike other bones. The vertebra column is a great example of irregular bones because when looking at them they have a distinctive irregular shape all to their own. Finally, sesamoid bones are enclosed in tendons and are found in areas that have a lot of physical stress and tension. An example of a sesamoid bone is the patella (knee cap). Knowing more about the anatomy of bones helps to understand why they are shaped and placed in a certain way.

The most interesting fact that I found when studying the skeletal system is that babies are born with about 300 bones in their body. Over time they fuse together and when they are done growing there is a total of 206 bones in the human body. Also, of those 206 bones more than half of them are found in hands and feet.

“Health and Body: Dem Bones” 9 September 2007. <>
“Skeletal System.” The American Heritage® New Dictionary of Cultural Literacy, Third Edition Copyright 2005 by Houghton Mifflin Company. <>
“Types of bones.” 2003. 9 September 2007. <>

Additional Information Websites: (National Osteoporosis Foundation)

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