Skeletal system: Difference between revisions

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[[Image:Vertebral column.png|250px|thumb|right|Human vertebral column]]
[[Image:Vertebral column.png|250px|thumb|right|Human vertebral column]]
The '''skeletal system''' has many different functions that are necessary for vertebrates to survive. It provides support for the overall body. It offers a place for muscle and tendons to attach. It provides a great amount of protection for the vital organs inside of the creature. Movement is also helped by the skeletal system, which adds leverage for increased range of motion. And finally, the bones of the skeletal system continuously produce blood cells.
The '''skeletal system''' has many different functions that are necessary for vertebrates to survive.  


== Joints ==
'''Main Functions:'''
There are four different primary joints located throughout the body. These are the hinge, the ball and socket, the picot, and the glide joints. The each serve different purposes, and are located in areas best suited for those purposes.
It provides support for the overall body.  
 
It offers a place for muscle and tendons to attach.  
=== Hinge ===
It provides a great amount of protection for the vital organs inside of the creature.  
The hinge joint is basically a hinge. It can move up and down or from side to side, but within a 180<sup>o</sup> range. A very common example of this is a person's elbow or knee. Hinge joints usually have a lot of stress placed on them, and the knee is a very common example of this. Knee surgery is more common than any other surgery performed on a joint, because they are used rigorously each day. They are the joints that move you up, down, forward, and they have to carry all of your weight. This stresses the knee joint so much that it is not uncommon for even an average person to damage them in some way.
It adds leverage for increased range of motion.  
 
Bones of the endoskeletal system continuously produce blood cells.
=== Ball and Socket ===
[[Image:Shoulder.gif|250px|thumb|left|The shoulder is an example of a ball and socket joint]]
 
The ball and socket joint allows for increased range of movement. The best examples of this type of joint are the shoulder and hip joints. Even though the shoulder is considered a ball and socket joint, the hip is considered the most "true" ball and socket joint because the ball is almost completely enclosed by the socket. The shoulder is more like a ball resting inside of a shallow dip, rather than being fully encompassed. This does, however, offer increased mobility and range, at the cost of being easier to pop out of joint or being injured. Shoulder problems are very common because of this joint structure. In fact, 13.7 people in the United States had treatment for shoulder-related problems in 2003.[http://www.pueblo.gsa.gov/cic_text/health/shoulderqa/shoulderqa.htm]


=== Pivot ===
== Exoskeleton
The pivot joint allows for the most movement out of all of the joints. The most common example of this joint is the neck, which can look from side to side, up and down, and almost any way at all. This joint is used primarily to be able to see your surroundings without turning your whole body. This helps when you are driving or carrying large objects, but other than that, there is little else that it can do.
[[Image:Spider-skin.jpg|thumb|150px|thumb|An empty carcass of a [[spider]]]]


=== Glide ===
The glide joint is similar to the ball and socket joint in terms of the range of movement, but there is no actual ball and socket. An excellent example of this is a person's wrist, which has extreme mobility but no bulky ball and socket like the shoulder. Glide joints are also very delicate, and can be easily damaged. They are also very weak, and cannot apply very much  force by themselves. For example, try lifting a 30 lb weight with your whole arm, and then try lifting the same weight using just your wrist. Gliding joints are useful, but lack a lot of support that allows other joints to apply more force.


== Bone Types ==
== Endoskeleton ==
=== Bone Types ===
[[Image:Compact and Spongy.jpg|thumb|350px|right|Diagram of the spongy and compact layers of the bone]]
[[Image:Compact and Spongy.jpg|thumb|350px|right|Diagram of the spongy and compact layers of the bone]]


There are three different types of bone in the skeletal system. These are the outer layer of the bone, the compact middle layer, and the spongy third layer.
There are three different types of bone in the skeletal system. These are the outer layer of the bone, the compact middle layer, and the spongy third layer.


=== Periosteum ===
==== Periosteum ====
The periosteum is hard and smooth. It provides protection to the rest of the layers of the bone. It is almost like the "skin" of the bones. The periosteum provides a site for the attachment of muscles, and also contains nerves, blood vessels, and lymphatic vessels.[http://www.estrellamountain.edu/faculty/farabee/biobk/BioBookMUSSKEL.html]
The periosteum is hard and smooth. It provides protection to the rest of the layers of the bone. It is almost like the "skin" of the bones. The periosteum provides a site for the attachment of muscles, and also contains nerves, blood vessels, and lymphatic vessels.[http://www.estrellamountain.edu/faculty/farabee/biobk/BioBookMUSSKEL.html]


=== Compact ===
==== Compact ====
The compact bone is extremely dense and surrounds the spongy bone. The compact bone also contains many Haversian canals, which also contain nerves and blood vessels. This layer of bone gives the skeleton its strength and allows it to support your bodies mass.[http://webschoolsolutions.com/patts/systems/skeleton.htm]
The compact bone is extremely dense and surrounds the spongy bone. The compact bone also contains many Haversian canals, which also contain nerves and blood vessels. This layer of bone gives the skeleton its strength and allows it to support your bodies mass.[http://webschoolsolutions.com/patts/systems/skeleton.htm]


=== Spongy ===
==== Spongy ====
The spongy bone is where all of the blood cells are created from the bone marrow. Spongy bone contains two different types of bone marrow: red and yellow marrow. The red bone marrow produces red and white blood cells and platelets. The yellow bone marrow, however, is used to store fats.[http://webschoolsolutions.com/patts/systems/skeleton.htm]
The spongy bone is where all of the blood cells are created from the bone marrow. Spongy bone contains two different types of bone marrow: red and yellow marrow. The red bone marrow produces red and white blood cells and platelets. The yellow bone marrow, however, is used to store fats.[http://webschoolsolutions.com/patts/systems/skeleton.htm]
=== Main Groups ===
====Axial====
====Appendicular====
=== Joints ===
There are four different primary joints located throughout the body. These are the hinge, the ball and socket, the picot, and the glide joints. The each serve different purposes, and are located in areas best suited for those purposes.
==== Hinge ====
The hinge joint is basically a hinge. It can move up and down or from side to side, but within a 180<sup>o</sup> range. A very common example of this is a person's elbow or knee. Hinge joints usually have a lot of stress placed on them, and the knee is a very common example of this. Knee surgery is more common than any other surgery performed on a joint, because they are used rigorously each day. They are the joints that move you up, down, forward, and they have to carry all of your weight. This stresses the knee joint so much that it is not uncommon for even an average person to damage them in some way.
==== Ball and Socket ====
[[Image:Shoulder.gif|250px|thumb|left|The shoulder is an example of a ball and socket joint]]
The ball and socket joint allows for increased range of movement. The best examples of this type of joint are the shoulder and hip joints. Even though the shoulder is considered a ball and socket joint, the hip is considered the most "true" ball and socket joint because the ball is almost completely enclosed by the socket. The shoulder is more like a ball resting inside of a shallow dip, rather than being fully encompassed. This does, however, offer increased mobility and range, at the cost of being easier to pop out of joint or being injured. Shoulder problems are very common because of this joint structure. In fact, 13.7 people in the United States had treatment for shoulder-related problems in 2003.[http://www.pueblo.gsa.gov/cic_text/health/shoulderqa/shoulderqa.htm]
==== Pivot ====
The pivot joint allows for the most movement out of all of the joints. The most common example of this joint is the neck, which can look from side to side, up and down, and almost any way at all. This joint is used primarily to be able to see your surroundings without turning your whole body. This helps when you are driving or carrying large objects, but other than that, there is little else that it can do.
==== Glide ====
The glide joint is similar to the ball and socket joint in terms of the range of movement, but there is no actual ball and socket. An excellent example of this is a person's wrist, which has extreme mobility but no bulky ball and socket like the shoulder. Glide joints are also very delicate, and can be easily damaged. They are also very weak, and cannot apply very much  force by themselves. For example, try lifting a 30 lb weight with your whole arm, and then try lifting the same weight using just your wrist. Gliding joints are useful, but lack a lot of support that allows other joints to apply more force.


=== Broken Bones ===
=== Broken Bones ===
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