THE SKELETAL SYSTEM: BONE STRUCTURE AND
CLASSIFICATION
Although bones appear lifeless, they are alive, and like any
other cell in the body, they require food and oxygen to live.
Water actually makes up ________________ of a bone’s total
mass. The rest of the bone is made up of ________________ , such
as calcium and phosphorus, as well as a protein called
collagen. The minerals provide ________________ for the bones,
while the protein gives the bone ________________ .
This means that if the bone was low in minerals it would be
very ________________ and ________________ easily. If they were
low in protein then the bones would just ________________
under any pressure. Bone is a very strong structure but is
quite ________________ . This works out well because the
muscles are not equipped to support ________________
skeletons.
There are ________________ different types of bones in the body.
Each name gives you an indication of what that bone may
look like. The five different types of bones are ________________,
short, flat, ________________ bones and sesamoid.
Long Bones
Long bones are ________________ , dense bones. They provide
________________ , structure and ________________ . A long bone has
a shaft and two ends. Long bones contain ________________
bone marrow and ________________ bone marrow, which
produced red blood cells. Examples of long bones include;
the ________________ , humerus and radius.
Short Bones
In humans, are ________________ in shape. The length, width
and height measurements are all about the ________________ .
Short bones include; the ________________ and tarsals.
Flat Bones
Made up of a layer of ________________ bones between two thin
layers of ________________ bones. Their shape is ________________ ,
not rounded. Flat bones have ________________ , but not a bone
marrow cavity. They protect vital ________________ or are
attachments sites for large ________________ . Examples of flat
bones include; the ________________ and ribs.
Irregular Bones
Have a non-uniform shape. As such, they do not fall into any
other category. They consist of ________________ bone, with a
thin layer of ________________ bone. Examples of irregular
bones include the ________________ bones and vertebrae.
Sesamoid Bones
Is a bone embedded within a ________________ . They are found
where tendons ________________ over a joint. This bone causes
the tendon to be situated ________________ away from the joint
and as such ________________ the movement arm. They also
prevent the tendon from ________________ into the joint as
tension ________________ .
THE SKELETAL SYSTEM: JOINTS AND ANATOMICAL TERMS
There are three different types of joints. They are called:
–______________ Joints
–______________ Joints and
–______________ Joints
The joints are classified based on their ______________ of
movement.
Fibrous Joints
Occur where bones are ______________ . There is ______________
movement. For example: the ______________ and pelvis.
Cartilaginous Joints
Occur where bones are united by intervening ______________ .
They have ______________ movement. For example: the ribs or
the ______________ .
Synovial Joints
______________ moveable joints. Are directly involved in
producing skilled ______________ . For example: knee and
______________ .
Characteristics of Synovial Joints
______________ movement in at least one direction. Has
cartilage that aids in ______________ and cushioning. Have
ligaments that ______________ bone in place and allow
______________ range of movement. Enclosed by a joint
______________ (a synovial membrane that secretes
______________ fluid which promotes ______________ movement).
Types of Joints
- Saddle Joint: Allows ______________ , backwards and
______________ movement. Example: ______________ of
thumb.
- Hinge Joint: Has only ______________ axis and allows only
______________ and extension. Examples: ______________ ,
knee, fingers and toes.
- Pivot Joint: Has 1 ______________ and allows only one
______________ . Example: ______________ at spinal column.
- Ball and Socket Joint: Able to move in ______________
directions. Example: Hip and ______________ .
- Gliding Joint: Allows side, back and ______________
movement. Example: Wrist and ______________ .
Anatomical Terms
•Flexion: joint angle is ______________ .
•Extension: joint angle is ______________ .
•Abduction: movement ______________ from the midline of the
body.
•Adduction: movement ______________ the midline of the body.
•Pronation: rotation of the wrist ______________ , so palm is
facing ______________ .
•Supination: rotations of the wrist ______________ , so the palm
is facing ______________ .
•Medial rotation: rotation towards the ______________ of the
body.
•Lateral rotation: rotation ______________ from the midline.
•Inversion: rotation of the foot ______________ . Sole is faced
______________ .
•Eversion: rotation of the foot ______________ . Sole is faced
______________ .