What are 5 functions of the skeleton?
1. provides a supporing framework for the body
2. provides attachment ponts for muscles, creating a lever system that enables body movement
3. provides protection of vital organs
4. Blood cell formation- i.e. red bone marrow produces red and white blood cells and platelets
5. Mineral storage-calcium and phosphorus
What are the 4 major building blocks of bone?
1. calcium carbonate
2. calcium phosphate
3. collagen fibers
What is bone tissue composed of? What is it surrounded by?
Widely separated cells, called osteocytes, surrounded by
matrix. The matrix is about 25% water, 25% protein, and 50% mineral salts.
Bone is highly ________ and is continually being remodeled in response to
_________ ______ or even absence of stress.
dynamic, mechanical stress
The bones of ________ ______ individuals tend to be denser and therefore more
_________ than those of sedentary individuals of the same age and gender
physically active, mineralized
What are long bones?
Long bones are longer than they are wide. The hollow shaft of these bones is made of compact bone, being filled with yellow marrow.The ends of long bones are composed of spongy or cancellous bone which contains red marrow.
What are short bones?
They are composed of spongy bone covered by a shell of compact bone. i.e. wrist (carpals) and ankle (tarsals)
What are flat bones?
Bones that have a broad surface for muscle attachment or protection of underlying organs. i.e. face, skull, scapula, ribs
What does the vertebral column provide?
Flexible support for the trunk and protects the spinal
The vertebrae articulate with one another by means of facets on the processes of the
_______ _______ (synovial joint) and by means of ___________ _____ between the
vertebral bodies (cartilaginous joint).
neural arches, intervertebral discs
What do invertebral disc function as?
shock absorbers and allow slight movement so that the
column is flexible and resilient
What are the 2 functions of synovial fluid?
1. Lubricates the joint surfaces as they slide over each other during joint movement
2. Supplies nutrients to, and removes waste products from the cartilage cells which have no direct blood supply
What is the frontal plane?
divides body into anterior and posterior portions, passes through side to side
What is the sagittal plane?
divides the body into right and left sides, passes through body from front to back
What is the transverse plane?
divides the body into superior and inferior portions, passes through body dividing into an upper and lower half
What is flexion?
a movement that results in a decrease in the angle between 2 bones i.e. when you bend the elbow joint
What is extension?
The reverse of flexion. It is when a body part returns to its anatomical position.i.e. straightening the elbow from the flexion position.
What is rotation?
the motion of a bone around a central axis.
Inward (medial) rotation- bone moves inward
Outward (lateral) rotation- bone moves outward
What is supination?
lateral (outward) rotation of the forearm which brings the palm of the hand upward
What is pronation?
medial (inward) rotation of the forearm which brings the palm of the hand downward
What is elevation?
movement that results in a portion of the body being lifted upwards i.e. lifting the shoulders to shrug
What is depression?
movement that results in a portion of the body being lifted downwards - opposite to elevation
What is a sprain?
twisting or over stretching a joint causes a ligament to be stretched beyond its normal limits or even separated from it bony attachment
What is dislocation?
the articular surfaces of bones that are forcibly displaced
i.e. the shoulder and knee joints are most vulnerable to dislocation
What is arthritis?
joint inflammation caused by trauma, bacterial infection, metabolic disorders, or other unknown causes
What are 4 structural limits to flexibility?
1. Bony structure of the joint - can't be changed by a flexibility program
2. Ligaments- fibrous tissues that attach bones to each other
3. Joint capsules
4. Muscle-tendon unit - muscle and its fascial sheaths - the major focus of stretching exercises is the elongation of this tissue.