Exam 3 chapter 14 Flashcards
Functions of bones include
Support for soft tissues and organs, protection of organs such as brain and spinal cord, body movement, and hematopoiesis.
Bones are continually?
Remodeling and changing the collagen and mineral composition to accommodate stress place on them.
The function of each bone dictates its shape and surface features
For example, long bones act as levers; they have a flat surface for the attachment of muscles, with grooves at the end for passage of tendons or nerves. Long bones are: humerus, femur, fibula, and phalanges. Short bones are carpal and tarsal bones are cube shaped. Flat bones make up the cranium, ribs, and scapula. The vertebrae are irregularly shaped bones.
The human skeleton has two major divisions:
The axial and appendicular skeletons. The axial skeleton includes the facial bones, auditory ossicles, vertebrae, ribs, sternum, and hyoid bone; the appendicular skeleton includes the scapular, clavicle, bones of the shoulders and arms, and bones of the pelvis and legs. The subsequent discussion of bones is organized by these divisions
Skeletal muscles
Composed of muscle fibers that attach to bones to facilitate movement. Some move by reflex, all are controlled voluntarily. Fibers are arranged parallel to the long axis of bones to which they attach, or they are attached obliquely. Muscles attach to a bone, ligament, tendon, or fascia
Joints are articulations where two or more bones come together. They help hold?
The bones firmly while allowing movement between them.
Joints are classified in two ways:
By the type of material between them (fibrous, cartilaginous, or synovial) and by their degree of movement
- immovable joints are synarthrodial (e.g. the suture of the skull)
- slightly moveable joints: amphiarthorodial (e.g. the symphysis pubis)
- freely moveable joints: diarthrodial (e.g. the knee and the distal interphalangeal (DIP) joint of the distal fingers)
Diarthrodial joints
Freely moveable joints and are further classified by their type of movement.
-these joints have one or more ranges of motion
pivot joints permit movement of?
one bone articulating with a ring or notch of another bone such as the head of the radius, which articulates with the radial notch of the ulna
hinge joints
(e.g. knee, elbow, fingers) permit extension and flexion. Some hinge joints allow hyperextension. Variability among individuals; not all hinge joints are able to hyperextend
Condyloid or ellipsoidal joints consist of the?
Condyle of one bone that fits into the elliptically shaped portion of its articulating bone (e.g. the distal end of the radius articulates with three wrist bones)
Ball and socket joints
Made of a ball-shaped bone that fits into a concave area of its articulating bone (e.g. the head of the femur fits into the acetabulum within the pelvis)
Gliding joints
Permit movement along various axes through relatively flat articulating surfaces such as joints between two vertebrae
Diarthrodial joints are
Synovial joints because they are lined with synovial fluid.
- this fluid lubricates the joint to facilitate its movement in various directions
- some synovial joints such as the knee also have a disk called the meniscus, which is a pad of cartilage that cushions the joint. These joints have a covering surrounding them called the joint capsule, which is an extension of the periosteum of the articulating bone. Ligaments also encase the capsule to add strength.
Difference between ligaments and tendons
Ligaments: strong, dense, flexible bands of connective tissue that hold bones to bones. Provide support in several ways: encircling the joint, gripping it obliquely, or lying parallel to the bone ends across the joint. Can simultaneously allow some movements while restricting others
Tendons: strong, nonelastic cords of collagen located at the ends of muscles to attach them to bones. Support bone movement in response to skeletal muscle contractions, transmitting remarkable force at times from the contracting muscles to the bone without sustaining injury themselves
