Skeletal System Flashcards
how many bones are in the adult body?
206
What does the axial skeleton consist of?
80 bones, including
-the skull,
-vertebral column
- thoracic cage
what does the appendicular skeleton consist of?
all bones of the upper and lower limbs, including the pectoral and pelvic girdles
-126 bones
The axial skeletal forms the _________and _______ axis of the skeletal system
vertical and central
Types of Bone
-flat bone
-Irregular Bone
-sesamoid bone
-long bone
-short bone
function of flat bone
have a flattened broad surface and provide protections such as the skull and sternum.
function of short bones
provide specialized movements such as with carpal and tarsal bones in hands and feet, respectively
function of irregular bones
serve as sources of muscle attachment and movement provision
function of sesamoid bones
serve as a source of tendon and muscle attachment and movement provision
function of short bones
serve as a source of tendon and muscle attachment and movement provision
diaphysis
the long shaft of a long bone
Within the diaphysis of the bone is a hollow canal known as the _____________
medullary cavity
Prior to each enlarged end of the diaphysis is the __________
metaphysis
Each enlarged end of the bone is called the _________
epiphysis
epiphyseal disk
-structure in the epiphysis hat is active prior to skeletal maturity in the early to mid-20s.
-known as the growth plate
What is the function and location of articular cartilage?
-located at the tip of the epiphysis
-protects the bone surface and provide cushioning at freely movable joints such as the hip, knee, and shoulder
periosteum
the membranous covering on the outer surface of a long bone
The osseous bone tissue of the long bone is composed of two types:
compact and spongy bone
compact bone
-also known as cortical bone
-hard, thick, and dense osseous tissue that provides structural support and protection
The majority of the diaphysis is composed of ________
compact bone
what parts of a long bone are comprised of spongy bone?
The inner lining of the medullary cavity and the bone tissue at the epiphyses
spongy bone
also known as cancellous bone, is softer than compact bone because the bone matrix is much less dense.
Connective tissues are characterized by
a dense fibrous intercellular matrix with relatively few cells comprising the matrix, such as fibroblasts, macrophages, and mast cells
Which connective tissues are avascular?
-cartilage
-tendons
-ligaments
What are the different types of connective tissue?
loose connective tissue,
-adipose tissue,
-dense fibrous connective tissue
-elastic connective tissue,
-cartilage,
-osseous tissue (bone)
-blood.
function of cartilage
-unites the bone of cartilaginous joints, covers the articular surface of bones comprising freely movable synovial
-provides the framework for developing bones during the process of endochondral ossification
How does cartilage get blood?
Most of the blood supply to cartilage comes from diffusion from blood vessels that are located in the perichondrium (a fibrous connective tissue that covers cartilage).
Hyaline cartilage
- semi-transparent and appears bluish-white in color
-strong but flexible and elastic
-reduces friction at joints, supports joints, stabilizes and facilitates joint movement
Where does hyaline cartilage occur?
occurs in the trachea, larynx, tip of the nose, the connections between the ribs and the sternum, and also the ends of bone at the articular surface of joints.
Fibrocartilage
-collagenous bundles that take up a direction parallel to the cartilage
-extremely tough
where does fibrocartilage occur?
-found as discs between the vertebrae,
- between the pubic bones in front of the pelvic girdle at the pubic symphysis,
-and around the edges of the articular cavities such as the glenoid cavity in the shoulder joint, forming the glenoid labrum.
function of fibrocartilage
shock absorption, provides joint stability without impeding movement, and provides joint stability by deepening the articular fossa.
elastic cartilage
-similar to hyaline cartilage, but in addition to the collagenous fibers, the matrix of the elastic also contains an abundant network of branched yellow elastic fibers.
-runs through the matrix in many directions
-maintains shape
where does elastic cartilage occur?
the lobe of the ear, epiglottis and in parts of the larynx
What are the two Subtypes of connective tissue?
Loose and Regular
Regular dense connective tissue
-has the collagen fibers aligned parallel to each other, so that it has a strong unidirectional resistance to stress
-makes up tendons and ligaments
What are the subtypes of dense connective tissue?
-dense regular and dense irregular
joints are also known as…
articulations
tendon vs ligament
-TENDONS connect MUSCLE to BONE
-LIGAMENTS connect BONE to BONE
what makes up the majority of the fibers of the extracellular matrix (ECM) within dense connective tissue?
collagen fibers
How are joints classified structurally?
-fibrous (no joint cavity/capsule), -cartilaginous (no joint cavity/capsule),
and
-synovial (joint cavity/capsule).
How are joints classified functionally?
-synarthrodial (immovable), -amphiarthrodial (slightly movable)
and
-diarthrodial (freely movable).
synarthrodial
immovable
amphiarthrodial
slightly movable
diarthrodial
freely movable
which structural joint types have no joint capsule/cavity?
The fibrous and cartilaginous joints
Symphysis joints
cartilaginous joints formed by a fibrocartilage disk that units two bones, such as the symphysis pubis and intervertebral joints.
synchondrosis joints
cartilaginous joints where hyaline cartilage unites two bones as is found in the epiphyseal disks (growth plates on long bones).
synovial joint
-diarthrodial
-has capsule
-6 different types of diarthrodial joints
6 types of diarthrodial joints
-planar arthrodial joint
-pivot trochoid joint
-hinge ginglymus joint
-saddle, sellar joint
-ellipsoid or condyloid joint
-ball and socket, enarthrodial joint
what is bone tissue comprised of?
osteoblasts (immature bone cells), osteocytes (mature bone cells), and osteoclasts (specialized cells which degrade bone tissue).
What hormones impact longitudinal growth?
-growth hormone (GH)
-insulin growth factor 1 (IGF-1)
-oxytocin
what impacts appositional (diameter) growth?
-growth hormone
-parathyroid hormone (in very tiny intervals)
The major systemic regulators in bone remodeling are:
PTH, calcitriol, GH, glucocorticoids, thyroid hormones, and testosterone and estradiol
why is bone remodeling systemic?
it involves hormones and is impacted by axial loading
