bones, skeleton and joints Flashcards
what are the 6 functions of bones?
- support - bones provide the hard framework that supports the weight of the body
- movement - skeletal muscles attach to bones and use them as the levers to move
- protection - e.g. the cranial bones protect the brain
- mineral storage - bones are reservoir for minerals, importantly calcium and phosphate
- blood cell formation and energy storage - red bone marrow makes red blood cells (hematoposis) yellow bone marrow stores fat
- energy metabolism - osteoblasts secrete osteocalcin (plays a role in blood sugar regulation)
what are osteoblasts ?
cells that actively produce the bone matrix
what are osteocytes ?
keep bone matrix healthy, maintain bone matrix
what are osteoclasts ?
break down bone matrix
what are the four classifications of bone shape?
and provide examples
long - humerus
short - talus
flat - sternum
irregular - vertebrae
what is the periosteum?
a connective tissue membrane that cover the entire outer surface of each bone except on the ends
what is a tuberosity ?
large rounded projection
what is a crest?
narrow ridge of bone; usually prominent
e.g. the lilac crest of the hip bone
what is a line ?
a narrow ridge of bone less prominent than a crest
what is a tubercle ?
small rounder projection or process
what is a head?
boney expansion carried on a narrow neck
what is a facet?
smooth, flat articular surface
what is a meatus?
canal -like passageway
e.g. the external and internal auditory meatus on the temporal bone
what is a fossa?
a shallow basinlike depression in a bone
what is a sinus?
cavity within a bone, filled with air and lined with mucous
what is the name given to the formation of bone-tissue?
osteogenesis and ossification
what is endochondral ossification?
the process in which hyaline cartilage is replaced with bone matrix
what are the five steps of endochondral ossification?
- a bone collar forms around the diaphysis
- cartilage calcifies in the centre of the diaphysis
- the periosteal bud invades the diaphysis and the first bone tracbeculae forms
- diaphysis elongates and the medullary cavity forms
- epiphyses ossify and cartilaginous epiphyseal plates separate diaphysis and epiphyses
what is the epiphyseal plate?
between diaphysis and epiphysis
aka the growth plate
responsible for lengthening
bones during the two decades following birth
what are the five zones of the epiphyseal plate/growth plate?
reseting zone
profliferation zone - chondroblasts at the top divide quickly pushing diaphysis anway from epiphysis, elongating the bone
hypertrophic zone - older chondrocytes in the stack enlarge and send signal to calcify
calcification zone - cartilage matrix becomes calcified
ossification zone
bone deposition is accomplished by ….
osteoblasts
bone resorption is accomplished by ….
osteoclasts
what is the most complex bony structure ?
the skull
what are the cranial bones/cranium/skull cap ?
there are 8 cranial bones, these bones enclose and protect the brain occipital sphenoid parietal (2) temporal (2) ethmoid frontal
what are the four large sutures of the cranium?
the coronal suture (where parietal bones meet frontal bone) squamous suture (occurs where each parietal bone meets the temporal bone inferiorly) sagittal suture (where the left and right parietal bones meet) lambdoid suture (occurs where parietal bones meet the occipital bone posteriorly )
which bone houses the foramen magnum ?
the occipital bone
foramen magnum is the large hole of the inferior aspect
where are the occipital condyles and what do they articulate with ?
the occipital condyle are located lateral to the foramen magnum and articulate with the superior articular facets of the atlas
where is the sphenoid bone? and what are some key features
remember the sphenoid bone when looking at the skull anteriorly it looks like a butterfly
it articulates with each of the other cranial bones
It consists of a central body and three pairs of processes; the greater wings, lesser wings and pterygoid processes
Structures that form the vertebral arch are __________ and __________.
lamina and pedicles of a vertebra
Parts of which bones form the middle cranial fossa?
sphenoid and temporal bones
Which bones of the skull contain paranasal sinuses?
frontal,
ethmoid,
maxillae, and
sphenoid bones
Most of the articulation of which structures enable the head to nod up and down (that is, to nod “yes”)?
occipital condyles and superior articular facets of the atlas vertebra C1
Bones that develop between the major skull bones, particularly between the occipital and parietal bones, are ______bones.
sutural
Mastoid air cells are located in the mastoid process of the_______ bone
temporal
Why is the sphenoid bone considered the “keystone” of the cranium?
It articulates with every other cranial bone.
The jugular foramen is an opening for the internal jugular vein and which other structure(s)?
cranial nerves IX, X, and XI
The _____ bone of the axial skeleton does not articulate directly with any other bones.
hyoid
The bones that articulate with the frontal bone superiorly, the perpendicular plate of the ethmoid posteriorly, and the maxillae laterally are the ______ bones.
nasal
The inferior part of the nasal septum is formed by the ____
vomer
The ____ nasal conchae form part of the lateral walls of the nasal cavity, but are not part of the ethmoid bone.
inferior
The posterior part of the hard palate and a small portion of the nasal cavity and orbit walls are formed by the _______ bones.
palatine
what thoracic vertebra do not have a transverse costal facet
T11 and T12
do all cervical vertebrae have intervertebral discs located between them ?
no C1 and C2 do not have them
The manubrium of the sternum articulates with the body of the sternum at the __________.
sternal angle
which bones does the zygomatic bone articulate with?
maxilla shenoid bone frontal bone temporal bone parietal bone
The first rib has what unique characteristic(s) when compared to other ribs?
It has grooves on its superior surface for the subclavian artery and vein.
and
It is flattened from superior to inferior.
The thoracic and sacral curvatures of the spine are the ____ curvatures.
primary
present at birth
what are the three sections of the sternum?
manubrium, body and xiphoid process
where is the jugular notch?
superior border of the manubrium
what is the sternal angle?
where the manubrium joins the body of sternum
The ____ of a rib articulates with the transverse process of the thoracic vertebra of the same number as the rib.
tubercle
A vertebra has thin, tapered transverse processes and a blunt, rectangular posteriorly facing spinous process. It is a
____ vertebra.
lumbar
what is scoliosis and what may it result from ?
an abnormal lateral bending of the vertebral column
abnormally structured vertebrae
lower limbs of unequal length
what is a secondary curvature?
cervical curvature - when a baby starts to lift head
lumbar curvature - when toddler starts to walk
what does the thoracic cage include ?
12 pairs of ribs, the sternum and the thoracic vertebrae
what does the sternum consist of and what are the important landmarks ?
maniubrium, body and xiphoid process
landmarks; jugular notch, sternal angle and xiphisternal joint
characteristics of ribs?
typical ribs consist of a head with facets, a neck, a tubercle and a shaft and costal cartilage occurs on the ventral end of each rib
The sternal angle of the sternum is __________.
a good landmark for finding the second ribs
what does the appendicular skeleton consist of ?
the pectoral and pelvic girdles and the bones of lower and upper limb
what do the pectoral girdles consist of?
a clavicle, a scapula and attaches an upper limb to the thoracic cage
what does each clavicle articulate with?
each clavicle articulates with the manubrium (sternoclavicular joint) medially and a scapular lateral (acromioclavicular joint)
purpose of clavicles?
the clavicles hold the arms laterally away from the thorax and transmit pushing forces from the upper limbs to the thorax
what bones does the scapular articulate with?
a clavicle (acromioclavicular joint) and a humerus (glenoidhumeral joint
what bone comprises the arm ?
humerus
what are the bones of the forearm ?
radius (lateral) and ulna (medial)
what bones make up the pelvic girdle ?
two hip bones and sacrum which form the pelvis
what are the characteristics of the hip bones?
ilium, ischium and pubis which are fused together, the region which they are fused is the acetabulum
what is the ilium ?
is the superior flaring part of the hip bone. The ilium forms a joint with the sacrum.
what is the ischium ?
It is a curved bar of bone . When sitting weight is borne by the ischial tuberosity
what does the pelvic inlet consist of ?
the pubic crest, arcuate line of ilium and sacral promontory.
Difference between female and male pelvis?
male pelvis is relatively deep and narrow, with larger, heavier bones
female pelvis (which forms the birth canal is comparatively shallower and wider)
what is the only bone of the thigh?
the femur
what done does head of the femur articulate with ?
the acetabulum (socket of hip bone) to form the hip joint
what are the bones of the leg ?
tibia (which participates in both knee and ankle joints) which is located medially and the slender fibula which is located laterally
what are the bones of the foot?
tarsals, metatarsals and phalanges
The most important tarsals are the calcaneus (heal bone ) and the talus (which articulates with the leg bones at the ankle joint)
what are the functional classifications of joints ?
synarthrosis (no movement)
amphiarthrosis (limited/slight movement)
diarthrosis (free movement)
what are the structural classifications of joints?
fibrous
cartilaginous
synovial
characteristics of fibrous joints?
in fibrous joints the bones are connected by fibrous connective tissue, no joint cavity
nearly all fibrous joints are synarthrotic (immovable)
what are the types of fibrous joints ?
sutures
syndesmoses (ligament joints)
gomphoses (teeth with sockets)
what are the characteristics of cartilaginous joints ?
bones are united by cartilage and not joint cavity exists
what is an example of a cartilaginous joint ?
epiphyseal plates
fibrocartilage joints - intervertebral discs and public symphysis
what is the general structure of synovial joints ?
fluid filled joint cavity
covered by articular capsule
what types of movements are allowed by synovial joints ?
contracting muscles produces three common kinds of bone movements at synovial joints; gliding, angular movements (flexion, extension, abduction, adduction and circumduction and rotation
what are the types of synovial joints ?
plane (non-axial)
hinge or pivot (uniaxial)
condylar or saddle (biaxial)
ball and socket (multi-axial)
