skeleton system Flashcards
Define osteoblasts
bone-forming cells
Define osteoclasts
large cells break down bone matrix
Define osteocytes
mature bone cell
Define osteon
structural/function of compact bone
What are the 5 functions of bones?
- support
- protection
- movement
- storing minerals/fats
- producing blood cells
anatomical difference between spongy and compact bone?
Compact: dense, smooth, homogeneous, osteons
Spongy: needlelike bone, open spaces, no central canal, trabeculea
How many bones does the adult skeleton have?
206
2 types of bone tissue?
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- compact
- spongy
4 groups bone is classified under?
- long
- short
- flat
- irregular
2 special categories bones are classified under?
- wormian
- sesamoid
5 anatomical features of a long bone.
- diaphysis
- periosteum
- epiphysis
- articular cartilage
- Epiphyseal line/plate
2 anatomical features of a short bone
- cube-shaped
- spongy, compact outer layer
sesamoid bone is what type of bone?
short bone
sesamoid bones form where?
within tendons or muscles
2 anatomical features of a flat bones?
- thin,flat,curved
- spongy bone between two layer compact bone
2 examples of long bones
- femur
- humerus
2 examples of short bones
- carpals
- tarsals
3 examples of flat bones
- most of skull
- ribs
- sternum
2 anatomical features of an irregular bone
- irregular shape
- do not fit in other categories
2 examples of irregular bones
- vertebrae
- facial bones
example of a sesamoid bone
patella
anatomical feature of a wormian bone
form in the sutures of the skull plates
example of wormian bone
only found between the skull plates
2 divisions of skeletal system
- axial
- appendicular
diaphysis is what & what is it composed of?
- shaft
- compact bone
periosteum is what & what 1 tissue/fiber each?
- covering of diaphysis
- dense irregular
- sharpy fibers
What is the covering surrounding the shaft?
periosteum
What is stored in the medullary cavity?
yellow bone marrow
where does red blood production occur?
red bone marrow in the epiphysis
How do you know if a bone still growing?
if there is an epiphyseal plate present
3 types of bone cells?
- Osteoblast
- Osteocyte
- Osteogenic cell
2 functions of the osteoblast?
- lines outside of bone
- forms bone matrix
Function of osteoclast
breaks down matrix
Function of osteocyte
maintains bone matrix
Describe the microscopic structure of compact bone
- osteons(haversian system)
- Central (Haversian) canal
- Canaliculi
- Perforating(molkmann’s) canal
What is the lamellae?
- extracellular(bone) matrix
- rings around the central canal
3 structures found in the central canal
- arteries
- veins
- nerves
what is the name of the cytoplasmic extension that allows osteocytes to communicate with the central canal?
canaliculi
where do you find compact bone?
outer layer of the bone
where do you find spongy bones?
inner layer of the bone
what are the 4 functions of compact bone?
- support
- movement
- protection
- strength
what is the function of spongy bone?
- providing support
- flexibility
3 bone processes
- bone formation
- bone remodeling
- bone repair
6 type of connective tissue that bones are composed of
- loose connective tissue
- adipose tissue
- dense fibrous connective tissue
- elastic connective tissue
- cartilage
- bone tissue,
- blood tissue
what are the 4 steps of intramembranous ossification?
- development of ossification center
- calcification
- formating of trabeculae
- development of periosteum
ossification is what processes?
bone formation
renewal is what processes?
bone remodeling
What bones of the skeleton are formed by intramembranous ossification?
- skull
- maxilla
- mandible
- clavicle
What are the 6 steps of endochondral ossification?
- development of cartilage model
- growth of cartilage model
- development of primary ossification center
- development of medullary cavity
- development of second ossification center
- formation of articular cartilage/epiphyseal plate
2 phases in ossification in long bones
- osteoblast cover hyaline cartilage with bone matrix
- enclosed cartilage in fetus is digested away making medullary cavity
what are the 5 difference between intramembranous ossification and endochondral ossification?
- differ in number of steps
- ossify different bones
- endochondral starts with a cartilaginous model
- 2 ossification centers in endochondral, 1 in intramembranous
- both occur during fetal development but endochondral continues post-nataly
What bones of the skeleton are formed by endochondral ossification?
rest of the bones
What is bone remodeling?
process of repairing or maintaining bone by adding or removing bone matrix
why is bone remodeling important?
retain normal proportions and strength during long-bone growth
What are the 4 stages of bone repair?
- hematoma forms
- fibrocartilage callus forms
- bony callus forms
- bone remodeling occurs
If blood calcium level is high, what lowers the blood calcium?
thyroid gland releasing calcitonin
If blood calcium levels are low, what raises the blood calcium?
parathyroid gland releases parathyroid hormone
How does calcitonin and PTH play a role in regulating proper blood calcium levels
calcitonin stimulates osteoblasts that will grow bone
PTH will stimulate osteoclast that will break down bone
What are the stages of bone repair?
- hematoma
- fibrocartilaginous callus
- bony callus
- bone remodeling
what are the 8 bone fractures?
- greenstick
- spiral
- comminuted
- compression
- depression
- oblique
- epiphyseal
- transverse
2 characteristics of a greenstick fracture?
- common in children
- bend or crack in an incomplete break
2 characteristics in an oblique fracture?
- common in sports
- twisting force
what is a comminuted fracture?
bone broken into many pieces
2 characteristics of a compression fracture?
- common in elderly
- bones are crushed
what is a depression fracture?
bone moves inward
what is an oblique fracture?
happens diagnal to the long axis
what is an epiphyseal fracture?
breaks along the epiphysis
what is a transverse fracture?
breaks perpendicular to the long axis
List the types of vertebra
- cervical
- thoracic
- lumbar
- sacral
- coccyx
how many bones does the cervical have?
7
how many bones does the thoracic have?
12
how many bones does the lumbar have?
5
how many does the sacral have?
5 fused
Identify the 3 parts of the rib cage.
- True
- false
- floating
What are the 4 spinal curvatures?
- normal
- scoliosis
- kyphosis
- lordosis
List all 6 bones of the axial skeleton
- skull
- facial bones
- vertebra
- sacrum
- sternum
- ribs
what are the 6 bones of the cranium?
- frontal
- parietal
- temporal
- occipital
- sphenoid
- ethmoid
3 parts of the skull does the frontal bone form?
- forehead
- bony projections under the eyebrows
- superior part of each eye’s orbit
what part of the skull does the parietal bone form?
superior and lateral walls of the cranium
what part of the skull does the temporal bone form?
inferior to the parietal bones and join them at the squamous sutures
what part of the skull does the occipital bone form?
the base and back wall of the skull
what part of the skull does the sphenoid bone form?
spans the width of the skull and forms part of the floor of the cranial cavity
what part of the skull does the ethmoid bone form?
the roof of the nasal cavity and part of the medial walls of the orbits
what 6 features does the vertebra have?
- Body(centrum)
- arch
- foramen
- Transverse processes
- Spinous process
- Superior/inferior articular process
What 2 bones do the ribs articulate with?
sternum
vertebral column
How many true ribs?
7 pairs
how many false ribs?
5 pair
how many floating ribs?
2 pair
what kind of cartilage are the ribs connected by?
costal cartilages
What direction does each lie in relation to the posterior aspect of the body?
All the ribs articulate with the vertebral column posteriorly and then curve downward and toward the anterior body surface
what are the 8 bones of the shoulder girdle?
- clavicle
- scapula
- humerus
- radius
- ulna
- carpals
- metacarpals
- phalanges
what are the 9 bones of the pelvic girdle?
- coxal
- sacrum
- coccyx
- femur
- fibula
- tibia
- tarsals
- metatarsals
- phalanges
What are the 6 differences between the female and male pelvic girdles?
- The female inlet is larger and more circular.
- pelvis is shallower
- bones are lighter and thinner.
- ilia flare more laterally
- sacrum is shorter and less curved.
- ischial spines are shorter and farther apart
- pubic arch is more rounded
