Bones Flashcards
(28 cards)
What are the two types of bones? and their other names
Compact (cortical) and Spongey (Cancellous)
what do compact bones consist of? and what do spongey bones consist of?
compact - osteons
spongey - trabeculae
what are the things to remember about compact bones?
Compact (cortical)
- has osteons (structural unit)
- outer layer of bones
- in shaft or diaphysis of long bone
what are the things to remember about spongey bones?
Spongey bones (cancellous)
- has trabeculae
- inner layer of bones
- in ends or epiphysis of long bone
- contains red bone marrow
What is the membrane the lines the outer part of the bone? lines the diaphysis
Periosteum
- covers all part of bone except for the parts where joints are
- double layered
- Fibrous layer: Outer layer (dense CT)
- Osteogenic layer: Inner layer (contains osteoblasts)
What is the medullar cavity?
The hollow part of the bone that holds the bone marrow
what is the Endosteum?
the membrane that lines the medullar cavity
Types of bone marrow and their facts
Red bone marrow
- contains hematopoietic tissue (red colored tissue)
- mainly in flat bones
- production of blood cells (red, white,platelets)
Yellow bone marrow
- Contains fatty tissue (yellow colored tissue)
- in diaphysis of long bones
- fat storage / energy reserve
What are the 5 different types of bones?
Long, short, flat, sesamoid, and irregular
Examples of each of the 5 types of bones:
Long: limbs (legs, arms, fingers)
Short: wrist & ankles
Flat: rib cage and skull
Sesamoid: patella & pisiform
Irregular: skull, vertebrae, and hips
What are Osteons?
(Haversion system)
- structural units of compact bone
- those circular (cylindrical) things
What is the haversion canal? and what does it contain?
- Central hole in middle of Osteon
- Contains blood vessels and nerves
What is the lamellae?
layers of bone within compact bone
What are osteocytes and lacunae?
Osteocytes are mature bone cells that live inside lacunae
What are canals?
- Passageways for blood vessels
The different types of lamallae
Concentric - found in osteons, surrounds the central haversion canal
Interstitial - between osteons (incomplete layers)
Circumferential - outer and inner surfaces of bone. complete layers that go around the entire bone
Difference between central/haversion canal and Volkman’s canal?
Central canal runs vertically and Volkmans canal runs horizontally
What are canalculi
microscopic channels that connect lacunaes
What are fontanels?
soft spots on a baby’s skull
- dense CT membrane filled spaces
- over time the fontanels close
Different types of fontanels
Anterior Fontanel: top
Posterior Fontanel: top back
Sphenoidal (anterolateral) Fontanels: side front
Mastoid (posterolaterl) Fontanels: side back
when do the anterior and posterior fontanels close?
Anterior: between 12 months
Posterior: between 2-3 months
How many cranial bones are there? recall them
8 cranial bones
- Occipital
- parietal
- frontal
- temporal
- ethmoid
- sphenoid
How many facial bones are there? recall them
14 facial bones (2 with just one pair)
- nasal
- palatine
- lacrimal
- inferior nasal concha
- zygomatic
- maxilla
- mandible (only 1)
- vomer (only 1)
what are zygomatic bones?
Cheeckbones
