Skeletal System Flashcards
List the 5 general functions of bones
- Support
- Protect Internal Organs (axial)
- Facilitate Movement (appendicular)
- Make blood cells
- Release & Store minerals and fats
List the 5 classes of bones
- Long - longer than they are wide, facilitate movement
- Short - cube-like, provide stability and support
- Flat - thin plates that protect internal organs
- Irregular - Varied shapes, protect internal organs
- Sesamoid - have varied shapes and protect tendons
List the 4 structural components of an osteon
- Central canal - carries nerves and blood vertically
- Concentric lamellae - circular rings of bone around the central canal
- Lacunae (look like bugs) - spaces for osteocytes
- Canaliculi (the bug’s legs) - link lacunae together
What are the gross anatomy features of long bones?
- Diaphysis (central portion) acts as lever for body movement
- Medullary Cavity (hollow interior) contains yellow marrow
- Epiphysis/Epiphyses (end regions) contains spongy bone and red marrow
- Epiphysial line - ossified remnant of epiphyseal plate
Periosteum
Fibrous outer membrane that covers tendons and ligaments
Endosteum
Delicate membrane lining the medullary cavity
Articular Cartilage
A layer of hyaline cartilage reducing friction and absorbing shocks (at points of articulation)
Why do bones need osteons?
Osteons provide blood, which keeps bones alive.
Why doesn’t all compact bone have osteons?
Thinner compact bones can get nutrients from periosteum and endosteum instead
What two aspects of bone structure can be studied to understand bone function?
Structure and ______
What features of bird bones allow them to fly?
Slender, elongated, thin bones with thin cortical walls
What are the 2 major components of bone extracellular matrix and what do they do?
collagen for flexiblity and calcium ions to resist compression
What are the two kinds of bone marrow?
Red, forms blood cells and the precursor to the immune system
Yellow, stores fat cells
What is the difference between cortical bone and cancellous bone?
Cortical is hard, calcaneous is cancellous
List the three major bone cells and their functions
- Osteogenic Cells are stem cells that develop osteoblasts
- Osteoblasts are reaponsible for forming new bine matrix by releasing calcium and collagen
- Osteocytes get trapped inside the lacunae in the bone to maintain the extracellular matrix
Osteoclasts
Absorb old bone matrix by creating an absorption pit
Bone Remodeling
Removes old bone and deposits new bone to repair injuries or adapt to disuses
What are the two main forms of bone development?
Intramembranous ossification is the process by which bone develops withon sheets of connective tossue
Endochondral Ossification is the process in which bone replaces hyaline cartilage (most bones, esp. long bones created this way)
What are the 8 steps of endochondral ossification?
- Model Embryonic cells develop into chondrocytes and construct a hyaline cartilage model
- Middle Out The matrix in diaphysis region begins to calcify
- Fill ‘er Up blood vessels penetrate the calcified cartilage and carry osteogenic cells into the model
- Cap the Ends materix in epiphysis region begins to calcify
- Fill the Ends same as 3
- Plates **the ephiphylial plate is created between the ephysis and diaphysis
- Grow cartilage growth at epiphyseal plate allows bones to lengthen
- End of the Line Epiphysial line forma when cartilage is completely replaced by bone
List the 5 Zones of the epiphyseal plate
- Zone of reserve - secures cartilage to ephysis
- Zone of proliferation - cells divide and organize into columns like pros
- Zone of maturation - aka hypertrophy, where cells grow and divide
- Zone of calcification - chondorcytes die and cartilage calcifies
- Zone of ossification - cartilage is replaced by bone
What are the two regions of the skeleton?
Axial the head and trunk
Appendicular the limbs
What is the name for the collection of bones that protect the brain, middle, and inner ear structures?
Cranial
What is the name for the collection of bones that form the face, nasal cavity, orbits, and teeth?
Facial
How does the size of a muscle influence the attachment sight of a bone?
The bigger the bigger
Styloid Process
Landmark on the temporal bone;
A slender projection for tongue and larynx
Mastoid Process
Temporal Bone landmark; a large projection for the attachment of neck muscles
External acoustic meatus
Temporal bone landmark;
A passage for sound to reach the middle ear
Zygomatic Arch
Temporal bone landmark;
A horizontal bar connecting to the zygomatic bone : attachment site for chewing
Olfactory Foramen
Ethnoid landmark; coral-looking hole dor olfactory nerves to move into the nasal passage
Crista Galli
Ethnoid landmark; ridge-like projection for attachment of membranes that cover the brain
Sella turcica
Sphenoid landmark; a saddle-shaped depression that houses the pituitary gland
Foramen Rotundum
Sphenoid landmark; round hole for branch of trigemin nerves connecting to maxillary branch
Foramen Ovale
Sphenoid landmark; posterior relative to f. rotundum, hole for the mandibular branch of the trigeminal nerve
Internal Acoustic Meatus
Temporal landmark; passage for vestibulo-cochlear and facial nerves
Hypoglossal canal
Occipital landmark; small holes on sides of spinal column
Vulmar
Small bine in sphenoid behind maxillary
Mandibular fossa
Temporal landmark; depression that allows for articulation of the mandible
Carotid canal
Temporal landmark; passage for internal carotid artery to supply blood to the brain
Jugular Foramen
Temporal landmark; near occipital bone, passage for jugular vein , vagus, and accessory nerves
Occipital Condyle
Occipital landmark; oval-shaped knob that allows articulation with the C1 vertebrae
Foramen Magnum
Occipital landmark; Large hole for spinal cord and vertebral arteries
External occipital protuberance
Occipital landmark; Raised area for connection of trapezius muscle
Superior Orbital Fissure
Sphenoid landmark; a gap visible through the orbit (eyehole) for nerves involved in eye movement
Optic Canal
Sphenoid Landmark; passage for the optic nerve. Small hole medial relative to the superior orbital fissure
Inferior Orbital Fissure
Sphenoid landmark; lower gap vosible through orbit that allows passage of zygomatic nerve
Nasal Conchae
Ethnoid landmark; Three curved projections that increase nasal surface
Condyloid Process
Mandibular landmark; knob-like projection that articulates with temporal zone (posterior most superior part of mandible)
Coronoid Process
Mandibular landmark; Knob-like projection for chewing muscles to attach: anterior relative to the condyloid process
Mandibular Foramen
Mandibular landmark; opening for mandibular branch of trigeminal nerve (posterior hole)
Mental Foramen
Mandibular landmark; anterior hole, opening for nerve sensation to the chin
What structures need to be able to move in to and out of the skull?
Nerves, arteries, and veins
What are the 4 paranasal sinuses (in what bones are they found?)
- Frontal sinus
- Ethnoidal sinus
- Maxillary Sinus
- Sphenoidal sinus
What are the 4 sutures?
- Coronal suture connects frontal and parietal bones
-
Sagital suture connects parietal bones to one another
3 Lamboid suture connects occipita to parietals - Squamous suture connects temporarl bones to parietal bones
What is the functional importance of fontanelles?
To accommodate brain growth and squeezing through the birth canal
Why do sperm whales have a higher mineral content in their ear bones?
They are put under greater forces, like pressure
What are the 6 auditory ossicles?
The left malleus, incus, and stapes & the right Malleus, Incus, and Stapes
Hyoid
A u-shaped bone in the neck that serves as the base for tongue muscles
What are the five regions of the vertebral column from superior to inferior?
Cervical
Thoracic
Lumbar
Sacrum
Cocyx
Supraspinous Process
Vertebra; a posterior projection for muscle attachment
Transverse processes
Vertebra; latera projections
Vertebral foramen
Vertebra, the hole that aloes the spinal column
What is the cancellous bone anterior part of a vertebra called?
The body
Superior Articular Process
Vertebra; connects with inferior process on vertebra above it to form a joint
Inferior articular process
Vertebra, the space between vertebrae
Intervertebral foramen
Opening between adjacent vertebrae for the spinal nerve
Intrevertebral discs
Fibrocartilage pads that provide cushioning and enable movement of vertebrae
What vertebrae can one expect to have the largest bodies?
Lumbar, because they have to withstand more force
How does osteoporosis negatively affect bone health?
Vertebral bodies collapse as vertebrae deteriorate
Our ribs are associated with which vertebrae?
Thoracic
Landmarks of the sternum
- Manubrium; broad superior-most part
- Body; long middle section
- Xyphoid process; inferior most region
Suprastenal notch
Depression on superiormost part of the manubrium
Sternal angle
The boundary between the manubrium and body if the sternum
Costal Cartilage
Hyaline cartilage connecting ribs to sternum; increases flexibility of thorax
What are the varieties of rib?
- True ribs; connected to the sternum
- False ribs; inferior to true, no direct connection
- Floating ribs; false ribs that do not connect at all
