Test #2 - Class 2: Skeletal System: Structure and Function Essentials; Class 3: Axial skeleton: Skull, Hyoid and Ossicles Flashcards
How many functions of bones are there?
5 functions
What are the 5 functions of bones?
- Support; 2. Protection; 3. Movement; 4. Storage; and 5. Blood Cell Formation
Bone Function: Support
Bone provides a framework for soft tissue (muscles, tendons and ligaments) to attach to.
Bone Function: Protection
The density of bone is protective of our internal organs.
Bone Function: Movement
Operating on a system of levers, when muscle shortens it pulls on bones to create movement at our joints.
Bone Function: Storage
Bone stores calcium and fat for the needs of the body.
Bone Function: Blood Cell Formation
Red blood cells, white blood cells, and platelets are formed in bone.
How many classifications for bone are there?
2 classifications
What are the 2 classifications for bone?
- By shape; and 2. By density.
How many bone densities are there?
2 densities
What are the 2 densities for bone?
- Compact; and 2. Spongy (Cancellous)
Bone Density: Compact
Dense bone with few if any holes in it.
What is compact bone good for?
It’s good for protection and support.
Bone Density: Spongy (Cancellous)
Bone with holes and spaces.
What is spongy bone good for?
It acts as a storage site for red bone marrow.
How many bone shapes are there?
6 shapes
What are the 6 bone shapes?
- Long Bones; 2. Short Bones; 3. Flat Bones; 4. Irregular Bones; 5. Sesamoid Bones; and 6. Wormian Bones
Bone Shape: Long Bones
Longer than they are wide.
Where are long bones in the body?
Mostly in the extremities (except carpals and tarsals).
Bone Shape: Short Bones
Shorter than they are wide.
Where are short bones in the body?
Carpals and tarsals.
Bone Shape: Flat Bones
Are flat in shape.
What are some examples of flat bones?
Scapula, ribs, skull and sternum.
Bone Shape: Irregular Bones
Are oddly shaped.
What are some examples of irregular bones?
Vertebrae and coxal.
Bone Shape: Sesamoid Bones
Small bones which are embedded in tendons to reduce friction and guide the movement of the tendon.
What is the largest sesamoid bone?
Patella (knee cap)
Bone Shape: Wormian Bones
Present in the fetal and newborn skull.
What is the function of wormian bone?
They act as a bridge between skull bones which have not completely fused.
Long Bone Structure: Diaphysis
The “shaft” of the bone.
It is made up of mostly compact bone. It has a hollow center. The nutrient foramen is a hole in any long bone. It serves as a pathway for blood vessels.
Long Bone Structure: Epiphysis
The “knobby” proximal and distal ends of a long bone.
The outside is made up of compact bone. The inside is made up of spongy bone.
Plural: epiphyses
Long Bone Structure: Epiphyseal Line
A tiny line between the diaphysis and epiphysis.
This is the location of bone growth in height through adolescence.
Long Bone Structure: Medullary Cavity
The hollow space within the diaphysis.
It acts as a storage site for yellow bone marrow.
Long Bone Structure: Yellow Bone Marrow
Is fatty connective tissue stored in the medullary cavity.
Serves as an alternative fuel source.
Long Bone Structure: Red Bone Marrow
Stored in spongy bone.
Immature blood cells in a gel-like consistency.
Long Bone Structure: Articular Cartilage
A glassy, smooth surface on the ends of long bones.
Made up of cartilage (hyaline). This reduces friction and allows for some shock absorbency.
Long Bone Structure: Periosteum
A dense connective tissue outer “skin” of a bone.
It covers the entire outside of the bone except where articular cartilage is located.
Loaded with nerve endings = sensitive!
How many functions of the periosteum are there?
3 functions
What are the 3 functions of the periosteum?
- Location of blood supply (provides nutrition) for the bone; 2. Location of growth in diameter; and 3. It serves as an attachment site for tendons and ligaments.
Long Bone Structure: Endosteum
The inner connective tissue lining of the medullary cavity.
Bone growth in diameter.
What is the wearing away of articular cartilage?
Osteoarthritis
What is the chemical composition of bone?
35% organic material (bone cells, proteins, blood vessels and nerves)
65% inorganic salts (calcium) and phosphorus
What gives bone its strength?
Calcium
What gives bone its flexibility?
Proteins
Bone markings are formed based on how many factors?
2 factors
What are the 2 factors that base the formation of bone markings?
- Calcium demands of the body: If we have too much calcium in our blood it can be stored in bone. If we have too little calcium in our blood we get more from bone.
- Mechanical stress: Wolf’s Law states that when mechanical stress is placed on bone, the bone thickens and gets stronger, this forms “bone markings”.
Bone Remodeling: Piezoelectric Property
When stress is placed on bone, a small electric current happens in the area. This causes bone cells called osteoblasts to become more active.
Bone Remodeling: Osteoblasts
Build bone by laying down calcium.
Bone Remodeling: Osteoclasts
Breakdown bone by releasing calcium.
The skeletal system is divided how many times?
2 divisions
What are the 2 divisions of the skeletal system?
- Axial Skeleton (head & torso); and
2. Appendicular Skeleton (upper and lower extremities)
What makes up the Axial Skeleton?
- Skull; 2. Vertebral column; 3. Rib cage; and 4. Sternum
How many bones make up the Axial Skeleton?
80 bones
How many bones in the skull?
22 bones
How many bones in the vertebral column?
26 bones
How many bones in the rib cage?
24 bones; or 12 pairs
How many bones in the sternum?
1 bone
How many bones in the Auditory Ossicles?
6 bones (3 in each ear/temporal bone)
How many bones in the Hyoid?
1 bone
What makes up the Appendicular Skeleton?
- Pectoral; 2. Upper extremity; 3. Pelvic; and 4. Lower extremity
How many bones make up the Appendicular Skeleton?
126 bones
How many bones in the pectoral?
4 bones
How many bones in the upper extremity?
60 bones; or 30 pairs
How many bones in the pelvic?
2 bones
How many bones in the lower extremity?
60 bones; or 30 pairs
How many bones in the human body?
206 bones
What is not included in the total number (206) of bones in the human body?
Sesamoid Bones (except the patella) and Wormian Bones
Bone Markings: Crest
Narrow ridge of bone, usually prominent (e.g. iliac crest)
The prefix “epi” means…
Upon or above
Bone Markings: Foramen
Round or oval opening through a bone (e.g. sciatic notch)
A foramen is like a donut hole.
Bone Markings: Meatus
A canal-like passageway (e.g. external auditory meatus; aka “ear canal”)
A meatus has length like a tunnel.
Bone Markings: Sinus
Cavity within a bone filled with air and lined with mucous membrane.
What parts of the axial skeleton are the skull divided into?
- Cranial; and 2. Facial
How many bones in the cranial division of the axial skeleton?
8 bones
How many bones in the facial division of the axial skeleton?
14 bones
List the 8 bones of the skull
- Frontal bone (1); 2. Parietal bones (2); 3. Occipital bone (1); 4. Temporal bones (2); 5. Sphenoid bone (1); and 6. Ethmoid bone (1)
Cranial Bones: Frontal
(1) - Forehead; forms the roof of the orbits (eye sockets) and forms the anterior cranial floor.
Cranial Bones: Parietal
(2) Form the superior, lateral, portion of the cranial cavity.
Cranial Bones: Occipital
Forms posterior portion and floor of cranial cavity.
How many bones markings on the occipital bone?
3 bone markings
What are the 3 bone markings on the occipital bone?
- Foramen magnum (spinal cord hole); 2. External Occipital Protuberance (EOP; bump on the back of the head); and 3. Superior Nuchal Line (extends laterally just above the EOP)
Cranial Bones: Temporal
(2) Forms the inferior, lateral portion of cranial cavity; Surrounds the ears.
How many bone markings on the temporal bones?
3 bone markings
What are the 3 bone markings on the temporal bones?
- Mandibular fossa (jaw sits in this depression and makes up 1/2 of the temporomandibular joint [TMJ]); 2. Mastoid Process (); and 3. External Auditory Meatus (“ear canal”; EAM)
Cranial Bones: Sphenoid
(1) “Keystone” of the cranial floor. Touches (articulates with) every other cranial bone (temple)
Resembles a bat with outstretched wings
Articulates with is synonymous with
Touches
Cranial Bones: Ethmoid
(1) Makes up the internal framework of the nasal cavity. It’s thin and porous (fragile).
How many bones markings on the ethmoid bone?
3 bone markings
What are the 3 bone markings on the ethmoid bone?
- Perpendicular plate (makes up 1/2 of the nasal septum); 2. Superior nasal conchae; and 3. Middle nasal conchae (they turbinate (swirl) air in nasal cavity so that it can be warmed, moistened and filtered.
How many sutures on the cranial bones of the axial skeleton?
4 sutures
What are the 4 sutures of the cranial bones of the axial skeleton?
- Sagittal (separates the 2 parietal bones); 2. Coronal (lies between the frontal and 2 parietal bones); 3. Squamous sutures (they lie between the temporal and parietal bone on each side of the skull); and 4. Lambdoid (lies between the occipital and 2 parietal bones).
What bones separate the sagittal suture?
Parietal bones
What bones lie between the coronal suture?
Frontal bone and 2 parietal bones
What bones lie between the squamous sutures?
Temporal bone and parietal bone
What bones lie between the lambdoid suture?
Occipital and 2 parietal bones
List the 14 bones of the face
- Mandible bone (1); 2. Maxillae bones (2); 3. Zygomatic bones (2); 4. Nasal bones (2); 5. Lacrimal bones (2); 6. Palatine bones (2); 7. Vomer bone (1); and 8. Inferior Nasal Conchae bones (2)
Facial Bones: Mandible
(1) Lower jaw bone; largest facial bone
Largest and strongest facial bone
How many bone markings on the mandible bone?
1 bone marking
What is the bone marking on the mandible bone?
- Mandibular condyle (makes up 1/2 of the temporomandibular joint [TMJ])
What makes up the temporomandibular joint?
Mandibular condyle (mandible) + Mandibular fossa (temporal) = temporomandibular joint (TMJ)
Facial Bones: Maxillae
(2) Houses upper row of teeth. They articulate with every other facial bone except the mandible. Forms floor of the eye sockets. Forms lateral walls of nasal cavity.
Singular = Maxilla
Facial Bones: Zygomatic
(2) Cheekbones; Also forms part of the floor of the eye sockets and lateral wall of the nasal cavity.
Facial Bones: Nasal
(2) Make up boney portion of the external nose.
Eyeglasses rest on this bone.
Facial Bones: Lacrimal
(2) House the tear ducts. Make up medial side of the eye socket. Tear ducts drain into nasal cavity.
Facial Bones: Palatine
(2) Make up the posterior portion of the hard palate.
Facial Bones: Vomer
(1) A plow-shaped bone making up the inferior portion of the nasal septum.
What makes up the hard palate?
Hard palate is made up of palatine and maxillae bones.
What makes up the nasal septum?
Nasal septum is made up of vomer bone and perpendicular plate (bone marking) of the ethmoid bone.
Facial Bones: Inferior Nasal Conchae
(2) Lateral projections in the nasal cavity to warm, moisten and filter air.
Functions similarly as the superior and middle nasal conchae (bone markings) of the ethmoid bone.
What are Paranasal Sinuses?
An open cavity within bone lined with mucous membranes.
The prefix “para” means…
Around
How many functions are there of the paranasal sinuses?
3 functions
What are the 3 functions of the paranasal sinuses?
- Lighten the weight of the skull; 2. Warm, moisten and filter air; and 3. Resonating chamber for speech
How many locations for the paranasal sinuses?
4 locations
What are the 4 locations of the paranasal sinuses?
- Frontal; 2. Ethmoid; 3. Sphenoid; and 4. Maxillary
Axial Skeleton Division: How many Auditory Ossicles are there?
3 in each ear (6 total)
Axial Skeleton Division: Where are the Auditory Ossicles located?
Temporal bones
Axial Skeleton Division: Hyoid
(1) A horseshoe-shaped bone suspended in the upper, anterior cervical region. Attached to the temporal bone by ligaments. It’s attached to the voice box.
Bone Markings: Tuberosity
Large, rounded projection; may be roughened
Bone Markings: Trochanter
Very large, blunt, irregularly shaped process (the only e.g. are on the femur)
Bone Markings: Line
Narrow ridge of bone; less prominent than a crest
What bone marking is less prominent than a crest?
A line
What bone marking is more prominent than a line?
A crest
Bone Markings: Tubercle
Small, rounded projection or process
What similar bone marking is larger than a tubercle?
A tuberosity
What similar bone marking is smaller than a tuberosity?
A tubercle
Bone Markings: Epicondyle
Raised area on or above a condyle
Bone Markings: Spine
Sharp, slender, often pointed projection (e.g. vertebra all have spinous processes down the vertebral column)
Bone Markings: Process
Any bony prominence
How many types of bone markings describe projections that are sites of muscle and ligament attachment?
8 bone markings
What are the 8 bone markings that describe projections that are sites of muscle and ligament attachments?
- Tuberosity; 2. Crest; 3. Trochanter; 4. Line; 5. Tubercle; 6. Epicondyle; 7. Spine; and 8. Process
Bone Markings: Head
Bony expansion carried on a narrow neck
Bone Markings: Facet
Smooth, nearly flat articular surface
Bone Markings: Condyle
Rounded articular projection
Bone Markings: Ramus
Armlike bar of bone
How many types of bone markings describe projections that help to form joints?
4 bone markings
What are the 4 bone markings that describe projections that help to form joints?
- Head; 2. Facet; 3. Condyle; and 4. Ramus
Bone Markings: Groove
Furrow (for passage of blood vessels and nerves)
Bone Markings: Fissure
Narrow, slitlike opening (for passage of blood vessels and nerves)
Bone Markings: Notch
Indentation at the edge of a structure (for passage of blood vessels and nerves)
Bone Markings: Fossa
Shallow, basinlike depression in a bone, often serving as an articular surface
How many types of bone markings describe depressions and openings?
7 bone markings
What are the 7 bone markings that describe depressions and openings?
- Groove; 2. Fissure; 3. Foramen; 4. Notch; 5. Meatus; 6. Sinus; and 7. Fossa
Bone Markings that begin with T are what category?
Projections or Processes
Bone Markings that begin with F are what category?
Depressions or Cavities (except Facet)
What are the only 2 paired bones of the skull?
- Parietal; and 2. Temporal
What are the only 2 singular facial bones?
- Mandible; and 2. Vomer
What are the 2 “keystone” bones of the skull?
- Sphenoid (cranial); and 2. Maxillae (facial)