Skeleton (Ch. 7) Flashcards
What are the three main components of the axial skeleton? What are the two little extra parts?
- Skull
- Spine
- Thoracic cage
Extras: Hyoid bone and auditory ossicles
What do long bones look like, what do they do, and where are they found?
Length is greater than width - they are long
Diaphysis of compact bone
Epiphyses of spongy bone
Act as levers for body motion
Thigh, leg, arm, forearm, hands, feet, fingers, and toes
What do short bones look like, what do they do, and where are they found?
Nearly equal in length and width
Mainly made of spongy bone
Wrist and ankles
What do flat bones look like, what do they do, and where are they found?
Thin flat plates of spongy bone (may have thin compact bone lining)
Enclose and protect important organs
Provide large surface area for muscle attachment
Cranium, breastbone, ribs, shoulder blades
What do irregular bones look like, what do they do, and where are they found?
Don’t fit in other categories
Variable composition
Vertebrae, some facial bones
What do sesamoid bones look like, what do they do, and where are they found?
Look like sesame seeds
Develop in tendons
Provide strength and stability to areas of unusual mechanical stress
Patellas
What are sutural bones? Where are they found? Does everyone have them?
Small bones that may occur within sutures between cranial bones
Only some people have them
What is a tuberosity?
Large rounded projection
May be roughened
What is a crest?
Narrow ridge of bone, usually prominent
What is a trochanter?
Femur only
Very large, blunt, irregularly-shaped process
What is a line (bone marking)?
Narrow ridge of bone - less prominent than a crest
What is a tubercle?
Small rounded projection or process
What is an epicondyle?
Raised area on or above a condyle
What is a spine (bone marking)?
Sharp, slender, often pointed projection (spinous process of vertebrae, ischial spine)
What is a process (bone marking)?
Any bony prominence
What part of the bone is the facet?
Smooth, nearly flat articular surface
Ribs attach to spinal cartilage via facets
What is a condyle on a bone?
Rounded articular projection
Mandible has a condyle at the superior posterior position where it attaches to the maxilla
Femur has condyles
What is a ramus on a bone?
Armlike bar of a bone
The rising part of the mandible is the ramus
What is a groove in a bone?
Furrow (for blood passage)
What is a fissure (in a healthy bone)?
Narrow, slit-like opening
Crack
Inferior orbital fissures
For blood passage
What is a foramen?
Round or oval opening through a bone
Hole
What is a notch (in a healthy bone)?
An indentation at the edge
What is a meatus?
Tunnel
Canal-like passageway
Auditory meatus
What is a sinus?
Bone cavity
Filled with air
Lined with mucous membrane
What is a fossa?
Pocket or cup
Shallow basin-like depression in a bone
Often an articular surface
What is a sulcus?
Groove in a bone
What do bone processes attach to to protect muscles from tension (pulling) forces?
Tendons and ligaments
What do condyles, facets, and heads of bones have in common?
They are joint surfaces
What do lines, crests, spinous processes, tubercles, tuberosities, trochanters, and epicondyles have in common?
They are sites of attachment
What do the head, ribs, pelvic girdle, and back muscles all attach to?
The vertebral column
How many cervical vertebrae are there?
7
How many thoracic vertebrae are there?
12
How many lumbar vertebrae are there?
5
How many vertebrae are there fused together in the sacrum?
5
How many vertebrae are there fused in the coccyx?
4
What is the primary curve of the spine, as opposed to the secondary curves?
Primary - Fetal (thoracic and sacral)
Secondary - As baby starts to lift head, stand (cervical and lumbar)
What are the three abnormal spinal curves?
- Kyphosis (humpback)
- Lordosis (booty out)
- Scoliosis (lateral curvature)
What are the three abnormal spinal curves?
- Kyphosis (humpback)
- Lordosis (booty out/”swayback”)
- Scoliosis (lateral curvature)
What are the 3 main parts of a typical vertebra?
- Vertebral body (thick part)
- Vertebral arch (surrounds spinal cord)
- Vertebral processes (sites of articulation/facets)
Which vertebrae have intervertebral discs between them?
C2-sacrum
When you nod your head, what does the atlas vertebra articulate with on the skull?
The occipital condyles
What part of the axis vertebra makes a pivot joint with the atlas (and makes us able to shake our heads “no”)?
The dens of the axis (tooth)
Which kind of vertebrae have the smallest bodies? Medium? Largest?
Smallest: Cervical
Medium: Thoracic
Largest: Lumbar
Which type of vertebrae articulate with the ribs?
Thoracic vertebrae
Which type of vertebrae look like giraffes, and which look like moose?
Giraffes = thoracic Moose = lumbar
Which type of vertebrae has superior and inferior articular facets, and which type has medial and lateral articular facets?
Superior and inferior: cervical and thoracic (giraffe)
Superior - cervical (s sounds)
Medial and lateral: Moose: Lumbar
Medial - moose (m sounds)
On the sacrum, what is the median sacral crest formed from?
Fused spinous processes of the sacral vertebrae
On the sacrum, what is the sacral canal formed from?
Fused vertebral foramina of the sacral vertebrae
What is the sacral hiatus?
Inferior entrance to vertebral canal
Where epidurals are injected into
What is the inferior entrance to the vertebral canal called (where epidural injections are given)?
Sacral hiatus
What is the coccygeal cornua? Which sex has one that points inferiorly, and which points anteriorly?
Dorsal process at the apex of the sacrum
Females - Inferiorly
Males - Anteriorly
What are the three parts of the sternum?
- Manubrium (superior)
- Body
- Xiphoid process (inferior)
How many ribs do people normally have? How many are true ribs and how many are false ribs?
12 pairs altogether
True ribs - 7 pairs
False ribs - 5 (3 attached to other costal cartilages, 2 floating ribs w/ no anterior attachment)
Does the head of the rib articulate with the vertebral body or the costal cartilage?
Head of rib connects to vertebral body
The head and the body connect.
What are the 4 major cranial sutures?
- Coronal (frontal-parietal)
- Sagittal (L-R parietals)
- Lamboidal (occipital-pareital)
- Squamous (parietal-temple)
What 4 bones work together to form the paranasal sinuses?
- Frontal
- Sphenoid
- Ethmoid
- Maxillary
What 2 bones form the nasal septum? What connects them?
- Vomer
- Ethmoid
Connected by septal cartilage
What are 2 functions of the sinuses?
Produce mucus, which moisturizes and warms inhaled air
Resonating chambers for speech
Which cranial bone looks like a bat, and which looks like a walnut?
Bat = Sphenoid Walnut = Ethmoid
Are the sphenoid and ethmoid bones cranial bones or facial bones?
Cranial
What are the 8 bones of the cranium (8 includes L and R)?
Frontal L/R Parietal L/R Temporal Occipital Sphenoid Ethmoid
What two bones together make up the pectoral girdle?
The clavicle and the scapula
