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187 Cards in this Set
- Front
- Back
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What are the two types of human skeleton?
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Axial & Appendicular
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What type of human skeleton is the skull?
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Axial
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How many bones is the skull composed of?
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22 - 8 Cranial and 14 Facial
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What does the skull articulate with?
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Atlas (C1)
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Encases and protects the brain in the cranial cavity
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The Skull or Cranium
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What are the 8 cranial bones?
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Frontal, Parietal, Temporal, Occipital, Sphenoid, and Ethmoid
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Forms the anterior aspect of the cranial vault - the forehead - forms the superior aspect of the orbit for eyes
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Frontal Bone
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Bony ridge underneath eyebrows
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Supraorbital margin
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Passageway for supraorbital nerve and artery
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Supraorbital Foramen
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Houses and supports frontal lobes of the brain
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Anterior Cranial Fossa
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Matched pair on either side of the head - form the sides of the vault
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Parietal Bone
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Articulation between the frontal bone and the two parietal bones of the skull
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Coronal Suture
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Central articulation between two parietal bones
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Sagittal Suture
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Forms posterior part of cranial vault - Also forms much of the base of the cranium - forms floor of the posterior cranial fossa
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Occipital Bone
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Medulla Oblongata connects with the spinal cord - Vertebral and spinal arteries also pass through this opening
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Foramen Magnum
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Prominent midline bump - attachment point for ligamentum nuchae to C7 attachment point
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External Occipital Protuberance
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Convex, oval processes; articulation with atlas
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Occipital Condyles
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Articulation between parietal bones and occipital bones
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Lamboidal Suture
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Matched pair on either side of skull - Inferior to parietals - form inferior aspects of cranium
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Temporal Bone
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Flat area just inferior to parietal bone
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Squamous Region
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Articulates with zygomatic bone to form zygomatic arch
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Zygomatic Process
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Forms articulating surface of the temporomandibular joint
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Mandibular Fossa
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Ear Canal; directs sound waves into inner ear
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External auditory meatus
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Projects inferiorly from interior surface of temporal bone - Point of attachment for muscles and ligaments of tongue and neck
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Styloid process
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Posterior and inferior to external meatus - attachment site for several neck muscles
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Mastoid Process
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Accommodates cranial nerves VII and VIII
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Internal auditory meatus
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Forms floor of the medial cranial fossa
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Petrous Region
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Articulation between the parietal bones and temporal bones
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Squamous suture
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Articulation between temporal bones and occipital bone
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Occipitomastoid Suture
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Wing-shape or butterfly shape that spans floor of middle cranial fossa - Articulates with other 7 cranial bones
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Sphenoid Bone
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Extend laterally - contribute to posterior orbit - articulate with frontal, parietal, and temporal bones
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Greater Wings of Sphenoid Bone
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A ridge of bone anterior and superior to greater wings - forms part of floor of cranium and part of orbit
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Lesser Wings of Sphenoid bone
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Saddle shaped region in central superior region of sphenoid bone
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Sella Turcica
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Extend inferiorly - form lateral, posterior region of nasal cavity
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Pterygoid Process
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Space between greater and and lesser wings - Passageway for 3 cranial nerves
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Superior Orbital Fissue
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Light, sponge-like bone - Sits posterior of nasal bone, anterior of sphenoid bone - Forms thin medial wall of orbit
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Ethmoid Bone
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Superior ridge that separates two halves of anterior cranial fossa
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Crista Galli
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Roof of nasal cavity - contains olfactory foramina for passage of olfactory nerve fibers from nasal cavity to brain
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Cribiform plate
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Form bridge of nose - fused along center line - remainder of nose is cartilage - articulate laterally with maxillae
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Nasal Bones
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Resemble fingernail in size and shape - smallest bones of face - form part of medial wall of each orbit
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Lacrimal Bones
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L-shaped bones anterior to sphenoid - helps form posterior portion of hard palate, posterior portion of floor and walls of nasal cavity, and a very small portion of floor of orbits
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Palatine Bones
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Small wedge-shaped bone located within nasal cavity - helps form inferior part of nasal septum
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Vomer Bone
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Thin bones that project into nasal cavity from lateral walls of nasal cavity - Increase mucosal covered surface area of nasal cavity and help swirl air and filter air as it passes through nasal cavity
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Inferior Nasal Conchae
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Fused together to form central region of face and upper jaw - form part of the floor of the orbits, lateral walls and floor of nasal cavity, and most of hard palate
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Maxillary Bones
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Separates nasal cavity from oral cavity
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Hard Palate
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Just below orbit - passageway for infraorbital nerve and artery
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Infraorbital Foramen
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"Cheek bones" - articulates with zygomatic process of temporal bone - also articulates with frontal, maxillary, and sphenoid bones - part of lateral wall and floor of each orbit
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Zygomatic Bones
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"Lower jaw bone" - largest and strongest bone of face - mental protuberance - mental foramen
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Mandible
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Passageway for mental nerve
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Mental Foramen
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Posteriorly projecting sides of the mandible
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Body of Mandible
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Superiorly directed extensions of mandible toward the TMJ
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Ramus of Mandible
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Where the body and ramus meet
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Mandibular angle
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Superior anterior project of ramus - insertion for temporalis muscle
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Coronoid Process
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Half of TMJ, round, convex surface that articulates with mandibular fossa of temporal bone
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Mandibular Condyles
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Free floating bone - suspended from styloid process of temporal bones via ligaments and muscle - positioned just above larynx - Supports tongue
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Hyoid Bone
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- Anterior aspect of epicranius
- Origin: Epicranial aponeuosis - Insertion: skin superior to supraorbital - Action: Raises eyebrows, wrinkles, skin of forehead - Innervation: Facial nerve |
Occipitofrontalis
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- Posterior aspect of epicranius
- Origin: Occipital Bone - Insertion: Epicranial aponeurosis - Action: Pulls scalp posteriorly - Innervation: Facial nerve |
Occipitalis Epicranius
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- Major muscle of chewing
- Origin: Zygomatic arch - Insertion: Angle and ramus of mandible - Action: Elevates mandible, closes jaw - Innervation: Trigeminal Nerve |
Masseter
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- Fan shaped muscle, passes under zygomatic arch
- Origin: broad attachment on temporal bone - Insertion: Coronoid process and ramus of mandible - Action: Closes jaw, elevates and retracts mandible - Innervation: Trigeminal Nerve |
Temporalis
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- Deep to masseter and zygomatic arch
- Origin: Maxilla, sphenoid bones - Insertion: Inside edge of mandible near angle - Action: Closes jaw, grinding, side to side jaw motion - Innervation: Trigeminal Nerve |
Medial Pterygoid
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- Deep to masseter, superior to medial pterygoid
- Origin: Sphenoid - Insertion: Condyle of mandible, TMJ capsule - Action: Pulls mandible anteriorly, chewing, grinding - Innervation: Trigeminal nerve |
Lateral Pterygoid
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- Deep cheek muscle under masseter, quadrilateral shape
- Origin: Lateral Maxilla and mandible - Insertion: Orbicularis oris fibers near corner of mouth - Action: Flattens cheek area, holds food in place for chewing, sucking - Innervation: Facial Nerve |
Buccinator
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- Flat, fan-shaped muscle
- Origin: Interior aspect of anterior mandible - Insertion: Inferior tongue and hyoid - Action: Depresses tongue, thrusts tongue forward - Innervation: Hypoglossal nerve |
Genioglossus
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- Flat muscle
- Origin: Greater horn and body of hyoid bone - Insertion: Side of tounge - Action: Depresses tongue, draws down sides of tongue, pulls tongue backward - Innervation: Hypoglossal nerve |
Hypoglossus
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- Oriented perpendicular to hypoglossus
- Origin: Styloid process of temporal bone - Insertion: Sides and undersurface of tongue - Action: Retracts and elevates the tongue - Innervation: Hypoglossal nerve |
Styloglossus
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- Small strap-like muscle
- Origin: Common annular tendon - Insertion: Lateral eyeball - Action: Rotates eye laterally - Innervation: Abducens nerve |
Lateral Rectus
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- Small strap-like muscle
- Origin: Common annular tendon - Insertion: Medial eyeball - Action: Rotates eye medially - Innervation: Occulomotor nerve |
Medial Rectus
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- Small strap-like muscle
- Origin: Common annular tendon - Insertion: Superior eyeball - Action: Rotates eye superiorly - Innervation: Occulomotor Nerve |
Superior Rectus
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- Small strap-like muscle
- Origin: Common Annular tendon - Insertion: Inferior eyeball - Action: Rotates eye inferiorly - Innervation: Occulomotor Nerve |
Inferior Rectus
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- Passes through trochlear pulley anterior and medial of insertion
- Origin: Common annular tendon - Insertion: Superior eyeball - Action: Rotates eye downward laterally - Innervation: Trochlear Nerve |
Superior Oblique
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- Runs laterally under eyeball
- Origin: Medial Orbit - Insertion: lateral, inferior eyeball - Action: Rotates eye upward and laterally - Innervation: Occulomotor Nerve |
Inferior Oblique
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Encases spinal cord - protects spinal cord and spinal nerve roots from damage - elaborate system of trunk muscles acts on the levels of the vertebral bodies to fine-tune trunk position
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Vertebral Column
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How many cervical vertebrae are there?
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7
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How many thoracic vertebrae are there?
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12
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How many lumbar vertebrae are there?
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5
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How many sacral vertebrae are there?
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5 fused sacral vertebrae
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How many coccyx vertebrae are there?
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4 Fused
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Curvature of the thoracic region - concavity anteriorly
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Kyphosis
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Cervical and lumbar regions - concavity is oriented posteriorly
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Lordosis
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Lateral bending, usually in thoracic region
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Scoliosis
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Articulation between superior articular facets of inferior vertebrae with inferior articular facets of superior verterae
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Zygaphyseal Joint
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Atlas articular surfaces are concave to receive occipital condyles - allows flexion and extension
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Atlanto-occipital
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Pivot joint; shaking head "no"
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Atlanto-axial
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Triangular bone formed by fusion of 5 sacral vertebrae - fusing begins around 16-18 and ends by age 30 - Base: articulation with coccyx - apex: articulation with coccyx
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Sacrum
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Fibrous ring consisting of fibrocartilage
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Annulus fibrosus
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soft, pulpy, highly elastic substance forming inner core of disc
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Nucleus pulposus
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Sit between bodies of adjacent vertebrae; permit some movement, absorb vertical shock
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Discs
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Composed of cell bodies and some unmyelinated fibers
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Gray Matter
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Lies within brain - composed of myelinated fibers
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White Matter
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Darker colored concentrations of cell bodies deep within the brain
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Nuclei
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Connective tissue membranes that cover & protect
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Cranial Meninges
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Tough double outer layer of connective tissue - can be separated by sinuses that collect and drain venous blood
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Dura Mater
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Looser covering - maintains the subarachnoid space - contains cerebrospinal fluid
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Arachnoid Membrane
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Nourish the brain delicate membrane rich blood supply in tight apposition to nervous tissue
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Pia Mater
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Large, folded - superiorly oriented - cover other more internal structures
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Cerebral Hemispheres
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Central region includes thalamus and hypothalamus
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Diencephalon
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Includes midbrain, pons, and medulla oblongata
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Brain Stem
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Inferior and posterior to the cerebral hemispheres
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Cerebellum
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Cavities within the brain filled with cerebrospinal fluid
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Ventricles
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C-Shaped within the cerebral hemispheres - composed of an anterior, posterior, and inferior horns
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Lateral Ventricles
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Located within the diencephalon - connected to lateral ventricles by the intraventricular foramen
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Third Ventricle
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Lies anterior to cerebellum at base of brain - communicates to 3rd ventricle via the cerebral aquaduct - communicates to subarachnoid space via the medial and lateral apertures
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Fourth Ventricle
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Ridges
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Gyri
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Shallow Grooves
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Sulci
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Deeper grooves
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Fissures
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Separates hemispheres
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Medial Longitudinal Fissure
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Separates cerebral hemispheres from cerebellum
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Transverse Fissure
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Separates the frontal lobe from the parietal lobe
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Central Sulcus
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Separates the occipital lobe from the parietal lobe
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Parieto-occipital
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Separates the temporal lobe from the frontal and parietal lobes
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Lateral Sulcus
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Center of thought and emotion
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Pre-Frontal Cortex
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In the precentral gyrus - initiates voluntary movements - regional mapping of motor function
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Primary Motor Cortex
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Processing of skilled coordinated motion - programming of learned and practiced motor skills
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Pre-Motor Cortex
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Speech Center - Only in left hemisphere
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Broca's Area
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In the post-central gyrus - sensory processing
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Primary Sensory Cortex
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Communication between the two cerebral hemispheres - myelinated fibers connecting the cerebral hemispheres - responsible for inter hemispheric communication - largest mass of networking fibers in the brain
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Corpus Callosum
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80% of the diencephalon - pair of egg shaped masses of gray matter - major relay station for most sensory impulses that reach primary sensory cortex
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Thalamus
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A small part of the diencephalon located inferior to thalamus - sensory input related to somatic and visceral senses, vision, taste, and smell directed through hypothalamus - plays a major role i regulation of homeostasis - receptors within hypothalamus monitor osmotic pressure, glucose level, certain hormone concentrations, and temperature of blood - major integrating link between nervous and endocrine
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Hypothalamus
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Small region on posterior aspect of diencephalon - includes the pineal gland
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Epithalamus
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Complex routing of efferent and afferent pathways
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Midbrain
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Controls certain visual reflexes to coordinate eye and head movement; also adjusts lens shape for close vs far focus
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Superior Colliculi
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Part of the auditory pathway - relays impulses from receptors in the ear to the thalamus - reflex centers for the startle response
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Inferior Colliculi
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Another section of the brain stem that serves as a bridge that connects parts of the brain with one another - important role in coordinating and maximizing efficiency of voluntary movements
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Pons
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Transition from spinal cord to brain stem - site of "decussation" - contains several different nuclei linked to vital body functions
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Medulla Oblongata
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Resides in the posterior fossa of cranial vault - accounts for about 10% of brain mass, but half of the neurons in the brain - subconscious fine tuning center for motor control
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Cerebellum
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Purely sensory - Sense of smell
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Olfactory Nerve
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Purely sensory - Passes through optic foramen of orbit - link to thalamus and then to primary visual area in occipital lobe of cerebral cortex
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Optic Nerve
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Mainly a motor nerve , but some sensory proprioception - Passes through superior orbital fissure - has superior and inferior branches that provide motor control of superior rectus, medial rectus, inferior rectus, inferior oblique - also feeds intrinsic smooth muscles for adjusting lens and iris - sensory aspect provides proprioceptive info about body position and movement
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Oculomotor Nerve
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Mainly a motor nerve, but some sensory - smallest of the 12 cranial nerves and the only one that arises from posterior aspect of brain stem - motor portion originates in nucleus of midbrain and passes through superior orbital fissure of orbit - controls superior oblique muscle - sensory aspect provides proprioceptive info from superior oblique
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Trochlear Nerve
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Largest of cranial nerves; both afferent and efferent functions - emerges from ventrolateral aspect of the pons - has three nerve branches: opthalmic, maxillary, and mandibular nerves - Sensory aspect: skin of face, nasal cavity, upper and lower teeth, upper lip, and mouth and tongue - Motor: muscles of mastication
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Trigeminal Nerve
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Mainly a motor nerve, but some sensory for proprioception - passes through superior orbital fissure - originates from a nucleus in the pons - motor control of lateral rectus muscle which abducts the eyeball
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Abducens Nerve
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Mixed cranial nerve, both sensory and motor functions - passes through internal auditory meatus of temporal bone - sensory: taste buds from anterior 2/3 of tongue; proprioceptors from muscles of face and scalp - motor: facial, scalp, and neck muscles - autonomic fibers control some glandular secretions
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Facial Nerve
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Mainly a sensory cranial nerve - passes through internal auditory meatus of temporal bone - two branches - input from semicircular canals of inner ear to the pons; impulses for equilibrium, sense of head position - impulses from cochlea of inner ear; impulses for hearing
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Vestibulocochlear Nerve
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Mixed cranial nerve- sensory functions; taste buds, proprioceptors in swallowing muscles, baroreceptors and chemoreceptors in and near carotid sinus and artery - motor: stylopharyngeus muscle dilates pharynx to facilitate swallowing - stimulates parotid glands to secrete saliva
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Glossopharyngeal Nerve
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Vagrant, wandering, wide distribution - mixed cranial nerve - sensory: skin of external ear, few taste buds, proprioceptors in muscles of neck and throat, baro and chemoreceptors near carotid arteries and aortic arch - visceral sensory receptors in many abdominal organs - efferent: autonomic output to heart, lungs, glands of GI tract, smooth muscle of respiratory and GI tracts
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Vagus
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Mixed cranial nerve but predominantly motor in function - different from all other cranial nerves in that it originates from both brain stem and spinal cord - cranial root: motor; from medulla through jugular foramen to swallowing muscles of pharynx, larynx, and soft palate - spinal: mostly motor; from superior spinal cord thru foramen magnum and then jugular foramen to sternocleidomastoid and trapezius muscles
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Accessory Nerve
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Mixed cranial nerve but predominatly motor in function - sensory: proprioceptors in tongue muscles to medulla - motor: muscles of the tongue that contribute to tongue movement, swallowing, and speech
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Hypoglossal Nerve
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Protection of lungs, heart, and great vessels - Important role in respiration
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Rib Cage
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The superior aspect of the sternum
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Manubrium
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Site of articulation with clavicle
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Clavicular Notch
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Middle and largest part of sternum
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Body
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Superior aspect of body - articulation with manubrium - backward tilt of manubrium relative to body - at level of t4-t5 and attachment sites for second ribs
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Sternal Angle
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Most inferior aspect
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Xiphoid Process
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7 superior ribs - those that articulate directly with sternum
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True Ribs
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Paris 8-10 - attach to sternum indirectly through the costal cartilage of 7th rib
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False Ribs
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Paris 11 & 12 - anchored only posteriorly, no anterior anchor
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Floating Ribs
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Ligamentous attachment to transverse process
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Tubercle
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Originates from the medulla of brain stem at foramen magnum - extends to level of L1-L2 in adults
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Spinal Cord
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From about C4 to T1; Nerves to and from upper limbs arise from this region
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Cervical Enlargement
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From about T9-T12; nerves to and from lower limbs arise from this region
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Lumbar Enlargement
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Tapered, conically shaped inferior end of the spinal cord
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Conus medullaris
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" Horse's Tail"; collection of spinal nerves inferior to conus medullaris that exit vertebral column in lumbar, sacral, and coccygeal regions
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Cauda Equina
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Located between wall of vertebral canal and dura mater
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Epidural Space
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Single outer layer around spinal cord - dense, irregular connective tissue - runs from foramen magnum to S2 - No attachment to surrounding bone
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Dura Mater
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Thin, middle layer - thin, loose arrays of connective tissue - subarachnoid space contains cerebrospinal fluid - shock absorption and suspension system for spinal cord and brain
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Arachnoid Membrane
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Thin, inner layer of connective tissue - adheres to surface of spinal cord and brain
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Pia Mater
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Posterior Gray Horns
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Afferent
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Lateral Horns
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Autonomic
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Anterior Horns
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Efferent
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Merger of dorsal, lateral, and ventral roots as they leave the spinal cord and exit the vertebral canal - Contain sensory, autonomic, and motor components - 31 pairs - being to branch as they exit vertebral column via intervertebral foramina
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Spinal Nerves
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Regions of skin innervated by sensory cutaneous branches of spinal nerves
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Dermatomes
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Paralysis of both lower limbs
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Paraplegia
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Paralysis of all four limbs
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Quadripelgia
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No function from neck down; ventilator needed
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C1-C3
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Diaphragm function retained; allows breathing
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C4-C5
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Some arm and chest muscle function; allows feeding
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C6-C7
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Intact arm function
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T1-T3
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Control of trunk above umbilicus
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T4-T9
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Most leg muscle function intact; walking with braces
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L1-L2
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- Deep to the platysma, 2-headed origin, large muscle of anterior neck
- Origin: Manubrium of the sternum and anterior aspect of medial-clavicle - Insertion: Mastoid process of the temporal bone - Action: both: extension of atlanto-occipital joint, flexion of cervical spine opposite: lateral flexion to same side - Innervation: Spinal accessory |
Sternocleidomastoid
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- Fusiform muscles deep to sternocleidomastoid
- Origin: Transverse processes of cervical vertebrae - Insertion: First two ribs - Action: both: elevate ribs (inspiration) one side: rotate neck to opposite side, lateral flexion of neck to the same side - Innervation: Cervical Nerves |
Scalenes
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- Broad muscles in posterior aspect of the neck, deep to trapezius
- Origin: lower half of ligamentum nuchae and spinous processes of C7-T3/4 - Insertion: lateral occipital bone and mastoid process - Action: Both: extension of atlanto-occipital joint and cervical vertebrae One side: rotation and lateral flexion to same side - Innervation: Cervical Nerves |
Splenius Capitis
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- Immediately inferior to splenius capitus
- Origin: Spinous processes of T3-T6 - Insertion: Transverse processes of C1-C3 - Action: Both: Extension of cervical vertebrae One Side: rotation and lateral flexion of cervical spine to same side - Innervation: Cervical Nerves |
Splenius Cervicis
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Pull hyoid bone superiorly, which opens esophagus and closes larynx
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Suprahyoid Muscles
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Pull hyoid bone inferiorly into normal position after swallowing which reopens the airway
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Infrahyoid muscles
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Squeeze the pharnyx to push food into esophagus
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Pharyngeal Constrictors
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- Flat, fan-shaped muscle
- Origin: Interior aspect of anterior mandible - Insertion: Inferior tongue and hyoid - Action: Depresses tongue, thrusts tongue forward - Innervation: Hypoglossal Nerve |
Genioglossus
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- Flat Muscle
- Origin: Greater horn and body of hyoid - Insertion: Side of tongue - Action: Depresses tongue, draws down sides of tongue, pulls tongue backward - Innervation: Hypoglossal Nerve |
Hypoglossus
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- Bipartitie muscle with a central intermediate tendon, anterior and posterior bellies
- Origin: Anterior: inferior margin of interior mandible Posterior: mastoid process - Insertion: Pulley of hyoid - Action: Swallowing, opening mouth, stabilizes hyoid during speech - Innervation: trigeminal and facial nerves |
Digastric
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- Narrow strap-like muscles inferior to genioglossus, internal mandible
- Origin: Internal mandible near midline - Insertion: Anteior hyoid bone - Action: Contributes to swallowing, widens pharynx - Innervation: Hypoglossal |
Geniohyoid
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- Flat, triangular muscles inferior to geniohyoid and superior to diagnostic; forms floor of mouth
- Origin: Along internal surface of mandible, jaw - Insertion: Anterior hyoid bone - Action: Elevates floor of mouth allowing tongue to push food back into pharynx - Innervation: Trigeminal |
Mylohyoid
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- Narrow, strap-like muscles; parallels posterior belly of digastric
- Origin: Styloid process of temporal bone - Insertion: lateral hyoid bone - Action: Lifts hyoid bone for swallowing - Innervation: Trigeminal |
Stylohyoid
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- Narrow, strap-like muscles; parallels posterior belly of digastric
- Origin: Styloid process of temporal bone - Insertion: Lateral hyoid bone for swallowing - Innervation: Trigeminal |
Sternohyoid
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- Strap-like muscles with superior and inferior bellies and an intermediate tendon
- Origin: Superior Scapula - Insertion: Hyoid bone lateral to sternohyoid - Action: Depresses hyoid bone after swallowing; opens airway - Innervation: C1-C3 |
Omohyoid
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- Lateral to and beneath to omohyoid
- Origin: thyroid cartilage of larynx - Insertion: Hyoid bone lateral to omohyoid - Action: Works with sternothyroid; depresses hyoid after swallowing; opens airway - Innervation: C1-C3 |
Thyrohyoid
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- Deep to sternohyoid
- Origin: Manubrium of sternum - Insertion: Thyroid cartilage - Action: Depresses thyroid cartilage of larynx; works with thyrohyoid muscle; influences high/low tones of voice - Innervation: C1-C3 |
Sternothyroid
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- Deepest and most superior of the three constrictors
- Origin: Mandible - Insertion: Midline of posterior pharynx - Action: Constricts pharynx; assists with swallowing - Innervation: Glossopharyngeal and Vagus |
Superior Pharyngeal Constrictor
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