Popular in Anatomy and Physiology I
Popular in Science
This 18 page Bundle was uploaded by kgrunwaldt on Monday January 25, 2016. The Bundle belongs to BIOL 214 at Truman State University taught by Dr. Guffey in Spring 2016. Since its upload, it has received 32 views. For similar materials see Anatomy and Physiology I in Science at Truman State University.
Reviews for Skeleton Notes
Report this Material
What is Karma?
Karma is the currency of StudySoup.
You can buy or earn more Karma at anytime and redeem it for class notes, study guides, flashcards, and more!
Date Created: 01/25/16
The Skeleton The Axial Skeleton Axial Skeleton structured from 80 bones segregated into three major reasons skull vertebral column and thoracic cage Forms the longitudinal axis of the body Supports the head neck and trunk Protects the brain spinal cord and organs in the thorax Skull Bones Overview Frontal forms forehead superior parts of orbits and most of the anterior cranial fossa also contains sinuses Parietal form most of the superior and lateral aspects of the skull Occipital forms posterior aspect and most of the base of the skull Temporal form inferolateral aspects of the skull and contributes to the middle cranial fossa has squamous mastoid tympanic and petrous regions Sphenoid keystone of the cranium contributes to the middle cranial fossa and orbits main parts are the body greater wings lesser wings and pterygoid processes Ethmoid helped to form the anterior cranial fossa forms part of the nasal septum and the lateral walls and roof of the nasal cavity contributes to the medial wall of the orbit o Auditory Ossicles malleus incus and stapes found in middle ear cavity involved in sound transmission Mandible the lower jaw Maxilla keystone bones of the face form the upper jaw and parts of the hard palate orbits and nasal cavity walls Zygomatic form the cheeks and part of the orbits Nasal form the bridge of the nose Lacrimal form part of the medial orbit walls Palatine form posterior part of the hard palate and a small part of the nasal cavity and orbit walls Vomer inferior part of the nasal septum Inferior Nasal Concha form part of the lateral walls of the nasal cavity The Skull Skull the body s most complex bony structure 0 Formed by 22 total cranial and facial bones Cranium encloses and protects the fragile brain and furnishes attachment sites for the head and neck muscles Facial Bone Functions 0 Form the framework of the face 0 Contain cavities for the special sense organs of sight taste and smell 0 Provide openings for air and food passage 0 Secure the teeth 0 Anchor the facial muscles of expressions Most skull bones are flat bones except for the mandible Sutures interlocking joints that unite the bones 0 Include coronal sagittal squamous and lambdoid sutures Cranium Eight cranial bones are the paired parietal and temporal bones and unpaired frontal occipital sphenoid and ethmoid bones Frontal Bone shellshaped bone that forms the anterior cranium o Articulates posteriorly with the paired parietal bones via the coronal suture 0 Most anterior part of the frontal bone is the squamous part or forehead O Supraorbital Margins the thickened superior margins of the orbits that lie under the eyebrows I Where the frontal squamous region ends 0 Anterior Cranial Fossa supports the frontal lobes of the brain 0 Supraorbital Foramen notch allows the supraorbital artery and nerve to pass to the forehead O Glabella the smooth portion of the frontal bone between the orbits Parietal Bones and Major Sutures 0 Parietal Bones large curved rectangular bones that form most of the superior and lateral aspects of the skull 0 Four largest sutures occur where the parietal bones form a joint with other cranial bones I Coronal Suture where the parietal bones meet the frontal bone anteriorly I Sagittal Suture where the parietal bones meet superiorly at the cranial midline I Lambdoid Suture where the parietal bones meet the occipital bone posteriorly I Squamous Suture where a parietal and temporal bone meet on the lateral aspect of the skull Occipital Bone forms most of the skull s posterior wall and base 0 Articulates anteriorly with the paired parietal and temporal bones via the lambdoid and occipitomastoid sutures 0 Joins with the sphenoid bone in the cranial floor via its basilar region which bears a midline projection called the pharyngeal tubercle 0 Posterior Cranial Fossa supports the cerebellum of the brain 0 Foramen Magnum base of the occipital bone through which the inferior part of the brain connects with the spinal cord 0 Occipital Condyles articulate with the first vertebra of the spinal column in a way that permits a nodding yes motion of the head 0 Hypoglossal Canal hidden medially and superiorly to each occipital condyle 0 External Occipital Protuberance a median protrusion superior to the foramen magnum Temporal Bones lie inferior to the parietal bones and meet them at the squamous sutures 0 Squamous Region borders the squamous suture 0 Zygomatic Process barlike process that meets the zygomatic bone of the face anteriorly 0 Zygomatic Arch the projection of the cheekbone 0 Mandibular Fossa small oval fossa that lies on the inferior surface of the zygomatic process that receives the condyle of the mandible o Tympanic Region eardrum region of the temporal bone 0 External Acoustic Meatus external ear canal through which sound enters the ear 0 Styloid Process an attachment point for several tongue and neck muscles and for a ligament that secures the hyoid bone of the neck to the skull 0 Mastoid Region exhibits the mastoid process 0 Mastoid Process an anchoring site for neck muscles 0 Stylomastoid Foramen foramen between the styloid and mastoid processes that allows cranial nerve VII the facial nerve to leave the skull 0 Mastoid Sinuses air cavities in the mastoid process 0 Petrous contributes to the cranial base 0 Middle Cranial Fossa created by the sphenoid bone and petrous portions 0 Jugular Foramen located at the junction of the occipital and petrous temporal bones and allows passage of the internal jugular vein and three cranial nerves IX X and XI 0 Carotid Canal anterior to the jugular foramen transmits the internal carotid artery into the cranial cavity 0 Foramen Lacerum a jagged opening between the petrous temporal bone and the sphenoid bone 0 Internal Acoustic Meatus positioned superolateral to the jugular foramen and transmits cranial nerves VII and VIII Sphenoid Bone batshaped bone that spans the width of the middle cranial tossa 0 Sphenoid Sinuses located within the body of the sphenoid 0 Sella Turcica saddleshaped prominence 0 Hypophyseal Fossa seat of the saddle that forms a snug enclosure for the pituitary gland 0 Greater Wings project laterally from the sphenoid body I Form I The middle cranial tossa I The dorsal walls of the orbits I The external wall of the skull 0 Lesser Wings form part of the floor of the anterior cranial tossa and part of the medial walls of the orbits 0 Pterygoid Processes project interiorly from the junction of the body and the greater wings 0 Optic Canals lie anterior to the sella turcica and allow the optic nerves cranial nerves II to pass to the eyes 0 Superior Orbital Fissure a long slit between the greater and lesser wings that allows cranial nerves that control eye movements III IV and VI to enter the orbit 0 Foramen Rotundum in the medial part of the greater wing usually oval and provides passageways for branches of cranial nerve V the maxillary and mandibular nerves 0 Foramen Ovale a large oval foramen posterior to the foramen rotundum that also provides passageways for branches of cranial nerve V 0 Foramen Spinosum posterolateral to the foramen ovale transmits the middle meningeal artery Ethmoid Bone has a complex shape 0 Cribriform Plates help form the roof of the nasal cavities and the floor of the anterior cranial fossa 0 Crista Galli triangular process that is attached to the outermost covering of the brain 0 Perpendicular Plate projects inferiorly in the median plane and forms the superior part of the nasal septum dividing it into right and left halves 0 Lateral Mass flanks the perpendicular plate on each side and contains ethmoid sinuses 0 Superior and Middle Nasal Conchae protrude into the nasal cavity 0 Orbital Plates lateral surfaces of the ethmoid lateral masses and contribute to the medial walls of the orbits Sutural Bones tiny irregularly shaped bones or bone clusters that occur within sutures most often in the lambdoid suture contain no significance Facial Bones Mandible Ushaped lowerjawbone largest strongest bone of the face 0 Mandibular Angle where the ramus of the mandible meet posteriorly 0 Mandibular Notch located at the superior margin of each ramus that separates the coronoid process and the mandibular condyle O Coronoid Process an insertion point for the large temporalis muscle that elevates the lower jaw when chewing 0 Mandibular Condyle articulates with the mandibular fossa of the temporal bone 0 Alveolar Margin contains the sockets in which teeth are embedded 0 Mandibular Symphysis a slight depression in the midline of the mandibular body that indicates where the two mandibular bones fused during infancy 0 Mandibular Foramina located on the medial surface of each ramus permit the nerves responsible for tooth sensation to pass to the teeth in the lower jaw 0 Mental Foramina openings on the lateral aspects of the mandibular body that allow blood vessels and nerves to pass to the skin of the chin and lower ip Maxillary Bones fused medially form the upper jaw and the central portion of the facial skeleton 0 Alveolar Margins where the maxillae carry the upper teeth 0 Anterior Nasal Spine where the nose and maxillae meet medially 0 Palatine Processes project posteriorly from the alveolar margins and fuse medially at the intermaxillary suture forming the anterior twothirds of the hard palate or bony roof of the mouth 0 Incisive Fossa posterior to the teeth serves as a passageway for blood vessels and nerves 0 Frontal Processes extend superiorly to the frontal bone forming part of the lateral aspects of the bridge of the nose and contain the maxillary sinuses I Maxillary Sinuses the largest of the paranasal sinuses and extend from the orbits to the roots of the upper teeth 0 Zygomatic Processes where the maxillae articulate with the zygomatic bones 0 Inferior Orbital Fissure located deep within the orbit at the junction of the maxilla with the greater wing of the sphenoid permits the zygomatic nerve the maxillary nerve a branch of cranial nerve V and blood vessels to pass to the face 0 lnfraorbital Foramen below the eye socket allow the infraorbital nerve a continuation of the maxillary nerve and artery to reach the face Zygomatic Bones irregularly shaped bones 0 Commonly called the cheekbones o Articulate with the zygomatic processes of the temporal bones posteriorly the zygomatic process of the frontal bones superiorly and with the zygomatic processes of the maxillae anteriorly 0 Form the prominence of the cheeks and part of the inferolateral magins of the orbits Nasal Bones thin basically rectangular bones o Fused medially forming the bridge of the nose 0 Articulate with the frontal bone superiorly the maxillary bones laterally and the perpendicular plate of the ethmoid bone posteriorly o lnferiorly they attach to the cartilages that form most of the skeleton and the external nose Lacrimal Bones delicate fingernailshaped bones 0 Contribute to the medial walls of each orbit o Articulate with the frontal bone superiorly the ethmoid bone posteriorly and the maxillae anteriorly 0 Lacrimal Fossa deep groove in acrima bones that houses the acrima sac part of the passageway that allows tears to drain from the eye surface into the nasal cavity Palatine Bones Lshaped bones o Fashioned from the horizontal plate and the perpendicular plate 0 Has three important articular processes I Pyramidal process I Sphenoidal process I Orbital process 0 Horizontal Plates joined at the median of the median palatine suture complete the posterior portion of the hard palate 0 Perpendicular Plates project superiorly form part of the posterolateral walls of the nasal cavity and a small part of the orbits Vomer slender plowshaped bone 0 Lies in the nasal cavity and forms part of the nasal septum Inferior Nasal Conchae thin curved bones in the nasal cavity 0 Project medially from the lateral walls of the nasal cavity just inferior to the middle nasal conchae of the ethmoid bone 0 Largest of the three pairs of conchae and form part of the lateral walls of the nasal cavity Hyoid Bone Not considered to be part of the skull Lies just inferior to the mandible in the anterior neck It is the only bone of the body that does not articulate directly with any other bone Anchored by narrow stylohyoid ligaments to the styloid processes of the temporal bones Horseshoeshaped bone Acts like a movable base for the tongue Has attachment points for neck muscles that raise and lower the larynx during swallowing and speech Special Characteristics of the Orbits and Nasal Cavitv Orbits bony cavities in which the eyes are firmly encases and cushioned by fatty tissue 0 Also contains muscles that move the eyes and tearproducing acrima glands o Formed by parts of seven bones I Frontal I Sphenoid I Zygomatic I Maxilla I Palatine I Lacrimal I Ethmoid 0 Also contains superior and inferior orbital fissures and optic canals Nasal Cavity constructed of bone and hyaline cartilage 0 Roof is formed by cribriform plates of the ethmoid bone 0 Lateral walls are largely shaped by the superior and middle conchae of the ethmoid bone the perpendicular plates of the palatine bones and the inferior nasalconchae 0 Floor of the nasal cavity is formed by the palatine processes of the maxillae and palatine bones o Divided into right and left parts by the nasal septum 0 Paranasal Sinuses cluster around the nasal cavity I Bony portion of the septum is formed by the vomer inferiorly and the perpendicular plate of the ethmoid bone superiorly I Septal cartilage completes the septum anteriorly The Vertebral Column General Characteristics 0 Also called the spine or the spinal column 0 Consists of 26 irregular bones connected in such a way that a flexible curved structure results 0 Extends from the skull to the pelvis 0 Surrounds and protects the delicate spinal cord and provides attachment points for the ribs and for the muscles of the back and neck 0 In a fetus and infant the vertebral column consists of 33 separate bones or vertebrae I Nine of these eventually fuse to form two composite bones the sacrum and the coccyx Regions 0 Cervical Vertebrae seven vertebrae of the neck 0 Thoracic Vertebrae next twelve vertebrae O Lumbar Vertebrae five vertebrae supporting the lower back 0 Sacrum articulates with the hip bones of the pelvis 0 Coccyx terminus of the vertebral column Ligaments 0 Anterior and Posterior Longitudinal Ligaments run as continuous bands down the front and back surfaces of the vertebrae from the neck to the sacrum 0 Ligamentum Flavum connects adjacent vertebrae contains elastic connective tissue and is especially strong Intervertebral Discs cushionlike pads composed of two parts 0 Nucleus Pulposus acts like a rubber ball giving the disc elasticity and compressibility 0 Anulus Fibrosus strong collar composed of collagen fibers superficially and fibrocartilage internally o Intervertebral discs act like shock absorbers 0 HerniatedProlapsed Disc involves the rupture of the anulus fibrosus followed by a protrusion of the spongy nucleus pulposus through the anulus General Structures 0 BodyCentrum discshaped weightbearing region 0 Vertebral Arch posterior to the vertebra I Both body and vertebral arch form the vertebral foramen 0 Vertebral Foramen an opening in the vertebra 0 Vertebral Canal where the spinal cord passes through 0 Pedicles short bony pillars projecting posteriorly from the vertebral body 0 Laminae flattened plates that fuse in the median plane 0 Intervertebral Foramina adjacent vertebrae 0 Spinous Process a median posterior projection arising at the junction of the two laminae 0 Transverse Process extends laterally from each side of the vertebral arch 0 Superior and Interior Articular Processes protrude from the pediclelamina junctions Regional Vertebral Characteristics 0 Flexion and extension 0 Lateral flexion O Rotation Cervical Vertebrae o Identified as C1C7 o Smallest lightest vertebrae 0 Characteristics of C3C7 I Body is oval I Spinous process is short projects directly back and is spit at its tip except for C7 I Spinous process for C7 is not split at its tip and is larger than the other vertebrae I C7 is known as the vertebra prominens because its spinous process is palpable through the skin I Vertebral foramen is large and triangular I Each transverse process contains a transverse foramen through which the vertebral arteries pass to service the brain 0 First two cervical vertebrae are known as the atlas and the axis I More robust than the typical vertebra I Have no intervertebral discs I Highly modified I Atlas C1 has no body and no spinous process I Axis C2 has a body and the other typical vertebral processes and is not as specialized as the atlas I Dens knob like projection that projects superiorly from the body of the axis Thoracic Vertebrae o 12 thoracic vertebrae T1T12 o All articulate with the ribs 0 Characteristics I Body is roughly heart shaped I Bears two demifacets on each side that receive the heads of the ribs I Vertebral foramen is circular I Spinous process is long and points sharply downwards I The transverse processes have facets the transverse costa facets that articulate with the tubercles of the ribs except for T11 and T12 I Superior and inferior facets lie mainly in the frontal plane I Lateral flexion is restricted by the ribs Lumbar Vertebrae o Receives the most stress 0 Five lumbar vertebrae L1L5 0 Sturdier structure with massive bodies and are kidneyshaped in a superior view 0 Characteristics I Pedicles and laminae are shorter and thicker than those of other vertebrae I Spinous processes are short flat and hatchet shaped and are easily seen when a person bends forward I Vertebral foramen is triangular I Orientation of the facets of the articular processes of the lumbar vertebrae differs substantially from that of the other vertebra types Modifications lock the lumbar vertebrae together and provide stability by preventing rotation of the lumbar spine I Flexion and extension are possible as well as lateral flexion Sacrum o Triangular 0 Forms the wall of the pelvis O Formed by five fused vertebrae S1 S5 0 Articulates superiorly with superior articular processes with L5 and inferiorly with the coccyx o Laterally articulates with its auricular surfaces with the two hip bones to form the sacroiliac joints of the pelvis 0 Sacral Promontory the anterosuperior margin of the first sacral vertebra 0 Transverse Ridges four ridges that cross its concave anterior aspect o Anterior Sacral Foramina lie at the lateral ends of the transverse ridges and transmit blood vessels and anterior rami of the sacral spinal nerves 0 Median Sacral Crest fused spinous processes of the sacral vertebrae o Posterior Sacral Foramina transmit the posterior rami of the sacral spinal nerves 0 Lateral Sacral Crests remnants of the transverse processes of S1 S5 0 Sacral Canal the vertebral canal that continues into the sacrum 0 Sacral Hiatus an enlarged external opening Coccyx 0 Small triangular bone 0 Consists of three four or five vertebrae fused together 0 Slightly supports the pelvic organs but is overall useless The Thoracic Caqe Elements include the thoracic vertebrae dorsally the ribs laterally and the sternal and costal cartilages anteriorly 0 Costal cartilages connect the ribs to the sternum Sternum breastbone that lies in the anterior midline of the thorax 0 Clavicular notches where the manubrium articulates with the clavicles 0 Jugular notch central indentation in the superior border of the manubrium 0 Sternal angle the horizontal ridge across the front of the sternum where the manubrium joins the sternal body 0 Xiphisternal joint the point where the sternal body and xiphoid process fuse Ribs twelve pairs that attach to the flaring sides of the thoracic cage 0 Vertebrosternal ribs true ribs superior seven rib pairs that attach directly to the sternum by individual costal cartilages o Vertebrochondral ribs false ribs the remaining five pairs of ribs that attach indirectly to the sternum or entirely lack a sternal attachment 0 Costal margin the inferior margin of the rib cage formed by the costal cartilages of ribs 71O o Vertebral ribs rib pairs 11 and 12 have no anterior attachments The Appendicular Skeleton Bones of the limbs and their girdles Appended to the axial skeleton that forms the longitudinal axis of the body Enables us to carry out the movements typical of our freewheeling and manipulative lifestyle Pectoral Girdle Consists of the clavicle anteriorly and the scapula posteriorly Attaches the upper limbs to the axial skeleton and provides attachment points for many of the muscles that move the upper limbs Allows a wide range of mobility because 0 Only the clavicle attaches to the axial skeleton so the scapula can move freely across the thorax allowing the arm to move with it o The socket of the shoulder joint is shallow and poorly reinforced so it does not restrict the movement of the humerus Shoulder dislocations are fairly common Clavicles slender doubly curved bones that can be felt along their entire course as they extend horizontally across the superior thorax 0 Sternal end attaches to the sternal manubrium o Acromial end articulates with the scapula 0 Not very strong and likely to fracture 0 Clavicles act as braces they hold the scapulae and arms out laterally 0 Also transmit compression forces from the upper limbs to the axial skeleton Scapulae thin triangular flat bones 0 Glenoid cavity small shallow fossa o Acromion enlarged roughened triangular projection o Acromioclavicular joint where the acromion articulates with the acromial end of the clavicle 0 Coracoid process projects anteriorly from the superior scapular border 0 Suprascapular notch where the coracoid process is bounded medially The Upper Limb Made up of thirty separate bones Humerus the sole bone of the arm typical long bone Head the proximal end of the humerus which fits into the glenoid cavity of the scapula that allows the arm to hang freely Anatomical neck immediately inferior to the head slight constriction Surgical neck most frequently fractured part of the humerus Deltoid tuberosity roughened attachment site for the deltoid muscle Radial groove runs obliquely down the posterior aspect of the shaft Trochlea medial condyle that looks like an hourglass tipped on its side Capitulum lateral condyle that is ball shaped Forearm composed of two parallel long bones the radius and the ulna 0 Also known as the antebrachium 0 Ulna slightly longer than the radius 0 Radius lateral to the ulna Hand include the bones of the carpus and the metacarpus 0 Carpals in Order Scaphoid Lunate Triquetrum Pisiform Trapezium Trapezoid Capitate Hamate 0 Five metacarpus make up the palm 0 Five fingers phalanges including pollex Pelvic Girdle Attaches the lower limbs to the axial skeleton transmits the full weight of the upper body to the lower limbs and supports the visceral organs of the pelvis Attached by the strongest ligaments in the body More stability less mobility Major bones include o llium large flaring bone that forms the superior region of the coxal bone 0 lschium posteroinferior part of the hip bone 0 Pubis anterior portion of the hip bone Lower Limb Carry the entire weight of the erect body and are subjected to exceptional forces when we jump or run Thicker and stronger than comparable bones of the upper limb Three segments include o Thigh I Consists of the femur the longest strongest bone in the body 0 Leg I Consists of two parallel bones the tibia and the fibula I Tibia receives the weight of the body from the femur and transmits it to the foot second strongest and longest bone I Fibula nonweight bearing bone but several muscles originate from it 0 Foot I Tarsus made up of seven bones called tarsals form the posterior half of the foot I Metatarsus consists of five small long bones called metatarsals I Phalanges 14 phalanges three phalanges in each digit except for the big toe or hallux which has two Develolomental Aspects of the Skeleton Fontanelles incomplete skull bones at birth connected by unossified remnants of fibrous membranes Primary curvatures thoracic and sacral curvatures Secondary curvatures cervical and lumbar curvatures
Are you sure you want to buy this material for
You're already Subscribed!
Looks like you've already subscribed to StudySoup, you won't need to purchase another subscription to get this material. To access this material simply click 'View Full Document'