Hi dear,

 Would you help me to finish this assignment with good quality and be on time please?

Students, please participate in a discussion about the material presented in Week 4, that is largely focusing on the Axial and Appendicular Skeleton. 

 You’ll find the attachments below .  All questions should be answered in 1-2 solid paragraphs. 

Also, per some questions I received about the Covid-19 vaccine, and why some minority communities do not trust the research, please listen to the below Podcast interviewing Dr. Angela Branche of the University of Rochester Medical Center who is working to recruit Black participants for Covid-19 vaccine trials. She explains why the diversity of the trials may affect who trusts the vaccine once it comes out. Please post your thoughts about this interview in the Discussion below.

Please remember that students are REQUIRED to participate in the Discussions by either posting their own original thoughts, or responding to a classmate’s post.

Use the below bullets to guide your remarks:

  All questions should be answered in 1-2 solid paragraphs.  

• What did you think?
• What did you learn?
• What surprised you?
• What did you disagree with?

Thank you!

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The Axial Skeleton

Objectives
• Identify the bones of the axial skeleton and specify their functions.
• Identify the bones of the cranium and face.
• Describe the differences between adult, child, and infant skulls.
• Identify and describe the curvatures of the spinal column.
• Identify the vertebral regions and give characteristics of each.
• Explain the articulations between the thoracic vertebrae, the ribs, and sternum.

Skeletal system includes both:
• Axial skeleton – 80 Bones

• Skull – 28 bones
• 8 cranial bones: frontal, parietal (2) occipital, temporal (2), sphenoid, ethmoid
• 14 facial bones: nasal (2), maxillae (2), zygomatic (2), palatine (2), vomer,

inferior nasal conchae (2), lacrimal (2), mandible
• Auditory ossicles (6 bones)

• 1 hyoid bone
• Vertebral column- 24 vertebrae, sacrum, cocyx
• Thoracic cage – 24 ribs and sternum

• Appendicular skeleton – 126 bones
• Pectoral and pelvic girdles – 6 bones
• Upper and lower limbs – 120 bones

• Total of 206 bones

The Axial Skeleton

The skull
• Consists of the cranium and the bones of the face

• The cranium encloses cranial cavity or cranial vault
• Facial bones surround and protect the entrances to the respiratory and digestive

tracts

Lab Experience

Locate the following axial skeleton landmarks on the plastic and natural bone specimens
in the lab.

DO NOT use your pen or pencil to point, use the supplied pipe cleaners

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List of Cranial Bones and Landmarks

Region View Bone Bone Landmarks
Cranium Frontal Frontal Supraorbital foramen

Nasal

Sphenoid Superior orbital fissure
Inferior orbital fissure
Optic foramen (canal)

Ethmoid Perpendicular plate
Superior nasal concha
Middle nasal concha

Inferior nasal concha

Lacrimal

Zygomatic

Mandible Body
Ramus
Alveolar processes
Angle
Mental foramen

Cranium Lateral Maxilla Infraorbital foramen

Mandible Coronoid process
Condylar process/Articular surface
Mandibular notch
Body
Ramus
Mental foramen

Zygomatic Temporal process

Temporal Zygomatic process
Styloid process
Mastoid process
External auditory (acoustic) meatus

Sphenoid Greater wing

Other Bones Nasal, Lacrimal, Occipital, Frontal

Other Landmarks Coronal suture, Squamous suture,
Lambdoid suture,
Sagittal suture (superior view)

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Region View Bone Bone Landmarks
Cranial Floor Superior Frontal Frontal sinus (not always visible)
w/ calvaria removed

Ethmoid Cribiform plate
Olfactory foramina
Crista galli

Sphenoid Sella turcica (Pituitary fossa)
Greater wing
Lesser wing

Temporal Pterous portion

Occipital Foramen magnum

Cranium Inferior Maxilla Palatine process (hard palate)
w/ mandible removed Palatine Horizontal plate (hard palate)

Vomer

Sphenoid

Temporal Mastoid process
Styloid process
Mandibular process

Occipital External occipital protuberance
Foramen magnum
Occipital condyles

Orbit Frontal Orbital Bones Frontal, Maxilla, Zygomatic,
Lacrimal, Ethmoid, Sphenoid,
Palatine

Nasal Cavity Frontal Ethmoid Middle nasal concha, Perpindicular plate
Boney septum Vomer
Inferior nasal concha
Nasal Sinuses Frontal Bones w/ sinuses Frontal sinus, Sphenoidal sinus,

Ethmoidal sinus, Maxillary sinus
Sutures

Coronal – Between Frontal & Parietal
Sagittal – Between Parietals
Lambdoidal – Between Parietals & Occipital
Squamous – Between Parietals & Temporals

Fetal Skull
Anterior (frontal) fontanel
Posterior (occipital) fontanel
Sphenoidal (anterolateral) fontanel
Mastoid (posterolateral) fontanel

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Vertebral Column
Divisions

Cervical (7)
Thoracic (12)
Lumbar (5)
Sacral (5 fused into 1 bone) & Coccygeal (3-5 fused into 1 bone)

Curves
Each region has its own curve
Primary Curves – Thoracic and sacral form “C” shape in infant
Secondary Curves – Cervical develops when supporting head, lumbar develops
when supporting body weight while sitting

Bony Landmarks
Typical Vertebrae

Body
Pedicle
Lamina
Vertebral arch
Spinous process
Transverse processes
Superior articular process and facet
Inferior articular process and facet
Vertebral foramen
Intervertebral notch – forms Intervertebral foramen when 2 vertebrae articulate

Regional Differences

Cervical
Smallest
C1 also called Atlas, C2 also called Axis form atlantoaxial joint
C1 mostly a bony ring, C2 contains the Dens or Odontoid process
Allows for turning head as in saying No
C2 – C6 contain bifid spinous processes
C7 has a large spinous process called vertebra prominens

Thoracic
Medium sized
Downward projecting spinous processes
Presence of facets for rib articulations

Lumbar
Largest
Blunt projections

Sacrum
Base Median sacral crest
Apex Auricular surface
Sacral foramina Ala or wing
Sacral canal Sacral hiatus

Coccyx

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Thoracic Cage

Sternum
Manibrium Jugular notch
Body Clavicular notch
Xiphoid process

Ribs
12 pair (in both male and female!)
True ribs (vertebrosternal) – Ribs 1 – 7
False ribs (vertebrochondral) –Ribs 8-12
*Ribs 11 & 12 are floating ribs (false ribs, but not vertebrochondral)

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The Appendicular Skeleton
Objectives
• Identify the bones of the pectoral girdle and upper limbs, their functions and their

features.
• Identify the bones of the pelvic girdle and lower limbs, their functions and their

features.
• Compare the male and female pelvic structure.
• Explain how the skeleton can reveal significant information about the individual.
• Compare male and female skeletons.
• Describe the effect of aging on the skeleton.

The Pectoral Girdle

Pectoral girdle (shoulder girdle)
• Articulates the upper limbs with the trunk/axial skeleton at the sternoclavicular joint
• Consists of the clavicle and scapula articulating at the acromioclavicular joint
• Not a complete girdle as there is no posterior bony union
• This results in great range of motion, but joint instability

Clavicle
Bony landmarks: acromial end, sternal end, conoid tubercle (inferior aspect),
be able to distinguish left clavicle from right clavicle

Scapula
Spine Superior border
Acrimion process Superior angle
Supraspinous fossa Inferior angle
Infraspinous fossa Glenoid fossa (cavity)
Subscapular fossa Coracoid process
Superior border Medial (vertebral) border
Lateral (axillary) border

Upper Limbs (60 bones total)
• Scapula articulates with upper limb via humerus at the glenohumoral joint

Humerus
• Articulates with scapula at glenohumeral joint; and radius and ulna at the elbow joint

Head Medial epicondyle
Anatomical neck Lateral epicondyle
Surgical neck Trochlea
Greater tubercle Capitulum
Lesser tubercle Coronoid fossa (anterior)
Intertubercular groove Radial fossa (anterior)
Deltoid tuberosity Olecranon fossa (posterior)

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Radius
Head Styloid process
Neck Notch
Tuberosity

Ulna
Olecranon process Styloid process
Coronoid process Head (distal)
Trochlear (semilunar) notch Tuberosity
Radial notch

Carpal Bones and Hand
• Carpus forms wrist
• Carpals are two rows of four bones (eight total bones)

Proximal row starting at thumb: scaphoid, lunate, triquitrum, pisiform
Distal row: trapezium, trapezoid, capitate, hamate
Mnemonic: Some lovers try positions that they can’t handle

• Metacarpals of hand: Numbered I – V starting at thumb using Roman numerals
• Fingers comprised of phalanges (phalanx, singular)

Each finger has three phlanges, Pollex (thumb) has two
Fingers numbered I – V starting at thumb, but each does have it’s own name:
thumb or pollex, index, middle, ring, little

The Pelvic Girdle and Lower Limbs

The Pelvic Girdle
• More massive than the pectoral girdle, less mobility, more stability
• Consists of two os coxae

• Fusion of ilium, ischium, and pubis into a single bone (by 12-16 yrs.)
Ilium

Iliac crest Posterior superior iliac spine
Anterior superior iliac spine Posterior inferior iliac spine
Anterior inferior iliac spine Greater sciatic notch
Iliac fossa Auricular fossa

Ischium
Ischial spine Ischial tuberosity
Ramus
Lesser sciatic notch

Pubis
Pubic symphysis (symphysis pubis) Tubercle
Superior ramus Inferior ramus

Pelvis
• Composed of the hipbones, sacrum, and coccyx
• Subdivided into the false (greater) and true (lesser) pelvis
• Pelvic brim divides the above

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Male vs. Female Pelvis
The female pelvis has the following distinctions:

Greater pelvic outlet: greater distance between ischial spines
Flared ilia
Greater distance between PSIS, showing therefore more sacrum
Subpubic angle is greater than 100° (Males are less than 90°)

Lower Limbs (60 bones total)
• Femur is the longest bone in the body

• Articulates with the tibia at the knee
• Patella is a large sesamoid bone
• Fibula parallels tibia laterally

Femur
Head Medial condyle
Fovea capitus Lateral condyle
Neck Intercondylar fossa
Greater trochanter Medial epicondyle
Lesser trochanter Lateral epicondyle
Intertrochanteric crest (posterior) Patellar surface
Intertrochanteric line (anterior) Linea aspera

Tibia
Medial condyle Tuberosity
Lateral condyle Medial malleolus
Intercondylar eminence

Fibula
Head Lateral malleolus

Patella
Sesamoid bone that provides mechanical advantage to muscular forces at knee

Tarsal bones and Foot
• Seven tarsal bones: talus (articulates with tibia), calcaneus (heel), cuboid, navicular,

cuneiforms (medial, intermediate, lateral; or 1st, 2nd & 3rd)
• Pattern of metatarsal bones and phalanges parallels that of the hand
• When standing, body weight is mostly transferred from the talus to the calcaneus

• Rest is passed on to metatarsals
• Weight transfer occurs along longitudinal arch

• Transverse arch also exists

The Axial Skeleton

Spina Bifida

Homeostatic Regulation of Ca2+
Concentration in Blood

Age and Dietary Related Changes to Bone

Osgood-
Schlatter
Disease

Sever’s Disease

Little League Elbow

Avulsion
Fracture

Compression Fracture