Functions

• Support: body structure and shape

• Protection: vital organs surrounded

• Movement/Anchorage of Muscles

• Mineral Storage: calcium & phosphorus

• Blood Formation

Formation and structure

• Composed of connective tissue called osseous tissue and rich supply of blood vessels and nerves

• Osseous tissue is composed of : _______________

Bone Formation

• Skeleton fully formed by 2nd month of fetal development (all cartilage)

• Ossification (replacement of cartilage with bone cells and calcium salts) begins after 8th week of fetal development

• Childhood and adolescence: ossification ______ bone loss

• Early adulthood through middle age: ossification ______ bone loss

• After age 35: bone loss _______ ossification

Bone Formation/Ossification

Ossification: replacement of cartilage with bone• Cells:

– osteoblast: produce immature bony tissue that replaces cartilage (the “builders”)

– osteocyte: nourishes and maintains bone

– osteoclast: reabsorb or digest bone (the “remodelers”)

• Osteoblasts and osteoclasts work to deposit and tear down bone throughout life

Bone Growth

• Grow in length at the epiphyseal line

• Grow in width by addition of bone to the surface

• Controlled by anterior pituitary (GH)

Bone Composition

• Proper formation of bone depends on sources of calcium, phosphorous, and vitamin D.

• Vit. D helps with absorption of ________• Once Calcium and phosphorous are in the blood

osteoblastic activity forms the enzyme Calcium phosphate

• Calcium phosphate: gives bone its characteristic _________________

• Collagen: chief organic constituent (protein)

Bones (cont’d.)

• Bone is the reservoir for calcium storage• Calcium necessary for nerve transmittal to muscle

When insufficient, it interferes with nerve transmission causing muscle weakness and spasms

• Ca level maintained by the _______________, which secretes a hormone to release calcium from bone

Types of Bones Based on Composition

• Compact

• Cancellous

Compact Bone (Cortical)

• Dense, Stress Bearing

• Haversian Systems: system of small canals which contain blood vessels that bring _____and _____ to bone and remove waste products

• Medullary cavity: central shaft of long bone composed of _______ marrow (stores fat cells)

Cancellous Bone (spongy/trabecular)

• Light, spongy

• Found at ____________, ribs, sternum, hips, vertebrae, cranium spaces

• Contain red bone marrow with elements for blood formation

Bone Markings - Purpose

• Join one bone to another

• Provide a surface for attachment of muscles

• Create an opening for passage of blood vessels and nerves

• Use as landmarks

Major types of Bone Markings

• Processes/Projections: serve as attachments for muscles and tendons

• Depressions: openings or hollow regions help join bones or serve as passageways __________________

• Ridges - ____________________

Bone Processes and Depressions (cont’d.)

Bones by Shapes

Reference: Gerdin, Judith. Health Careers Today. 3rd edition. Mosby, 2003

Long Bones

• Extremities (Femur, tibia, fibula, humerus, ulna, radius, clavicle

• Act as ______

• Epiphysis: at the _____; covered with hyaline cartilage for articulating bones (provides ______); cancellous bone

• Epiphyseal line or plate: growth plate

• Diaphysis: shaft, covered with periosteum, contains ______bone marrow

• Medullary cavity – located in the shaft of a long bone. This cavity is surrounded by compact bone and lined with endosteum and contains _______ bone marrow

• Metaphysis: flared portion of the bone

Periosteum

• Dense, fibrous membrane covering bone

• Contains blood vessels

• Essential for bone cell survival and bone formation

Bone Structure (cont’d.)

(A) Divisions of a long bone and interior structure

(B) composition of compact (cortical) bone

Short Bones

• _____-shaped• Allows ____________• Cancellous bone

covered by compact bone

• Carpals, metacarpals, tarsals, metatarsals, phalanges

Flat Bones

• Flat plates• Protect ____________• Provide broad surface

area for attachment of ________

• Cranial bones, Facial bones, Scapula, Sternum

Irregular Bones

• Peculiarly shaped to provide support and protection with ____________

• Vertebrae, Ribs, Ear, Hip, Hyoid

• Includes Sesamoid bones

Sesamoid Bones

• Extra bones found around ________i.e. Patella

CARTILAGE

• Smooth, rubbery, white connective tissue

• Acts as a _____________ between bones

• Makes up the flexible parts of the skeleton as well as the ____________________– ___________– covers the surfaces of the bones

that form joints– __________– curved, fibrous cartilage found in

some joints (knee and jaw)

JOINTS

• _________ – jagged lines where bones joint that does not move (top of an adult’s skull – coronal /Sagittal sutures)

• __________ –Cartilaginous joint –2 bones join and are held firmly together; function as one (pelvic symphyses)

• ______________– movable– Ball and socket (hip)– Hinge (knee, elbow)

STRUCTURES OF SYNOVIAL JOINT

Bursae

• Closed sacks of synovial fluid with a synovial membrane located near, but not within a joint. Needed where sliding must take place

• Common sites: – between tendons (connective tissue connecting muscle

to bone) and bones

– between ligaments (binding bone to bone) and bone

– between skin and bones (with prominent bony anatomy)

Joints

Bones of the Body

SKELETON

• AXIAL SKELETON (80 BONES) – Skull

– Spinal Column

– Ribs

– Sternum

• APPENDICULAR SKELETON (126 bones)– Upper extremities

– Lower extremities

Skull - Cranium

• Houses and protects the brain

• _______: forms forehead • ________: forms roof of

nasal cavity• _______right & left; form

sides and roof of skull• ________: right & left;

forms temple, cheek, ear openings

• _______: back of skull; inferior portion has foramen magnum (opening for spinal cord) and 2 condyles to articulate with atlas

• _________: fills space between orbital plates; depression called sella turcica holds the pituitary gland; bat shaped

Cranial Sutures

• Unite the bones of the cranium

• As the child grow, irregular bands of connective tissue ossifies and turns into hard bone

Sutures

• _________Suture: between the frontal and parietal bones

• _________ Suture: between right and left parietal bones

• ________Suture: between the parietal and occipital bones

• _________ Suture: between temporal and parietal bones

Fontanels

• Fusion of the cranial bones is not complete at birth

• Space between the bones remains

• Anterior (Bregmatic): “soft spot”, closes at ___months

• Posterior (Occipital): triangular, closes at _____ months

BONES OF THE FACE

Facial Bones Continued

• ______ (2): cheek bones

• ______ (2): small bones form medial wall of each eye socket

• _______ (2): forms back roof of mouth and floor of nose

• ________(2): forms curved ledge inside side wall of nose

Ear Bones

• Malleus (2): the hammer

• Incus (2): the anvil

• Stapes (2): the stirrup

Hyoid Bone

• U-shaped bone

• In neck

• At base of tongue

• Only bone in body that does NOT articulate with another bone

SPINAL/VERTEBRAL COLUMN

• 26 Vertebrae• Five divisions

– C1 to C7 = Cervical– T1-T12 = Thoracic– L1-L5 = Lumbar– Sacrum (5 bones

fuse when young)– Coccyx (4 bones

fused together)

Functions

• Supports trunk and _____.

• Protects ____________

• Multiple joint spaces allow for ______ and twisting

BONES OF THE THORACIC CAVITY

• RIBS – 12 pairs, called ______ (first 7 = true, RIBS 8-12 = false ribs;

last 2 pairs = floating)

• _________– breast bone– Manubrium– Body– Xiphoid process (cartilage)

Functions

• Protect and support heart and ______

• Supports bones of pectoral girdle

• Plays leading role in ________

• Ribs and sternum aid in RBC formation

Appendicular Skeleton – 126 Bones

Shoulder Girdle

• Clavicles (2): collar bones

• ________(2): shoulder blades

• Acromion: extension of the scapula/high pt

Upper Extremities

• Humerus: ____________

• Radius: _____side of forearm

• ______: little finger side of forearm

• Olecranon process (funny bone)

WRISTS AND HANDS

• Carpals (8) = ______• Metacarpals (5) =

_______________• ______ (14) = fingers

– Distal

– Medial

– Proximal

PELVIC GIRDLE

• Os Coxae (2): contains the acetabulum (hip socket)

• 3 components: – _________ – upper blade of

the pelvic girdle

– Sacroiliac – slightly moveable articulation betw. sacrum and ilium

– Ischium – ______, posterior portion

• Also, contains the sacrum

LOWER EXTREMITIES

• Femur: ________• Patella: kneecap• Tibia: _________• Fibula: lateral bone of

lower leg

ANKLES AND FEET

Common Skeletal Bones