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ANAPHY Lab ( 2nd reviewer mas mahaba and detailed)

ANAPHY Lab ( 2nd reviewer mas mahaba and detailed)

  • Components of Skeletal System

  • Bones

  • Cartilages

  • Tendons

  • Ligaments

  • Functions of the Skeletal System:

  1. Body support

  2. Organ protection

  3. Body movement

  4. Mineral storage

  5. Blood cell production

Bone Histology

  • Their characteristics are largely determined by the composition of their extracellular matrix.

  • The matrix always contain collagen, ground substance, and other organic molecules, as well as water and minerals.

  • Collagen - is a fibrous protein that provides flexibility but resists pulling or compression.

  • Proteoglycans - are water tapping proteins that help cartilage to be smooth and resilient.

  • Bone matrix is 35% organic & 65 % inorganic material by weight.

  • The organic material is primarily collagen and proteoglycans.

  • The inorganic material is primarily a calcium phosphate crystal called hydroxyapatite.

Bone Cells

  • Osteoblasts are responsible for the formation of bone and the repair and remodeling of bone.

  • Osteoblasts produce collagen and proteoglycans

  • The formation of new bone by osteoblasts is called ossification.

  • Osteocytes are cells that maintain bone matrix and form from osteoblast after bone matrix has surrounded it.

  • Osteocytes account for 90-95% of bone cells and are very long lived.

  • Osteocyte cell bodies are housed within the bone matrix in spaces called lacunae.

  • Their cell extensions are housed in narrow long spaces called canaliculi.

  • Osteoclasts are bone-destroying cells.

  • They contribute to bone repair and remodeling by removing existing bone, called bone reabsorption.

  • Lamellar bone - Mature bone; it is organized into thin, concentric sheets or layers, called lamellae.

  • Spongy bone - less bone matrix and more space.

  • Compact bone - more bone matrix and less space.

  • Spongy bone - consists of interconnecting rods or plates of bone called trabeculae.

  • Compact bone - is the solid outer layer surrounding each bone.

  • Osteon - the functional unit of compact bone; it is composed of concentric rings of matrix surrounding a central canal.

  • These are lined with endosteum and cond contains blood vessels, nerves, and loose connective tissue.

  • Lamellae - are concentric rings of bone matrix which surrounds the central canal.

  • Lacunae- where osteocytes are located in spaces between the lamellar rings.

  • STRUCTURE OF LONG BONE 1

  • Diaphysis- is the center portion of the bone which is composed of compact bone surrounding a hollow center called the medullary cavity.

  • Epiphyses- ends of a long bone.

  • STRUCTURE OF A LONG BONE 2

  • Articular cartilage - hyaline cartilage that covers the end of a long bone.

  • Epiphyseal plate - located between the epiphysis and the diaphysis.

  • Epiphyseal line - the ossification of the epiphyseal plate when the bone stops growing in length.

  • The average adult has 206 bones

  • Axial Skeleton - consists of the bones of the skull, the auditory ossicles, the hyoid bone, the vertebral column, and the thoracic cage.

  • Appendicular skeleton - consists of the upper limbs, the lower limbs,and the two girdles.

  • Girdle - refers to the 2 zones where the limbs are attached to the body. ( pectoral and pelvic girdle _

  • Long - upper and lower limb bones; bones are longer than they are wide

  • Short - wrist and ankle bones; are approximately as wide as they are long

  • Flat - skull and sternum; has a relatively thin, flattened shape.

  • Irregular bones - vertebrae & facial bones; have shapes that do not fit readily into the other 3 categories.

  • Skeletal Terminology 1

Foramen - hole

Fossa - depression

Process - projection

Condyle - smooth, rounded end

Meatus/canal - canal-like passageway

Tubercle/tuberosity - lump of bone

PROJECTIONS THAT ARE SITES OF MUSCLES AND LIGAMENT ATTACHMENT

Tuberosity = large rounded projection; may be roughened

Crest = Narrow ridge of bone; usually prominent

Trochanter - very large, blunt, irregularly shaped process (on femur)

Tubercle- small rounded projection/process

Epicondyle - raised area on/above a condyle

Spine - sharp, slender, often pointed projection

Process - Any bony prominence

PROJECTIONS THAT HELP FORM JOINTS

Head - bony expansion carried on a narrow neck

Facet - smooth, nearly flat articular surface

Condyle - Rounded articular projection

Ramus - Armlike bar of bone

DEPRESSIONS AND OPENINGS FOR PASSAGE OF BLOOD VESSELS AND NERVES

Groove - Furrow

Fissure - Round/oval opening through a bone

Notch - Indentation at the edge of a structure

OTHERS

Meatus - canal-like passage way

Sinus - bone cavity, filled with air and lined with mucous membrane

Fossa- shallow basinlike depression in a bone, often serving as an articular surface.

  • Axial skeleton - is composed of the skull, the vertebral column and the thoracic cage.

  • The skull has 22 bones

  • The bony structure of the face has 14 facial bones, and the braincase consists of 8 cranial bones. 13 of the facial bones are rather solidly connected to form the bulk of the face.

  • 3 auditory ossicles in each middle ear (6 in total)

Cranial structures

  • Sutures - immovable joints that connects the cranial bones.

4 principal sutures:

  • Coronal

  • Sagittal

  • Lamboid

  • Squamous

Cranial Bones

  • Frontal bone - anterior part of cranium, the ‘forehead’

  • Parietal bones - sides and roof of cranium.

  • Occipital bones - posterior portion and floor of cranium.

  • Temporal bones - inferior to parietal bones on each side of the cranium; Temporomandibular joint

  • Sphenoid bone - forms part of the cranium floor, lateral posterior portions of eye orbits, lateral portions of cranium anterior to temporal bones; Sella turcica

  • Ethmoid bone - anterior portion of cranium, including medial surface of eye orbit and roof of nasal cavity; Nasal conchae

Facial Bones

  • Maxillae - forms the upper jaw, anterior portion of hard palate, part of lateral walls of nasal cavity, floor of eye orbits; Maxillary sinus

  • Palatine bones - forms posterior portion of hard palate, lateral wall of nasal cavity.

Facial bones

  • Zygomatic bones - cheek bones; also forms floor and lateral wall of each eye orbit

  • Lacrimal bones - medial surfaces of eye orbits

  • Nasal bones - forms bridge of nose

  • Vomer - in midline of nasal cavity; forms nasal septum with the ethmoid bone

  • Inferior nasal conchae - Attached to lateral walls of nasal cavity

  • Mandible - lower jawbone; only movable skull bone

THE SKULL

Paranasal Sinuses - several bones that are associated with the nasal cavity and has large cavities within them.

These are :

  • Rontal

  • Ethmoid

  • Sphenoid

  • Maxillary

Hyoid bone - an unpaired U-shaped bone that is not part of the skull and has no direct bony attachment to the skull or any other bones; it is the only bone in the body that does not articulate with another bone

Vertebral Column - is the central axis of the skeleton, extending from the base of the skull to slightly past the end of the pelvis.

  • Consists o 26 individual bones, grouped into 5 regions

4 major curvatures :

  • Cervical region - curves anteriorly

  • Thoracic region - curves posteriorly

  • Lumbar region - curvers anteriorly

  • Sacral and coccygeal regions - together curve posteriorly

  • 7 cervical vertebra

  • 12 thoracic vertebra

  • 5 lumbar vertebra

  • 1 sacru

  • 1 coccyx

Atlas

  • 1st vertebra

  • Holds head

Axis

  • 2nd vertebra

  • Rotates head

Functions of Vertebral Column

  • Supports body weight

  • Protects the spinal cord

  • Allows spinal nerves to exit the spinal cord

  • Provides a site for muscle attachment

  • Provides movement of

Thoracic cage 1- protects the vital organs; 12 pairs of ribs

Sternum : breastbone

True ribs : attach directly to sternum by cartilage

False ribs : attach indirectly to sternum by cartilage

Floating ribs : not attached to sternum

Pectoral Girdle and Upper Limb

  • Scapula - shoulder blade

  • Clavicle - collar bone

  • Humerus - upper portion of forelimb

  • Ulna - forearm

  • Radius - forearm

  • Carpals - wrist

  • Metacarpals - hands

  • Phalanges - fingers

Pelvic Girdle - where lower limbs attach to the body

  • Pelvis - includes pelvic girdle and coccyx

  • Ischium - inferior and posterior region of hip bone

  • Ilium - most superior region of hip bone

  • Acetabulum - hip socket (joint) of hip bone

Lower Limb Bones:

  • Femur - thigh

  • Patella - knee cap

  • Tibia - Large bone of lower leg

  • Fibula - Smaller bone lower leg

  • Tarsals - ankle

  • Metatarsals- foot

  • Phalanges - toes and fingers

Articulations/ Joints

  • Are where 2 bones come together.

  • Classified as structurally fibrous, cartilaginous, or synovial according to the major connective tissue type that binds the bones together and whether a fluid-filled joint capsule is present.

  • Classified in functional categories according to their degree of motion as synarthroses, amphiarthrosis, diarthroses

Structural classification of joints:

  • Fibrous joint :

  • United by fibrous connective tissue; subclasses are sutures, syndesmosis & gomphoses

  • Cartilaginous :

  • United by means of cartilage; subclasses are synchondrosis & symphysis

  • Synovial

  • Joined by a fluid cavity; most joints of the appendicular skeleton

  • Surrounded by fluid filled fluid cavity; created by the joint capsule

  • The joint capsule consists of 2 layers:

  • An outer fibrous capsule

  • An inner synovial membrane

Functional Classification of Joints

  • Synarthosis:

  • Non-movable joint

  • Example - skull bone articulations

  • Amphiarthrosis

  • Slightly movable joint

  • Example - between vertebrae

  • Diarthrosis

  • Freely movable joint

  • Example - knee, elbow, and wrist articulations

TYPES OF MOVEMENT:

  • Flexion - bending

  • Extension- straightening

  • Abduction- movement away from midline

  • Adduction - movement toward the midline

  • Pronation- rotation of the forearm with palms up

  • Supination - rotation of the forearm with palms up

  • Rotation- movement of a structure about the long axis