Lecture 7 and 8 Flashcards
Function of hyaline cartilage
Provides some cushioning and minimising friction between where the bone ends
Function of fibrocartilage
Acts as a shock absorber and contribute to the durability found in intervertebral discs.
Function of elastic cartilage
Provides suppourt with moderate elasticity to parts of the body such as the ears
Where is hyaline cartialge found
. Found in fetal skeleton
. At ends of bones that articulate with each other
. Trachea, larynx and nose
Where is fibrocartilage found
intervertebral disc
pubic symphysis
menisci of the knee
Where is elastic cartilage found
epiglottis
external ear
What are the functions of bone
Support and protection
Movement
Hemopoiesis
Storage of mineral and energy reserves
Describe long bones
Greater length than width
Describe short bones
Nearly equal length and width
Describe flat bones
Thin surfaces
Describe irregular bones
Complex shapes
Describe the structure of long bone
Diaphysis
Epiphysis
Metaphysis
Describe diaphysis
Elongated, cylindrical shaft
Describe epiphysis
- Knobby, enlarged regions at each end
- Strengthens joints
- Attachment site for tendons and ligaments
Describe metaphysis
- Region between diaphysis and epiphysis
* Contains epiphyseal (growth) plate
Describe articular cartilage
Thin layer of hyaline cartilage covering the epiphysis
Function of articular cartilage
• Reduces friction and absorbs shock in moveable joints
Describe Medullary cavity
- Hollow, cylindrical space in diaphysis
* In adults, it contains yellow bone marrow
Describe endosteum
. Covers most internal surfaces of bones
• Contains osteoprogenitor cells, osteoblasts, and osteoclasts
Describe periosteum
• Covers external surfaces of bones (except articular cartilage)
Anchored by perforating fibres embedded in the bone matrix
Name the 4 bone cell types
Osteoprogenitor cells
Osteoblasts
Osteocytes
Osteoclasts
Describe Osteoprogenitor cells
stem cells derived from embryonic tissue (mesenchyme) found in endosteum and periosteum; can produce more stem cells or osteoblasts
Describe Osteoblasts
secrete bone matrix (osteoid); cuboidal in shape; once trapped in the matrix it becomes osteocytes - builds bone
Describe Osteocytes
mature bone cells that reside within lacunae; maintain matrix and detect mechanical stress on a bone
Describe Osteoclasts
Large, multinuclear cells, derived from bone marrow cells; dissolves bone matrix -
removes bone & releases calcium
Describe compact bone
. dense or cortical bone
• Solid and relatively dense
• External surfaces of long and flat bones
Describe spongy bone
cancellous or trabecular bone
• Open lattice of narrow plates called trabeculae (beams)
• Internal surface of bones
• Porous
Describe endochondral ossification
• The foetal hyaline cartilage model develops
Cartilage calcifies, and a periosteal bone collar forms
The primary ossification centre forms in the diaphysis
Secondary ossification centre form in the epiphyses
Bone replaces cartilage, except the articular cartilage and
epiphyseal plates
Epiphyseal plates ossify and form epiphyseal lines
Describe intramembranous ossification
Mesenchymal cells differentiate into osteoblasts and group into ossification centers
Osteoblasts become entrapped by the osteoid they secrete, transforming them to osteocytes
Trabecular bone and periosteum form
Cortical bone forms superficially to the trabecular bone
Blood vessels form the red marrow
Where does endochondral ossification occur
Carpal and Tarsal bones
Where does intramembranous ossification occur
Bones of the skull
What are the functions of the skeleton
. Supporting your body and helping you move . Protecting your internal organs . Producing your blood cells . Storing and releasing fat . Storing and releasing minerals
What are the subdivisions of the skeleton
Axial skeleton
Appendicular skeleton
What is the axial skeleton made up of
Skull, vertebral column, and thoracic cage
What is the appendicular skeleton made up of
Shoulder and hip bones and those of the upper and lower extremities
Describe cranial bones
8 bones that form the cranium and have direct contact with the brain
Describe facial bones
Includes 13 bones that form the face and have no brain contact
List the cranial bones
unpaired ethmoid, frontal, occipital, and sphenoid bones
paired parietal and temporal bones
List the facial bones
paired maxillae, nasal, lacrimal, zygomatic, palatine bones, inferior nasal conchae
unpaired vomer
What is the vertebral column made up of
Cervical vertebrae Thoracic vertebrae Lumbar vertebrae Sacrum Coccyx
Describe cervical vertebrae how many bones
7
Seven bones that form the neck
Describe Thoracic vertebrae how many bones
12
Twelve bones that form the superior regions of the back
Describe Lumbar vertebrae how many bones
5
Five bones that form the inferior concave region of the back
Describe Sacrum
how many bones
5 fused
Five fused vertebrae
Describe Coccyx
how many bones
3-5 fused
Four fused vertebrae
Describe pectoral girdle
Articulates with the trunk and
supports the upper limbs
What does the pectoral girdle consist of
Clavicle
Scapula
Describe pelvic girdle
articulates with the sacrum and
supports the lower limbs
What does the pelvic girdle consist of
os coxae (hip bones)
Describe os coxae
Fusion of ilium, ischium, and pubis between 13 and 15 years of age
What are the articulations of the os coxae
- Anteriorly with other os coxae
- Posteriorly with the sacrum
- Laterally with femur at acetabulum
- All three bones of os coxa contribute to its acetabulum
What does the pelvic limbs consist of
illium pubis ischium femur tibia fibula tarsal bones metatarsal bones phalanges
Compare and contrast female and male pelvis
• Female ilia laterally flared = wider pelvis
• Female pelvic inlet = wide oval; male’s = heart-shaped
• Female subpubic angle is wider: Greater than 100º compared to less than
90º in male
Features of scapula
Broad, flat triangle
Glenoid cavity articulates with head of humerus
Features of illium
Superior portion of os coxa
and acetabulum
Iliac fossa
Iliac crest
Greater sciatic notch
• Auricular surface
Describe illiac fossa
Large depression on
medial surface
Describe illiac crest
Superior ridge
Describe greater sciatic notch
For sciatic
nerve entering lower limb
Describe auricular surface
Medial
articulation with sacrum
Features of pubis
Subpubic angle
• Obturator foramen: Large hole
Anterior region of os coxae
What are the protective cavities within the skeleton
Cranial cavity Vertebral cavity Thoracic cavity Pelvic Cavity Abdominal cavity
