Unit 1.4 Flashcards
Types of bones
Long, short, flat, irregular, sesamoid, sutural
Long bone
Example
Similar to columnar cells because the length exceeds the width
Femur- thigh bone, metatarsals too even though they are super small
Short bone
Example
Similar to cuboidal cells because the length is equal to the width
Tarsal- bone of the ankle
Flat bone
Example
Similiar to the squamous cells because the structure is compressed in one plane
Frontal- bone of the skull
Irregular bone
Example
No similar cell because the shape has characteristics of two or more types of bone
Vertebra
Sesamoid bone
Example
Is similar to cuboidal cells but is not classified as a short bone because this type of bone is found in a muscle tendons
Patella/ knee cap
Sutural bone
Is similar to a squats cell but is not classified as a flat bone because this bone is an island within the sutures of the cranial vault
Anatomy of a long bone
External surface- periosteum contains outer fibrous and inner cellular layers
Collagen fibers of the periosteum are continuous with those of the bone, adjacent joint, capsules, and attached tendons and ligaments
Bone Tissue- composed of compact of spongy bone
(Compact- consists of lamellae sheets of osteons (functional unit of bone) with osteocytes nested in lacunae)
(Spongy- consists of lattice framework of osteocytes and calcium salts and contains red bone marrow)
Internal Surface- endosteum is an incomplete layer cellular layers Collagen fibers lining the internal surface (marrow cavity) of long bones. Contains epithelial cells, osteoblasts, osteoprogenitor cells, and osteoclasts.
Which cell is responsible for the endosteum being an incomplete cellular area?
Osteoclasts- bone destroying cells
Regions of a long bones
Articular cartilage, epiphysis, epihyseal plate, metaphysis, diaphysis.
Articular Cartilage
Found
Hyaline cartilage that covers the articular surface (where one bone touches another) of bones
Found on the proximal and distal ends of long bones
Found on bone surfaces within joints
Epiphysis
Known
Composed
Contains
Upon the physis
The proximal most and distal portions of a bone
The region also known as the secondary ossification center
Composed of spongy bone with a thin layer of dense bone externally
Internally the Ephesus contains red bone marrow
Epiphyseal Plate
Found
Known
Cells
Found distal/inferior to the epiphysis
Known as growth plate
It is hyaline cartilage
The cells (chondrocytes) in this region transform themselves into osteoblasts, then osteocytes
The plate becomes the epiphyseal line when the cartilage has been fully replaced by bone - fusion (age of suasion is different between sexes)
Metaphysis
After growth
The region of bone inferior to the epiphyseal plate/growth plate and superior to the diaphysis or medullary cavity/bone marrow
It is spongy/cancellous/trabecular bone
Diaphysis
Cavity
Between growth
The central portion of a bone, shaft
It is dense or lamellar bone that grows in the diameter through ossification at the periosteum
The marrow cavity os the hollow internal area of the diaphysis/shaft
When young the marrow cavity contains red marrow that active in the production of all blood cells. Red marrow is replaced by yellow marrow as we age. Yellow marrow serves as a metabolite
Endochrondral ossification
Centers
Elongation
Responsible
Inside cartilage
Occurs in hyaline cartilage
Primary ossification center- diaphysis
Secondary ossification center- epiphysis
Continued elongation of long bones occurs at the epiphyseal plates
Responsible for the formation of most bones in the body
Intramembranous Ossification
Between cellular membrane
Is fibrous connective tissue of mesenchymal origin
Responsible for formation of skull, mandible, clavicle
During embryonic development and in early life there are fontanelles between flat bones of the skull
