bone Flashcards
What is Tissues are bone comprised of?
bone connective tissue, dense irregular tissue, nerves
What is compact bone and it’s function?
forms dense, hard outer casting of all bones
function: Resists forces from weight and movement
what cells is compact bone comprised of?
Osteons
where is spongy bone present?
Found in flat bones and ends of long bones
What is spongy bone and its function?
it forms light, thin inner network of bone, lattice work of bone function: Resists stress on bones in multiple directions (like skin)
what kind of tissue does spongy bone house?
hematopoietic tissue
What is the function of the skeletal system?
Support, protection, mineral storage, hematopoiesis
Where does hematopoiesis occur?
red bone marrow in some spongy bone
where does hematopoiesis happen in children?
red bone marrow mostly in spongy bone
where does hematopoiesis happen in adults?
axial skeleton, proximal epiphyses of humerus and femur, marrow in shafts of long bones turns to yellow bone marrow.
Are osteocytes vascular or avascular?
Vascular
what are osteocytes?
mature bone cells that rest in the lacunae and are surrounded by the periosteum and its mineralized
What are chondrocytes?
mature cartilage cells embedded in lacunae of the matrix, semi solid ground substance
how is nutrients obtained in cartilage?
Diffusion of ground substance
What are chondrocytes surrounded by?
perichondrium (dense irregular tissue)
What is the function of hyaline cartilage and where is it?
Provides smooth surface for joint movement and support located in joint surfaces, trachea, and fetal skeleton
What is the function of fibrocartilage and where is it?
support and withstanding compression located in the intervertebral discs, pubic symphysis, and menisci
What are long bones and what is their function?
They are longer than they are wide function: Levers, joints, and pivots for body movement
what is the function of the elastic cartilage and where is it located?
flexibility and strength, and its in external ear
what are short bones and their function?
They are as long as they are wide(cube shaped)
function: Distribute and transfer forces across multiple bones
What are flat bones and their function?
Thin layer of spongy bone in between compact bone
function: broad surface for muscle attachment and provides protection
What are irregular bones and their function?
Irregular and varied shaped bones function: Attachment and protection
What is the diaphysis?
It is a cylindrical shaft that is compact bone (the middle part of the bone)
What is the medullary cavity and what does it consist of?
it is hollow inside of the diaphysis its lined with endosteum and has yellow bone marrow
what is the endosteum?
Dense irregular connective tissue around the medullary cavity
What is the epiphysis and what type of bone does if have?
The ends of bones and it has compact bone surrounding spongy Bone
What are the two types of epiphysis?
proximal epiphysis and distal epiphysis
What is articular cartilage and it’d function?
it is hyaline cartilage on the epiphyses
function: Reduces friction between connecting bone
what is osteoarthritis?
Its the break down of hyaline cartilage, can happen in young people with repetitive joint movement
What is the epiphyseal plate and its function?
hyaline plate between diaphysis and epiphysis
function: Length wise bone growth
What is the epiphyseal line?
The growth plate fully grown and seen in adults after puberty it is a thin plate of compact bone
What is the periosteum and its function?
dense irregular tissue that covers outside of bone
function: Growth in bone width
what are perforating fibers?
Protein fibers that anchor the periosteum to bone and are very vascular with lots of nerves
What are osteoblasts and their function?
Immature bone cells that create bone and secretes osteoid
What are osteocytes and their function?
mature bone cells that maintain the bone matrix
what are osteoclasts and its function?
Formed from red bone marrow ask they break down and resorb bone
which bone cell is not the same as the others and why?
the osteoclast because it has a different origin and cell line its similar to macrophages
what are osteons?
Cylindrical structures that run parallel to the length of the diaphysis
what is the central canal?
Opening that contains blood vessels and nerves with one periosteum
what is the concentric lamellae?
Concentric rings of bone matrix its the rings around the bullseye
What is the lacunae?
Spaces where osteocytes reside
what is the canaliculi?
tiny channels that radiate from lacunae and direct connections for waste and nutrients for bone
What bone is not in an osteon?
spongy bone
What is a perforating canal?
Canals that run perpendicular to the central canals it connects multiple canals together
What is the interstitial lamellae?
incomplete remnants of osteons, no central canals
what so the circumferential lamellae?
rings of bone that run the entire circumference of the shaft, its the longest word longest lamellae, created by the periosteum
What is ossification?
Formation and growth of bone tissue
what is intramembraneous of ossification?
preexisting tissue is mesenchyme and happens in flat bones
What is endochondral ossification?
Pre existing tissue is hyaline cartilage and happens in most of bones in the body
What is the order of bone growth?
- Fetal hyaline cartilage model of bone develops
- Primary ossification centers form in diaphysis
- Secondary ossification centers form in epiphyses
- Bone replaces cartilage except the articular cartilage and epiphyseal plate
- Epiphyseal plate ossify and form epiphyseal Line
When is the primary ossification center formed?
Starts at 12 weeks
when is the secondary ossification center formed?
At birth
What is the process of fracture repair?
- Fracture hematoma
- Fibrocartilage callus
- Bony callus
- Remodeling
what is a fracture hematoma
formed when a bone breaks blood clot
What is fibrocartilaginous callus?
Formed at site of the fracture soft cartilage
what is the bony callus?
this is when soft callus is replaced with bony callus
what happens when bone is remodeled?
newly repaired bone is remodeled to its original form
Where is red bone marrow in adults?
The proximal epiphysis of humerus
