Chapter 6 Flashcards
Skeletal System: Bones
what are four components for the skeletal system
bones, cartilage, tendons, and ligaments
what are the functions of the skeletal system?
framework for the body
protection
allow movement
store minerals in bone
stores adipose in bone cavity
red bone marrow- hematopoiesis
what do tendons attach
muscle to bones
what do ligaments hold
bone together
what are the three types of cartilage
hyaline, elastic, fibrocartilage
what cartilage is from embryonic skeleton and makes bone
it is often at the end of bones to help with glide vs friction
has a glassy background and collagen
hyaline
what type of cartilage has elastin, is flexible usually in external ear and epiglottis
elastic
what cartilage has collagen fibers and is strong
usually found in pubic symphysis, knee meniscus, and in intervertebral discs
fibrocartilage
what are two ways for cartilage growth
appositional and interstitial
name for cartilage forming cells that secrete new matrix against external face of existing cartilage
appositional
chondrocytes divide and secrete new matrix and expand cartilage from within
interstitial
reinforced concrete is called
bone matrix
flexible strength is
collagen
if collagen is lose than it is
brittle
name bone cells
osteoblasts, osteocytes, and osteoclasts
ossification bone types are
woven and lamellar bone
final bone types are
compact and spongy
what bone cell build matrix
osteoblasts
what lays down new bone on surface (appositional)
osteoblasts
what maintains matrix, 90-95% bone cells and arise from osteoblasts
osteocytes
what bone cell live long and up to 25 year
osteocytes
what bone cell is found in lacunae and communicate via canaliculi
osteocyte
what bone cell breakdown matrix (reabsorption)
osteoclasts
what brings calcium into the blood and arise in the red bone marrow
osteoclasts
where does ossification occur
as fetus, when we grow, and when we repair fracture
what is formed first by osteoblasts and are weak due to random placement of collagen
woven bones
woven is broken down by
osteoclasts
what is formed by osteoblasts to build stronger, more permanent bone
lamellar bone
what is arranged in concentric sheets/layers= lamellae
have a parallel arrangement= strong
lamellar bone
what appears porous, with more space
consists of trabeculae= interconnected rods
thin, found along mechanical stress lines
spongy bone
what has more bone matrix
dense, solid outer layer
osteon/haversian system=unit
concentric rings of lamellae
compact bone
main shaft of a long bone is called
diaphysis
what is composed of compact bone, medullary cavity in center
long bone
what is the ends, mostly spongy bone of a long bone called
epiphysis
what is covered in articular cartilage on a long bone
epiphysis
what growth is complete what is it called
epiphyseal line
red rise to blood cells in epiphyses
bone marrow
layers of a long bone
periosteum, endosteum, sharpey’s fiber
outer surface, dense irregulat ct
periosteum
inner surface, bone cells
endosteum
attachment, strengthen area for ligament/ tendon
sharpey’s fibers
other bone types include
flat, short and irregular
spongy bone sandwhich is
flat
no diaphysis, small growth plates
short and irregular
fetal ossification all derive from
mesenchymal ct
fetal ossification
intramembraneous and endochondral
what fetal ossification is at embryo at 8 weeks to 2y/o
intramembraneous
what fetal ossification is in embryonic CT (fibrous) and flat (cranium)
intramembraneous
hyaline cartilage and long is what fetal ossification
endochondral
whats at the base of skull, mandible area, clavicle epiphyses, rest of skeleton
endochondral
what fetal ossification is found in embryo at 8 weeks in some are and other areas start at 18-20 y/0
endochondral
3 steps for intramembraneous ossification
- osteoblast formation
- spongy bone formation
- compact bone formation
where does intramembraneous ossification begin
ossification centers
what is covered by membrane, bone fuse to cover. allows brain growth and complete about 22 months. anterior is largest
fontanels
in ossification centers what is the oldest and whats the youngest
center and edges
Mesenchymal cells- Osteochondral Progenitor Cells- Osteoblasts (Lay down Bone Matrix) & Become Osteocytes.
Trabeculae of Woven Bone develop.
osteoblast formation
Osteoblasts present on Trabeculae Surface, Cause it to become Larger and Longer.
Trabeculae join together to form Spongy Bone
spongy bone formation
Red bone marrow forms, as does Periosteum. Osteoblasts from Periosteum lay down bone matrix to form
Compact Bone.
Creates Bone with Outer compact bone & Spongy in Center. Spongy Sandwich.
compact bone formation
endochondral ossification
- cartilage model formation
- bone collar formation
- primary ossification center
- secondary ossification center
- adult bone
Mesenchymal cells Osteochondral Progenitor Cells Chondroblasts Chodrocytes
Hyaline Cartilage Model.
cartilage model formation
