6.4-6.7 bone development Flashcards
bone formation in the fetus follows two processes
intramebranous ossification and endochondral ossification
soft spots that are the larger, membrane-covered spaces between the developing skull bones that have not yet been ossified
fontanels
bone formation that occurs within connective tissue membranes
intramembranous ossification
bone formation inside hyaline cartilage
endochondral ossification
two type of bone formation that result in compact and spongy bone
intramembranous and endochondral ossification
pads and cushions areas between and around bone
cartilage
bones greater in length than width
long bones
somewhat cube-shape bones, nearly equal in length and width
short bones
are broad, and relatively thin bones
flat bones
bones that are complex in shape
irregular bones
What occurs primarily in the skull when osteoblasts begin to produce bone with connective tissue known as mesenchyme
intramembranous ossification
bone formation within a hyaline cartilage model
endochondral bone
bone formation in the diaphysis of a long bon
primary ossification center
bone formation in the epiphysis
secondary ossification center
5 steps in endochondral ossification
- cartilage model formation
- bone collar formation
- primary ossification center formation
- secondary ossification center formation
- adult bone
4 steps in intramembranous ossification
- development of ossification center
- calcification
- formation of trabeculae
- development of the periosteum
in bone growth, the number of ______ increase on the epiphyseal aide of the epiphyseal plate
chondrocytes
dying chondrocytes are replaced by
osteoblasts
dust bones shoe evidence of the epiphyseal ____
line
bone growth in WIDTH by depositing new matrix between the periosteum and the existing matrix
appositional growth
what are four things required for bone growth
Mineral supply
Vitamin D3
Vitamins A,B,C,D,K
Hormones
deficiency of vitamin D3 that leads to softening bones (2 different names for adults and children)
adults- osteomalacia
children- rickets
hormones needed for bone growth
growth, thyroid, sex, parathyroid hormone
and calcitonin
bone remodeling involves removal of existing bone by ______ and deposition of new bone by _____
osteoclasts, osteoblasts
Boones are remodeled in response to what 2 factors
free calcium ion levels in the blood and the pull of gravity and muscles on the skeleton
bone is a major storage site for
calcium
calcium moves ____ bone as ______ build new bone
into, osteoblasts
calcium moves _____ of bone as ____ break down bone
out, osteoclasts
calcium homeostasis is maintained by
parathyroid hormone (PTH) and calcitonin
what hormone secretes the parathyroid gland and increase formation and a activation of osteoclasts
parathyroid hormone (PTH)
a crack or break in a bone
fracture
aka simple fractures, completely internal (no breaks in the skin) and can be seen only on x-rays
closed fractures
aka compound fractures, project thru the skin, more dangerous due to risk of infection
open fractures
been that becomes old is replaced with new bone in a process called
bone remodeling
long bones increase in length because of growth at the
epiphyseal plate
in a long bone, the epiphyseal plate separates the ____ from the ____
epiphysis, diaphysis
long bones form by creating new ____ in the epiphyseal plate
cartilage
four major steps of bone repair
- hematoma formation
- callus formation
- callus ossification
- bone remodeling
if the soft tissues around a closed fracture are damages, it is called a
complicated fracture
fracture that does not extend completely across the bone
incomplete fracture
the bone is broken into at least two fragments
complete fracture
localized mass of blood released from blood vessels but confined within an organ or space
hematoma
a mass of bone tissue that forms at a fracture site
callus
