Anatomy & Physiology Basic Skeletal Structures
Skeletal System 3.5: Bone Formation – Intramembranous Ossification
ICan2Ed, Inc.
The formation of bone during the fetal stage of
development occurs by two processes:
intramembranous ossification and endochondral
ossification. Formation of the flat bones of the skull,
the mandible, maxilla, and clavicles occurs for
intramembranous o_______.
Formation of the flat bones of the skull, the mandible,
maxilla, and clavicles occurs for i_________
o_______.
There are 4 steps in i_________ o________.
The first step in i_______ ossification is the
development of the ossification center.
The site where bone begins to form as a result of the
accumulation of osteoblasts in the connective tissue is
called the o________ c______.
Step 1 in i_______ ossification is the development of
the o________ c_______.
1
Step 2 in intramembranous ossification is calcification.
The process of laying down new bone material by cells
called osteoblasts is called c________.
In the second step of i__________o_________, new
bone replaces connective tissue in a process called
c_______.
Replacing c_______ tissue with new bone is called
c_______.
Step 2 in i_______ ossification is the c________ of
connective tissue with new bone cells.
There are 4 steps in i_________ o________.
R
Replacing c_______ tissue with new bone is called
c_______.
R
Step 1 in i_______ ossification is the development of
the o________ c_______.
2
The site where bone begins to form as a result of the
accumulation of osteoblasts in the connective tissue is
called the o________ c______.
Step 2 in i_______ ossification is the c________ of
connective tissue with new bone cells.
Step 3 in intramembranous o________ is the formation
of trabeculae. Spear-like projections, called spicules,
that form spongy bone are called the t______.
Osteoblasts lay down new bone along the t_______,
producing a lace-like structure that is known as spongy
bone.
As s______ of t_______ undergo calcification,
cancellous (spongy) bone is produced.
The fine spicules forming a network in cancellous bone
are known as the t_______.
In step 3, s______ of t_______ undergo calcification,
producing c_______ (spongy) bone.
3
There are 4 steps in i_________ o________.
Replacing c_______ tissue with new bone is called
c_______.
Step 1 in i_______ ossification is the development of
the o________ c_______.
As s______ of t_______ undergo calcification,
cancellous (spongy) bone is produced.
The site where bone begins to form as a result of the
accumulation of osteoblasts in the connective tissue is
called the o________ c______.
Step 2 in i_______ ossification is the c________ of
connective tissue with new bone cells.
In step 3, s______ of t_______ undergo calcification,
producing c_______ (spongy) bone.
4
As s______ of t_______ undergo calcification,
cancellous (spongy) bone is produced.
Step 4 in the intramembranous ossification is the
development of periosteum. The p______ is a
membrane that lines the outer surface of all bones,
except at the joints of long bones.
Periosteum is divided into an outer "fibrous layer" and
inner "cambium layer". The f______ layer contains
fibroblasts, while the c______ layer contains
progenitor cells that develop into osteoblasts.
Periosteum is attached to bone by strong collagenous
fibers called Sharpey's fibres. S______ f_____ are
also used to attach muscle to the periosteum of bone by
merging with the fibrous periosteum and underlying
bone.
In step 4 is the development of periosteum, a
membrane with a f______ layer, a c______ layer, and
S_______ f_____, which attaches muscles to bones.
There are 4 steps in i_________ o________.
5
Replacing c_______ tissue with new bone is called
c_______.
Step 1 in i_______ ossification is the development of
the o________ c_______.
The site where bone begins to form as a result of the
accumulation of osteoblasts in the connective tissue is
called the o________ c______.
Step 2 in i_______ ossification is the c________ of
connective tissue with new bone cells.
R
In step 3, s______ of t_______ undergo calcification,
producing c_______ (spongy) bone.
R
As s______ of t_______ undergo calcification,
cancellous (spongy) bone is produced.
In step 4 is the development of periosteum, a
membrane with a f______ layer, a c______ layer, and
S_______ f_____, which attaches muscles to bones.
Periosteum is divided into an outer f_____ layer and
inner c_____ layer.
6
There are 4 steps in i_________ o________.
Review
Replacing c_______ tissue with new bone is called
c_______.
Step 1 in i_______ ossification is the development of
the o________ c_______.
The site where bone begins to form as a result of the
accumulation of osteoblasts in the connective tissue is
called the o________ c______.
In step 3, s______ of t_______ undergo calcification,
producing c_______ (spongy) bone.
As s______ of t_______ undergo calcification,
cancellous (spongy) bone is produced.
In step 4 is the development of periosteum, a
membrane with a f______ layer, a c______ layer, and
S_______ f_____, which attaches muscles to bones.
Periosteum is divided into an outer f______ layer and
inner c_____ layer
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