A&P chapter 6
What else is found in bone matrix?
CaPO4 and CaCO4
What is articular cartilage?
a thin layer of hyaline cartilage that covers the epiphyses
Whats another name for a sutural bone?
a wormian bone
How do osteoclasts break down matrix?
acids and enzymes eat up the matrix
Whats an example of a long bone?
all the appendages
What bones are included in the appendicular skeletal?
all the bones of the upper and lower limbs and bones that form the girdles that connect those bones to the axial skeletal.
Where is interstitial lamellae found?
between osteons
What is hemopoiesis?
blood cell production
What does the central canal of the osteon contain?
blood vessels and nerves
How does the skeletal system support?
bone bears weight
What are osteoclasts?
bone cells that break down matrix
What do the bones of the skeletal system protect?
bone protects the organs that they surround
What does the skeletal system consist of?
bone, cartilage, ligaments and tendons
What are some examples of short bones?
bones in the wrists and ankles
How are osteoblasts connected to each other?
by gap junctions
What are two minerals that are stored in bone?
calcium and phosphorus
What provides a flexible cushioning for the bodys joints?
cartilage
What is the main organic substance in the bone matrix?
collagen
What are the two different types of bone tissue?
compact bone and spongy bone
Does compact bone have a good blood supply?Why?
compact bone has a good blood supply because the blood vessels and nerves in the central canal actually penetrate the matrix all the way through the bone
What is the arrangement of compact bone?
compact bone is arranged in tubular units called osteons
Short bones look roughly like what?
cubes
What is a single layer of bone forming cells and a little connective tissue that lines the internal cavities of bone?
endosteum
How does the skeletal system function in fat storage?
fat is stored in yellow marrow
What is circumferential lamellae?
flat plains of matrix
Whats another name for red marrow?
hemopoetic tissue
What is the epiphyseal plate made of?
hyaline cartilage
What is the primary chrystallized mineral salt found in the bone matrix?
hydroxyapatite
What do the ions and enzymes secreted by the osteoblasts form?
hydroxyapatite crystals
Where are blood cells produced?
in red marrow
Where is the marrow cavity found?
in spaces in the diaphyses
Where are osteogenic cells found?
in the periosteum, endosteum, and blood vessel canals
Where does a sutural bone form?
in the sutures of the skull, between the skull bones
The axial skeleton consists of the bones that lie around the ____ axis of the human body.
long
What are the six bone shapes?
long, short, flat, irregular, sesamoid,and sutural
What does bone consist of?
matrix and bone cells
What are osteogenic bone cells made from?
mesechyme
And what do the hydroxyapatite crystals do?
mineralize and and harden the matrix
What is the main function of the appendicular skeleton?
movement
Does an osteocyte secrete matrix?
no
Where is compact bone found?
on the external surface of all bones
What do osteoblasts secrete?
osteoblasts secrete Ca2+ ions and phosphate PO42- ions and enzymes
What do osteoblasts become?
osteocytes
What are the four types of bone cells?
osteogenic cells, osteoblasts, osteocytes, and osteoclasts
Its just an extra piece of bone for extra strength
...
Now lets talk about the structure of a bone
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Now, lets talk about bone histology
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now lets talk about bone cells
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now we're talking about bone tissue
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What is the main function of the axial skeleton?
protection
What are the two types of epiphyses?
proximal and distal
What does the marrow cavity contain?
red marrow or yellow marrow
Where is the metaphyses?
regions in mature bone where the diaphyses meets the epiphyses
What is interstitial lamellae?
remnants of old osteons that were partially removed during bone remodeling
Whats it called when the acids and enzymes eat up and break down the matrix?
resorption
Where are osteoclasts found?
stem cells in the red marrow
What are osteogenic bone cells?
stem cells that give rise to osteoblasts
What are the six functions of the skeletal syste?
support, protection, movement, mineral storage, fat storage and hemopoiesis
What are the two divisions of the skeletal system?
the axial skeleton and the appendicular skeleton
What is the diaphyses?
the body or shaft of the bone the long main part of the bone
Which part of the skeletal system stores minerals?
the bones
What are the seven main parts in a long bone?
the diaphyses, epihyses, metaphysis, epihyseal line, articular cartilage, periosteum, medullary, and endosteum
What does the metaphysis contain?
the epiphyseal plate or line
Whats another name for the marrow cavity?
the medullary cavity
Whats an example of a sesamoid bone?
the patella or kneecap
What is calcification?
the process by which mineral salts harden the matrix
What do osteoblasts produce?
the proteins that make up bone matrix
What are the epiphyses?
the rounded ends of the bones
What are the main bones of the axial skeleton?
the skull bones, ear bones, the hyoid bone, ribs, sternum and the vertebral bones
What are some examples of flat bones?
the sternum, the bones in the skull
Whats an example of an irregular bone?
the vertebra
What is a characteristic of a flat bone?
they are somewhat curved
How many different types of lamellae does compact bone have? What are they?
three; they are concentric lamellae, circumferential lamellae, and interstitial lamellae
How do bones cell communicate?
through canaliculi
What is an osteocytes main function?
to maintain the matrix
What is periosteum?
tough sheath of fibrous connective tissue that covers the bone surfaces not covered by articular cartilage
True or false. Calcification only occurs in the prescence of collagen.
true
How many types of bone tissue are there?
two
Where is it found?
under the periosteum; around the circumference of the bone; encircling the bone
What is the consistency of compact bone?
very dense with few spaces
What are the main inorganic substances in the bone matrix?
water and chrystallized mineral salts
How does the skeletal system produce movement?
when muscles contract
Long bones are longer than they are ____.
wide
What does a sesamoid bone form?
within a tendon
Where is concentric lamellae found?
within osteons
Are osteoclasts found in the endosteum?
yes
Are osteoclasts multinucleate?
yes
Are osteocytes mature bone cells that are completely surrounded by matrix?
yes
Are osteons aligned along lines of stress?
yes
Are osteons found within haversian systems?
yes
Can the alignment of osteons change throughout a persons life?
yes
Do osteogenic cells undergo division and produce osteoblasts?
yes
Does a kid have red marrow?
yes
Does an adult have mostly yellow marrow?
yes
So endosteum covers the marrow cavity?
yes
What fraction of the matrix is organic?
1/3
What fraction of the matrix is inorganic?
2/3
How many bone shapes are there?
6
How many main parts are there in a long bone?
7
What percent of the skeleton does compact bone make up?
80%
