Shared Flashcard Set

Details

Bones
Histology of Bone
64
Other
Professional
08/19/2011

Additional Other Flashcards

 


 

Cards

Term
Describe osteoclasts
Definition
very large, multinucleated bone-reabsorbing cells
Term
Where are osteoclasts found?
Definition
In indentations of the bone matrix that they make called resorption bays or Howship's lacunae
Term
What is the name of the cell that breaks down calcified cartilage?
Definition
chondroclasts
Term
What is the name of the cell that breaks down dentin?
Definition
odontoclasts
Term
What is the main organic component in the matrix of the bone?  What does it do?
Definition
Collogen fibers, they help prevent breaking
Term
What inorganic component is known to give bones their hardness?
Definition
Calcium phosphate, also called Hydroyapatite
Term
This is known as a specialized connective tissue that contains cells and intercellular matrix
Definition
Bone
Term
What are the three types of tissue bone contains?
Definition
Bone connective tissue, nervous tissue and blood CT, and cartilage in articular region of long bones
Term
The humerus is what type of bone
Definition
long bone
Term
What type of bones make up the wrist
Definition
short bones
Term
What kind of bone is the sternum
Definition
flat bones
Term
What types of bones are the skull and veterbra?
Definition
irregular bones
Term
What type of bone is the patella (kneecap)?  These bones develop within tendons.
Definition
sesamoid bones
Term
What are the ends of long bones called?
Definition
epiphysis
Term
What are the two names for the surface along the inner core of a long bone?
Definition
medullary cavity and marrow cavity
Term

The shaft of a long bone is called the...

 

a) epiphysis

b)odontoblast

c) growth plate

d) diaphysis  

Definition
d) diaphyis
Term
What is the difference between the endosteum and the marrow cavity?
Definition
The endosteum is the inner surface and the marrow cavity is the 3D area
Term
The outer surface of a long bone is called the what?
Definition
periosteum
Term
What is the metaphysis?
Definition
the transition area between the epiphysis and diaphysis.  There is columns of spongy bone in this region
Term
[image]
Definition
epiphysis is the green portion
Term
Describe the lineage of cells that result in osteocytes.
Definition
Mesenchymal cells -> Osteoprogenitor cells -> Osteoblasts -> Osteocytes
Term
What is the function of osteoblasts?
Definition
build bone. They are involved in the mineralization of collogaen fibers and they synthesize and secrete organic bone matrix
Term
How do osteoblasts become osteoclasts?
Definition
as osteoblasts build the surrounding bone and become trapped in the bone, they differentiate into osteocytes
Term
What is the structure in the bone that osteocytes are housed in?
Definition
lacunae
Term
What are osteoclasts derived from?
Definition
hematopoietic stem cells -> macrophages -> osteoclasts
Term
After osteoclasts attach to a bone, what happens for the degradation of the bone to occur?
Definition
Osteoclasts attaches to "sealing zone" of bone matrix with ruffled border. Osteoclasts secrete HCL and protein digesting lysosomal enzymes from ruffled borders. Proteolytic enzymes stored in lysosomes of osteoclasts.
Term
What are the two architectural types of bone in adults?
Definition
Compact bone - dense outer layer, Spongy (cancellous) bone - internal network of bone.
Term
What is red marrow?
Definition
Marrow that produces bloods cells
Term
What is yellow marrow?
Definition
Marrow composed mostly of lipids and fats
Term
What anchors the periosteum to compact bone?
Definition
Transverse fibers known as Sharpey's Fibers
Term
Where is the periosteum not present?
Definition
Bone covered by articular cartilage, sesamoid bones found within tendons, and areas where tendons and muscle insert into bone.
Term
What is the network of the spongy bone called?
Definition
Trabeculae
Term
What is the tunnel running through the Osteon called?
Definition
Haversian Canal
Term
What connects separate Haversian Canals?
Definition
Volkmann's canal
Term
What are the concentric circles in the Haversian System called?
Definition
lamella
Term
How are osteocytes from different lamella connected?
Definition
Small tunnel-like structures called Canaliculus
Term
What forms enamel?
Definition
ameloblasts
Term
What forms dentin?
Definition
odontoblasts
Term
What are the symptoms of Acromegaly?
Definition
Increased bone formation in adults. Over production of somatotropin. Causes thickening of the bones, esp in the face.
Term
What is occuring during osteoporosis?
Definition
increased osteoclast activity in comparison to osteoblast activity
Term
Osteomalacia is an adult version of this disease and is caused by a lack of what?
Definition
Adult version of rickets, caused by deficiency of Vitamin D
Term
What is osteosarcoma
Definition
malignant bone cancer
Term
What occurs in Paget's disease?
Definition
Excessive bone breakdown and formation which causes dense but fagile bone.
Term
Which part of the bone has fibrous and cellular layers like its cartiladge counterpart?
Definition
periosteum
Term
Why doesn't the periosteum cover the epiphysis regions in some bones?
Definition
Because the epiphysis could be covered in cartilage
Term
What is another term for the growth plate?
Definition
epiphyseal plate
Term
What is an osteoid?
Definition
The organic components of bone matrix. Unmineralized and composed of proteoglycans, GAGs, glycoproteins, and collagen
Term
Which of the bone cells does not divide?
Definition
Osteocytes
Term
What do osteocytes do?
Definition
maintain protein and mineral content of matrix, help repair damaged bone,
Term
What is the space between the plasma membrane of an osteocyte and the wall of lacuna called? What is there?
Definition
This is the Periosteocytic space, filled with extracellular fuild rich in nutrients and exchageable Ca generated from bone during bone resorption by osteoclasts
Term
What does osteoclasts secrete when the are breaking bone?
Definition
HCL and lysosomal enzymes (Cathepsin K). HCL dissolves the inorganic matrix in the bone, Cathepsin K breaks down collagen and other matrix proteins
Term
Are osteoblasts enough for bone growth?
Definition
No, need a balance of osteoblasts and osteoclasts
Term
What are the main components of the bone matrix?
Definition
1/3 protein fibers (collagen type 1), 2/3 Calcium phosphate, and several glycoproteins.
Term
What glycoproteins are in the bone matrix?
Definition
osteocalcin, osteopontin, bone sialoproteins, and osteonectin
Term
What is hydroxyapatite?
Definition
crystals that form in the bone. Made of calcium phosphate.
Term
What is the main organic component of bone and dentine?
Definition
Type 1 collagen
Term
What is (are) the main organic component(s) of enamel?
Definition
amelogenins and enamelins (no collagen)
Term
What is the difference between primary and secondary bones?
Definition
Primary form during fetal development and are seconday bones are found in adults. Primary have a low mineral content while secondary are more calcified and are stronger.
Term
What does the endosteum face?
Definition
medullary or marrow cavity
Term
What does the endosteum consist of?
Definition
bone cells
Term
Haversian canals are lined with what kind of cells?
Definition
osteoprogenitors and osteoblasts. Both are invovled in bone rebuilding
Term
Where does the spongy bone originate from?
Definition
the endosteon
Term
What are other names for the spongy bone?
Definition
cancellous bone and trabecular bone
Term
What pathway do compact bone have than spongy bone don't have?
Definition
osteon
Supporting users have an ad free experience!