Module 23 - Bone Tissue Flashcards
List the 5 functions of the skeletal system
support, protection, movement, storage, blood cell production
how does the skeletal system provide support
through bones, cartilage and ligaments
Bone is ___ while cartilage is ___
bone is hard while cartilage is flexible
ligaments are bone to ___
bone to bone
how does the skeletal system provide protection?
Skull around brain; ribs, sternum, vertebrae protect organs of thoracic cavity
how does the skeletal system provide movement?
Produced by muscles on bones, via tendons
how does the skeletal system provide storage?
Ca and P. Stored then released as needed. Fat stored in marrow cavities.
Ca: nervous system functions, muscle contractions…
P: ATP, metabolism…
Differentiate the different bone marrows
yellow: adipose tissue
red: produces different cell types
true or false
cartilage is:
firm
smooth
resilient
vascular
true
true
true
false, its avascular
what gives cartilage its resistance
Cartilage cells & matrix (70-85% water, protein, ground substance)
Give and describe the 3 types of cartilage
hyaline: most abundant
elastic: most flexible
fibrocartilage: strongest
The main cell type of cartilage is…? where is it located?
chondrocyte, immature = chondroblast
located in a cavity, lacuna
what is the perichondrium?
double layer of CT that covers most cartilage – nerve and blood supply
what is articular cartilage
no perichondrium
what is appositional growth
chondroblasts on surface grow
what is interstitial growth
mature chondroblast grow
What is the one huge difference between bone and cartilage that has to do with matrix
bone is constantly broken down and rebuilt, cartilage isn’t
Give the ratios of bone matrix structure
65% inorganic – crystallized mineral salts
35% organic – collagen/proteoglycans, water
what is hydroxyapatite
hydroxyapatite: calcium phosphate crystals (gets added to matrix for solidification)
why do we need both organic and inorganic components in bone matrix
collagen/proteoglycans – flexible strength
mineral component – compressive (weight-bearing) strength
without minerals the bone is…
extremely flexible
without collagen the bone is…
brittle
what do osteoblasts produce
Produce collagen and proteoglycans (vesicles)
what do osteoblasts form? what is this responsible for?
Form matrix vesicles of Ca 2+ and PO43- hydroxyapatite. Responsible for ossification.
what are Osteochondral progenitor cells? Describe their development.
Osteochondral progenitor cells: stem cells that can become osteoblasts or chondroblasts
what is an osteocyte? where is it located?
osteocyte = osteoblast surrounded by bone matrix.Also located in a cavity - lacuna
what is the role of osteocytes in the bones?
Considered inactive
Maintain ability to produce components necessary to maintain bone matrix
what are osteoclasts
Large multi-nuclear cells
Formed from fusion of monocytes
explain the function of osteoclasts
Resorption of bone
Acid & enzymes dissolve calcium, phosphorus and collagen
Fragments are engulfed and digested
This process is used to release what’s stored in the bones like Ca.
