Ch. 5: Bone Flashcards
bone is another type of specialized ct which is _______ and less _______ than cartilage
harder; flexible
structural support, serve as levers for muscles/locomotion, protect organs and house bone marrow, and metabolic reserve for minerals are all functions of what
bone
the matrix of bone is composed of ______ and _______
inorganic and organic matrix
65% of dry weight comes from what
inorganic matrix of bone
hydroxyapatite crystals, calcium phosphate, and other minerals compose what
inorganic matrix of bone
35% of dry weight comes from what
organic matrix of bone
what type of collagen is found in the organic matrix of bone
primarily collagen I
collagen I makes up what percentage of organic matrix
80-90%
what type of matrix has a highly organized fiber arrangement
organic matrix
what type of sulfated GAG’s are found in the matrix of bone
primarily chondroitin and keratin sulfates
what type of nonsulfated GAG is found in the matrix of bone
hyaluronic acid
hyaluronic acid in bone holds 20-25% of what
water
proteins that bind minerals to collagen (binding proteins), enhance mineral deposition onto collagen I, proteins that bind matrix components to cells, and are found in the matrix of bone are called what
glycoproteins
there is a higher percentage of organic matrix in who
adults vs. young children
as maturity increases matrix uniformity will _________ therefore stability ________
increases; increase
what types of cells are found in bone
osteoprogenitor (osteogenic cell), osteoblast, osteocyte, bone-lining cells, osteoclast
what type of cell appears flat, located in the endosteum and periosteum, usually derived from mesenchyme cells but possibly chondrogenic cells, functions to change into osteoblasts and undergoes mitosis
osteoprogenitor (osteogenic cell)
what type of cell appears cuboid to columnar, located in the endosteum and periosteum, derived from osteoprogenitor cells, functions to produce osteoids, and does not undergo mitosis
osteoblast
what cell produces materials (matrix vesicles) which initiates the calcification of the newly produced bony matrix
osteoblasts
osteoblasts respond to ________ directly
PTH (parathyroid hormones)
when an osteoblast responds to PTH it produces a factor _______ that causes creation of new osteoclasts
OPG
after an osteoblast produces factor OPG it secretes ________ _________ _________
osteoclast stimulating factor
after an osteoblast produces osteoclast stimulating factor it produces enzymes to condition bone for the ________
osteoclasts
what cell type appears to conform to the lacuna, surrounded by matrix, derived from osteoblasts and functions to maintain the matrix and monitor the matrix and does not undergo mitosis
osteocyte
what cell releases factors to influence osteoblast activities
osteocyte
what cell releases factors to cause creation of new osteoclasts
osteocyte
what cell appears flat, located primarily in the endosteum, usually derived from osteoblasts and possibly osteocytes, function to wait to become a osteoblast again and do not undergo mitosis
bone-lining cell
what type of cell is large and multinucleated, located in the endosteum and periosteum, derived from pre-osteoclasts and function to resorb bone
osteoclast
the mechanism of bone resorption occurs in the _______________ compartment
subosteoclastic compartment
the mechanism of bone resorption dissolves inorganics by using what
strong acids (primarily carbonic acid)
by using strong acids to dissolve inorganics during bone resorption pH __________
decreases
during bone resorption organics are borken down using what
lysosomal enzymes (occurs fast)
during primary hormone regulation of osteoclasts what will increase osteoclast activity by causing osteoblasts to secrete osteoclasts
PTH
during primary hormone regulation of osteoclasts what decreases osteoclast activity
calcitonin
primary bone is _________ bone or ________
immature bone or woven
secondary bone is ________ bone or _________
mature bone or lamellar
what type of bone is found in fetal development and bone repair
primary bone aka immature bone aka woven
what type of bone has many osteocytes, low minerals and more random collagen I
primary bone aka immature bone aka woven
what type of bone has more mineral therefore stronger bone
secondary bone aka mature bone aka lamellar
what type of bone has organized collagen I
secondary bone aka mature bone aka lamellar