BIOL235 MIDTERM EXAM 1 STUDY GUIDE
bone -(ANSWER)organ made up of several different tissues working together (bone
tissue, cartilage, dense connective tissue, epithelium, adipose tissue, nervous tissue)
skeletal system -(ANSWER)entire framework of bones and their cartilages
basic functions of skeletal system -(ANSWER)support [soft tissues, attachment of
tendons]
protect [important internal organs from injury]
assistance in movement
mineral homeostasis [storage and release]
blood cell production [red bone marrow]
triglyceride storage [yellow bone marrow]
long bone -(ANSWER)has greater length than width
diaphysis -(ANSWER)is the bone's shaft or body—the long, cylindrical, main portion of
the bone
epiphyses -(ANSWER)the proximal and distal ends of the bone
metaphyses -(ANSWER)the regions between the diaphysis and the epi- physes. In a
growing bone, each metaphysis contains an epiphyseal (growth) plate, a layer of
hyaline cartilage that allows the diaphysis of the bone to grow in length
epiphyseal line -(ANSWER)the cartilage in the epiphyseal plate is replaced by bone; the
resulting bony structure is known as the ______
articular cartilage -(ANSWER)thin layer of hyaline cartilage covering the part of the
epiphysis where the bone forms an articulation ( joint) with another bone. Articular
cartilage reduces friction and absorbs shock at freely movable joints.
periosteum -(ANSWER)tough connective tissue sheath and its associated blood supply
that surrounds the bone surface wherever it is not covered by articular cartilage. It is
composed of an outer fibrous layer of dense irregular connective tissue and an inner
osteogenic layer that consists of cells
medullary cavity (aka marrow cavity) -(ANSWER)hollow, cylindrical space within the
diaphysis that contains fatty yellow bone marrow and numerous blood vessels in adults.
This cavity minimizes the weight of the bone by reducing the dense bony material where
it is least needed
,BIOL235 MIDTERM EXAM 1 STUDY GUIDE
osteoprogenitor cells -(ANSWER)unspecialized bone stem cells derived from
mesenchyme, the tissue from which almost all connective tissues are formed. They are
the only bone cells to undergo cell division; the resulting cells develop into osteoblasts.
Osteoprogenitor cells are found along the inner portion of the periosteum, in the
endosteum, and in the canals within bone that contain blood vessels
osteoblasts -(ANSWER)bone-building cells. They synthesize and secrete collagen
fibers and other organic components needed to build the extracellular matrix of bone
tissue, and they initiate calcification
osteocytes -(ANSWER)mature bone cells, are the main cells in bone tissue and
maintain its daily metabolism, such as the exchange of nutrients and wastes with the
blood. Like osteoblasts, osteocytes do not undergo cell division
osteoclasts -(ANSWER)huge cells derived from the fusion of as many as 50 monocytes
(a type of white blood cell) and are concentrated in the endosteum. On the side of the
cell that faces the bone surface, the osteoclast's plasma membrane is deeply folded into
a ruffled border. Here the cell releases powerful lys- osomal enzymes and acids that
digest the protein and mineral com- ponents of the underlying extracellular bone matrix
compact bone tissue -(ANSWER)the strongest form of bone tissue. It is found beneath
the periosteum of all bones and makes up the bulk of the diaphyses of long bones.
Com- pact bone tissue provides protection and support and resists the stresses
produced by weight and movement.
80% of skeleton
osteons/haversian systems -(ANSWER)repeating strucutural units in compact bone
tissue. Each osteon consists of concentric lamellae arranged around an osteonic
(haversian or central) canal
concentric lamellae -(ANSWER)circular plates of mineralized extracellular matrix of
increasing diameter, surrounding a small network of blood vessels and nerves located
in the central canal
resemble growth rings of trees
lacunae (plural) -(ANSWER)small spaces between concentric lamellae containing
osteocytes
, BIOL235 MIDTERM EXAM 1 STUDY GUIDE
canaliculi -(ANSWER)small channels radiating out from lacunae, contain extracellular
fluid, connect lacunae with one another
interstitial lamellae -(ANSWER)areas between neighboring osteons, also have lacunae
with os- teocytes and canaliculi. Interstitial lamellae are fragments of older osteons that
have been partially destroyed during bone rebuilding or growth
interosteonic (Volkmann's/perforating) canals -(ANSWER)canals that penetrate
compact bone as patways fo blood vessels and nerves from periosteum
circumferential lamellae -(ANSWER)lamellae arranged around entire inner and outer
circumference of the shaft of long bones, develop during initial bone formation
perforating (aka Sharpey's) fibers -(ANSWER)connect external circumferential lamellae
to the periosteum
spongy bone tissue (aka trabecular/cancellous bone tissue) -(ANSWER)always located
in the interior of a bone, protected by a covering of compact bone, does not contain
osteons. Spongy bone tissue makes up most of the interior bone tissue of short, flat,
sesamoid, and irregularly shaped bones
trabeculae -(ANSWER)lamellae that are arranged in an irregular pattern of thin columns
periosteal arteries -(ANSWER)small arteries accompanied by nerves, enter the
diaphysis through many interosteonic (Volkmann's or perforating) canals and supply the
periosteum and outer part of the compact bone
nutrient artery -(ANSWER)passes through hole in compact bone called nutrient
foramen, found near the center of the diaphysis
metaphyseal arteries -(ANSWER)enter the metaphyses of a long bone and, together
with the nutrient artery, supply the red bone marrow and bone tissue of the metaphyses
epiphyseal arteries -(ANSWER)enter the epiphyses of a long bone and supply the red
bone marrow and bone tissue of the epiphyses
nutrient veins -(ANSWER)accompany the nutrient artery and exit through the diaphysis
epiphyseal veins + metaphyseal veins -(ANSWER)accompany their respective arteries
and exit through the epiphyses and metaphyses, respectively
bone -(ANSWER)organ made up of several different tissues working together (bone
tissue, cartilage, dense connective tissue, epithelium, adipose tissue, nervous tissue)
skeletal system -(ANSWER)entire framework of bones and their cartilages
basic functions of skeletal system -(ANSWER)support [soft tissues, attachment of
tendons]
protect [important internal organs from injury]
assistance in movement
mineral homeostasis [storage and release]
blood cell production [red bone marrow]
triglyceride storage [yellow bone marrow]
long bone -(ANSWER)has greater length than width
diaphysis -(ANSWER)is the bone's shaft or body—the long, cylindrical, main portion of
the bone
epiphyses -(ANSWER)the proximal and distal ends of the bone
metaphyses -(ANSWER)the regions between the diaphysis and the epi- physes. In a
growing bone, each metaphysis contains an epiphyseal (growth) plate, a layer of
hyaline cartilage that allows the diaphysis of the bone to grow in length
epiphyseal line -(ANSWER)the cartilage in the epiphyseal plate is replaced by bone; the
resulting bony structure is known as the ______
articular cartilage -(ANSWER)thin layer of hyaline cartilage covering the part of the
epiphysis where the bone forms an articulation ( joint) with another bone. Articular
cartilage reduces friction and absorbs shock at freely movable joints.
periosteum -(ANSWER)tough connective tissue sheath and its associated blood supply
that surrounds the bone surface wherever it is not covered by articular cartilage. It is
composed of an outer fibrous layer of dense irregular connective tissue and an inner
osteogenic layer that consists of cells
medullary cavity (aka marrow cavity) -(ANSWER)hollow, cylindrical space within the
diaphysis that contains fatty yellow bone marrow and numerous blood vessels in adults.
This cavity minimizes the weight of the bone by reducing the dense bony material where
it is least needed
,BIOL235 MIDTERM EXAM 1 STUDY GUIDE
osteoprogenitor cells -(ANSWER)unspecialized bone stem cells derived from
mesenchyme, the tissue from which almost all connective tissues are formed. They are
the only bone cells to undergo cell division; the resulting cells develop into osteoblasts.
Osteoprogenitor cells are found along the inner portion of the periosteum, in the
endosteum, and in the canals within bone that contain blood vessels
osteoblasts -(ANSWER)bone-building cells. They synthesize and secrete collagen
fibers and other organic components needed to build the extracellular matrix of bone
tissue, and they initiate calcification
osteocytes -(ANSWER)mature bone cells, are the main cells in bone tissue and
maintain its daily metabolism, such as the exchange of nutrients and wastes with the
blood. Like osteoblasts, osteocytes do not undergo cell division
osteoclasts -(ANSWER)huge cells derived from the fusion of as many as 50 monocytes
(a type of white blood cell) and are concentrated in the endosteum. On the side of the
cell that faces the bone surface, the osteoclast's plasma membrane is deeply folded into
a ruffled border. Here the cell releases powerful lys- osomal enzymes and acids that
digest the protein and mineral com- ponents of the underlying extracellular bone matrix
compact bone tissue -(ANSWER)the strongest form of bone tissue. It is found beneath
the periosteum of all bones and makes up the bulk of the diaphyses of long bones.
Com- pact bone tissue provides protection and support and resists the stresses
produced by weight and movement.
80% of skeleton
osteons/haversian systems -(ANSWER)repeating strucutural units in compact bone
tissue. Each osteon consists of concentric lamellae arranged around an osteonic
(haversian or central) canal
concentric lamellae -(ANSWER)circular plates of mineralized extracellular matrix of
increasing diameter, surrounding a small network of blood vessels and nerves located
in the central canal
resemble growth rings of trees
lacunae (plural) -(ANSWER)small spaces between concentric lamellae containing
osteocytes
, BIOL235 MIDTERM EXAM 1 STUDY GUIDE
canaliculi -(ANSWER)small channels radiating out from lacunae, contain extracellular
fluid, connect lacunae with one another
interstitial lamellae -(ANSWER)areas between neighboring osteons, also have lacunae
with os- teocytes and canaliculi. Interstitial lamellae are fragments of older osteons that
have been partially destroyed during bone rebuilding or growth
interosteonic (Volkmann's/perforating) canals -(ANSWER)canals that penetrate
compact bone as patways fo blood vessels and nerves from periosteum
circumferential lamellae -(ANSWER)lamellae arranged around entire inner and outer
circumference of the shaft of long bones, develop during initial bone formation
perforating (aka Sharpey's) fibers -(ANSWER)connect external circumferential lamellae
to the periosteum
spongy bone tissue (aka trabecular/cancellous bone tissue) -(ANSWER)always located
in the interior of a bone, protected by a covering of compact bone, does not contain
osteons. Spongy bone tissue makes up most of the interior bone tissue of short, flat,
sesamoid, and irregularly shaped bones
trabeculae -(ANSWER)lamellae that are arranged in an irregular pattern of thin columns
periosteal arteries -(ANSWER)small arteries accompanied by nerves, enter the
diaphysis through many interosteonic (Volkmann's or perforating) canals and supply the
periosteum and outer part of the compact bone
nutrient artery -(ANSWER)passes through hole in compact bone called nutrient
foramen, found near the center of the diaphysis
metaphyseal arteries -(ANSWER)enter the metaphyses of a long bone and, together
with the nutrient artery, supply the red bone marrow and bone tissue of the metaphyses
epiphyseal arteries -(ANSWER)enter the epiphyses of a long bone and supply the red
bone marrow and bone tissue of the epiphyses
nutrient veins -(ANSWER)accompany the nutrient artery and exit through the diaphysis
epiphyseal veins + metaphyseal veins -(ANSWER)accompany their respective arteries
and exit through the epiphyses and metaphyses, respectively
