BIOL 319 (COHN) TEST 2 EXAM
QUESTIONS AND ANSWERS GRADED A+
2025/2026
Long bones - ANS bones that are longer than they are wide
mostly straight and cylindrical
bulging epiphysis
has a diaphysis (shaft)
examples: upper/lower limbs, clavicle, humerus, distal portion of finger
short bones - ANS bones that are cube/box like
have a epiphyses but not diaphyses
ex: tarsals, carpals, wrist bones
flat bones - ANS bones with an interior framework of spongy bone in-between two layers of
compact bone (some have air filled spaces called sinuses lined by mucous)
ex: sternum, scapula, skill (not temporal), ribs, shoulder blade
irregular bones - ANS bones that are weirdly shaped, have epiphyses similar to long bone but
NO diaphyses
ex: sphenoid bone, vertebrae, facial, temporal bone
sesamoid bone - ANS bones that are almond shaped (irregular but have their own category)
1 @COPYRIGHT 2025/2026 ALLRIGHTS RESERVED.
,ex: knee cap/patella
why is the rib not considered a long bone - ANS it is curved at a major point (should be
straight)
doesn't have a epiphysis
diaphysis is not cylindrical
why or how is the parietal bone a flat bone - ANS has a layer of spongy bone surrounded by 2
layers of compact bone (dipole) and no medullary cavity
explain the medullary cavity (where is it, red or yellow BM) - ANS large cavity within diaphysis
has RED bone marrow from birth-adolescence
after that its yellow bone marrow (fat reserve)
yellow completely replaces red in the long bones except SOME red is left in the proximal part of
the arm and thighs
diaphysis (what is it, what happens here, what is it composed of) - ANS the bone shaft
majority of the length
a lot of compact bone and rest is spongy bone
primary ossification center
articular cartilage (where is this seen, explain hyaline cartilage) - ANS before long bones are
actually bone, they are made of hyaline cartilage converted to bone
this is seen in people undergoing linear growth (thin layer of hyaline forms where a joint is)
epiphysis (what is it, where does it develop from, what happens here) - ANS bulging part of
LONG bone
develops from center of ossification
essential in linear growth
2 @COPYRIGHT 2025/2026 ALLRIGHTS RESERVED.
,epiphyseal line - ANS after growing, hyaline cartilage disappears, epiphyseal plate turns to
this
area of hyaline cartilage betw diaphysis/epiphysis
an "ossified epiphyseal plate"
epiphyseal plate - ANS "growth plate"
critical in long bone growth
when this is gone, no more growth happens and epiphysis and diaphysis fuse together
hyaline cartilage allows bones to grow
spongy bone (where is it, red or yellow, what else is it called) - ANS fills spaces between
trabeculae
this is infested with red bone marrow
also called cancellous or woven bone
osteocytes obtain nutrients through canaliculi
this makes up most of epiphysis
spaces between are filled with bone marrow/blood vessels
is shown in a pattern as we develop/age (the arches make bone sturdier in areas that receive
stress)
compact bone/cortical - ANS bone that is in the middle of the central canal (Haversian)
contains blood vessels where arteries/veins are(also has nerves)
volkmann's canal (perforating canals) are at the right angle of the haversain canals
lacunae contain an osteocyte in them
concentric lammelae - ANS lamellae that is circular layers of bone matrix that surround the
central canal
calcified matrix rings
3 @COPYRIGHT 2025/2026 ALLRIGHTS RESERVED.
, circumferential lamellae - ANS lamellae that are thin plates that compose the outer surface
of compact bone
under the periosteum
interstitial lamellae - ANS lamellae that are the remnants of concentric/circumferential
lamellae that were partially removed during bone remodeling (found between osteons)
endosteum - ANS thin reticular connective tissue membrane that lines the INNER cavities of
the bone
covers the trabeculae (and all other cavities within a bone)
periosteum - ANS the skin of living bone
surrounds bone (EXCEPT where there is hyaline cartilage)
provides place for attachment
highly INNERVATEd and VASCULARIZED
makes the bone shiny
important to the function of living bones (site for bone growth/widening)
inner layer= bone widening
outer layer= protective
ONLY in living bone
composed of DENSE irregular connective tissue
trabeculae - ANS interconnecting rods of bone
lives in interstitial spaces filled with marrow/blood vessels
covered with endosteum
dipole - ANS a layer of spongy bone in between two layers of compact bone (flat bones)
4 @COPYRIGHT 2025/2026 ALLRIGHTS RESERVED.
QUESTIONS AND ANSWERS GRADED A+
2025/2026
Long bones - ANS bones that are longer than they are wide
mostly straight and cylindrical
bulging epiphysis
has a diaphysis (shaft)
examples: upper/lower limbs, clavicle, humerus, distal portion of finger
short bones - ANS bones that are cube/box like
have a epiphyses but not diaphyses
ex: tarsals, carpals, wrist bones
flat bones - ANS bones with an interior framework of spongy bone in-between two layers of
compact bone (some have air filled spaces called sinuses lined by mucous)
ex: sternum, scapula, skill (not temporal), ribs, shoulder blade
irregular bones - ANS bones that are weirdly shaped, have epiphyses similar to long bone but
NO diaphyses
ex: sphenoid bone, vertebrae, facial, temporal bone
sesamoid bone - ANS bones that are almond shaped (irregular but have their own category)
1 @COPYRIGHT 2025/2026 ALLRIGHTS RESERVED.
,ex: knee cap/patella
why is the rib not considered a long bone - ANS it is curved at a major point (should be
straight)
doesn't have a epiphysis
diaphysis is not cylindrical
why or how is the parietal bone a flat bone - ANS has a layer of spongy bone surrounded by 2
layers of compact bone (dipole) and no medullary cavity
explain the medullary cavity (where is it, red or yellow BM) - ANS large cavity within diaphysis
has RED bone marrow from birth-adolescence
after that its yellow bone marrow (fat reserve)
yellow completely replaces red in the long bones except SOME red is left in the proximal part of
the arm and thighs
diaphysis (what is it, what happens here, what is it composed of) - ANS the bone shaft
majority of the length
a lot of compact bone and rest is spongy bone
primary ossification center
articular cartilage (where is this seen, explain hyaline cartilage) - ANS before long bones are
actually bone, they are made of hyaline cartilage converted to bone
this is seen in people undergoing linear growth (thin layer of hyaline forms where a joint is)
epiphysis (what is it, where does it develop from, what happens here) - ANS bulging part of
LONG bone
develops from center of ossification
essential in linear growth
2 @COPYRIGHT 2025/2026 ALLRIGHTS RESERVED.
,epiphyseal line - ANS after growing, hyaline cartilage disappears, epiphyseal plate turns to
this
area of hyaline cartilage betw diaphysis/epiphysis
an "ossified epiphyseal plate"
epiphyseal plate - ANS "growth plate"
critical in long bone growth
when this is gone, no more growth happens and epiphysis and diaphysis fuse together
hyaline cartilage allows bones to grow
spongy bone (where is it, red or yellow, what else is it called) - ANS fills spaces between
trabeculae
this is infested with red bone marrow
also called cancellous or woven bone
osteocytes obtain nutrients through canaliculi
this makes up most of epiphysis
spaces between are filled with bone marrow/blood vessels
is shown in a pattern as we develop/age (the arches make bone sturdier in areas that receive
stress)
compact bone/cortical - ANS bone that is in the middle of the central canal (Haversian)
contains blood vessels where arteries/veins are(also has nerves)
volkmann's canal (perforating canals) are at the right angle of the haversain canals
lacunae contain an osteocyte in them
concentric lammelae - ANS lamellae that is circular layers of bone matrix that surround the
central canal
calcified matrix rings
3 @COPYRIGHT 2025/2026 ALLRIGHTS RESERVED.
, circumferential lamellae - ANS lamellae that are thin plates that compose the outer surface
of compact bone
under the periosteum
interstitial lamellae - ANS lamellae that are the remnants of concentric/circumferential
lamellae that were partially removed during bone remodeling (found between osteons)
endosteum - ANS thin reticular connective tissue membrane that lines the INNER cavities of
the bone
covers the trabeculae (and all other cavities within a bone)
periosteum - ANS the skin of living bone
surrounds bone (EXCEPT where there is hyaline cartilage)
provides place for attachment
highly INNERVATEd and VASCULARIZED
makes the bone shiny
important to the function of living bones (site for bone growth/widening)
inner layer= bone widening
outer layer= protective
ONLY in living bone
composed of DENSE irregular connective tissue
trabeculae - ANS interconnecting rods of bone
lives in interstitial spaces filled with marrow/blood vessels
covered with endosteum
dipole - ANS a layer of spongy bone in between two layers of compact bone (flat bones)
4 @COPYRIGHT 2025/2026 ALLRIGHTS RESERVED.
