Chapter 7 PPT Flashcards
Bones are composed of what tissues?
Bone Tissue
Cartilage
Dense Connective Tissue
Blood and Nervous Tissue
Bones of the skeletal system vary greatly in these ways
Size and Shape
Bones are similar in what functions?
Structure
Development
Function
How are long bones classified?
Long and Narrow
Have Expanded Ends
How are short bones classified?
Cube-Like, Length=Width Includes Sesamoid (Round) Bones Embedded in Tendons
How are flat bones classified?
Plate-like, with broad surfaces
How are irregular bones classified?
Variety of Shapes
Most are connected to several other bones
What is a epiphysis?
Expanded Shaft
What is a Diaphysis?
Bone Shaft
Where is a Metaphysis?
Between diaphysis and epiphysis, widening part
What is articular cartilage?
Covers epiphysis
What is the Periosteum?
Encloses bone, made of dense connective tissue
What is a compact (cortical) bone
Wall of diaphysis
What is a spongy (cancellous) bone
Makes up epiphyses
What is a trabeculae
branching bony parts, make up psongy bone
what is the medullary cavity?
Hollow chamber in diaphysis; contains marrow
what is the endosteum?
lines spaces, cavity
what is bone marrow?
red or yellow marrow, lines medullary cavity, spongy bone spaces
Mature bone cells are called
osteocytes
Osteocytes occupy chambers called
lacunae
What are canaliculi?
Osteocytes exchange nutrients and wastes via cell processes within tiny passageways
The ECM of bone is largely
collagen fibers and irganic salts
Bones - collagen gives bone
resilience
Bones - inorganic salts make bone
hard
Compact bone consists of cylindrical units called
osteons
compact bone characteristics
strong and solid
weight-bearing
resists compression
spongy bone consists of branching plates called
trabeculae
spongy bone characteristics
somewhat flexible
has spaces between trabeculae that reduce that bone weight
compact bone consists of
osteons
compact bone have osteocytes in
lacunae
compact bone has lamellae, that are
layers of matrix around central canal
compact bone has osteons that are
cemented together by bone matrix
compact bone has what type of canals?
perforating canals, that join adjacent central canals
compact bone, osteocytes can pass nutrients through
canaliculi
bones form when bone tissue replaces existing connective tissue in what two ways?
intramembranous bones
endochondral bones
Bone Development in 14-Week Fetus: Intramembranous Ossification
Flat skull bones, clavicles, sternum, and some facial bones are forming between sheets of primitive connective tissue
Bone Development in 14-week fetus: Endochondral Ossification
Long bones and most of skeleton are forming from hyaline cartilage models
Intramembranous bones originate within
sheet-like layers of connective tissue
intramembranous bones are
broad, flat bones
examples of intramembranous bones
flat bones of the skull, clavicles, sternum, and some facial bones
intramembranous ossification is the process of
replacing embryonic connective tissue to form intramembranous bone
intramembranous ossification - mesenchymal cells..
in primitative tissue differentiate into osteoblasts
intramembranous ossification - osteoblasts
bone-forming cels that deposit bone matrix around themselves
intramembranous ossification - when osteoblasts are completely surrounded by matrix
they are now osteocyte sin lacunae
intramembranous ossification - mesenchyme on outside form
periosteum
Endochondral bones begin as
masses of hyaline cartilage
endochondral bones consist of most
bones of the skseleton
examples of endochondral bones?
femur, humerus, radius, tibia, phalanges, vertebrae
endochondral ossification is the process of
replacing hyaline cartilage to form an endochondral bone
endochondral ossification begin as
hyaline cartilage models
in endochondral ossification, chondrocytes
enlarge, lacunae grow
in endochondral ossification, matrix
breaks down, chondrocytes die
in endochondral ossification, osteoblasts
invide area, deposit bone matrix.
form spongy and then compalct bone
in endochondral ossification, once encased by matrix
osteoblasts are now osteocytes
First Step in Intramembranous Ossification
Sheets of embryonic connective tissue (mesenchyme) appear at the sites of future bones.
Second Step in Intramembranous Ossification
Mesenchymal cells differentiate into osteoblasts, which deposit bone matrix.
Third Step in Intramembranous Ossification
Dense networks of blood vessels supply the developing spongy bone.
Fourth Step in Intramembranous Ossification
- Osteoblasts become osteocytes when bony matrix completely surrounds them.
Fifth Step in Intramembranous Ossification
Mesenchyme on the surface of each developing structure condenses to form periosteum.
Sixth Step in Intramembranous OSsification
Osteoblasts on the inside of the periosteum deposit compact bone over the spongy bone.
First Step in Endochondral Ossification
Masses of hyaline cartilage form models of future bones.
Second Step in Endochondral Ossification
- Cartilage tissue breaks down. Periosteum develops.
Third Step in Endochondral Ossification
- Blood vessels and differentiating osteoblasts from the periosteum invade the disintegrating tissue.
Fourth Step in Endochondral Ossification
- Osteoblasts form spongy bone in the space occupied by cartilage.
Fifth Step In Endochondral Ossification
- Osteoblasts beneath the periosteum deposit compact bone.
Sixth Step in Endochondral Ossification
- Osteoblasts become osteocytes when bony matrix completely surrounds them.
In a growing long bone, diaphysis is separated from epiphysis by
Epiphyseal plate, region at which bone grows in length
Cartilaginous Cells of Epiphyseal Plate form what layers?
Zone of Resting Cartilage
Zone of Proliferating Cartilage
Zone of Hypertrophic Cartilage
Zone of Calcified Cartilage
Zone of Resting Cartilage layer location
layer closest to end of epiphysis
zone of resting cartilage consists of
resting cells that anchor epiphyseal plate to epiphysis
zone of proliferating cartilage is
rows of young cells, undergoing mitosis
zone of hypertrophic cartilage are
rows of older cells left behind when new cells appear. Thicken epiphyseal plate, lengthening the bone
zone of hypertrophic cartilage does?
matrix calcifies, cartilage cells (chrondrocytes die)
zone of calcified cartilage are
thin layer of dead cartilage cells and calcified matrix
Growth of epiphyseal plate - osteoclasts…
break down calcified matrix
Growth of epiphyseal plate - osteoblasts then
invade, replacing cartilage with bone tisue
Growth of epiphyseal plate - bone can
continue to grow in length, as long as cartilage cells of epiphyseal plate remain active
Growth of epiphyseal plate - when ossification centers meet and epiphyseal plate ossifies..
bone can no longer grow in length
Growth of epiphyseal plate - bone can thicken by
depositing compact bone on outside, under periosteum
Ossification - At third month of prenatal development…
ossification in long bone begins
Ossification - at fourth month of prenatal development…
most primary ossification centers have appeared in the diaphysis of long bones
Ossification - from birth to five years..
secondary ossification centers appear in the epiphyses of long bones
Ossification - from 5 - 14 years old…
ossification rapidly spreads from the ossification centers
Ossification - from 15-20 years old…
bones of the upper limbs and scapulae completely ossified
Ossification - from 18-23 years old…
bones of the lower limbs and hip bones completely ossified
Ossification - from 23-25 years old..
bones of the sternum, clavicles, and vertebrae completely ossified
Ossification - by 25 years old…
nearly all bones completely ossified
What is bone resorption?
Removal of bone, action of osteoclasts
what is bone deposition?
formation of bone, action of osteoblasts
how much of skeleton is replaced every year?
10% - 20%
What does vitamin d do?
calcium absorption
deficiency of vitamin d causes?
rickets, osteomalacia
what does vitamin a do?
osteoblast and osteoclast activity.
deficiency of ivitamin a?
retards bone development
what does vitamin c do? deficiency?
collagen synthesis?
Results in slender, fragile bones
what does the growth hormone do?
stimulates cartilage cell division?
what does growth hormone insufficiency/excess do?
insufficiency in a child can result in dwarfism.
excess causes gigantism in child
What does thyroid hormone do?
causes replacement of cartilage with bone in epiphyseal plate, osteoblast activity
what does parathyroid hormone (PTH) do?
stimulates osteoclasts, bone breakdown
what do sex hormones do?
promote bone formation ; stimulate ossification of epiphyseal plates
what does physical stress do to bones?
stimulates bone growth
What is a simple (closed) fracture?
fracture protected by uninjured skin (or mucous membrane)
what is a compound (open) fracture?
fracture in which the bone is exposed to the outside through opening in skin (or mucous membrane)
What is a greenstick fracture?
is incomplete, and the break occurs on the convex surface of the bend in the bone
what is a fissured fracture?
an incomplete longitudinal break
what is a comminuted facture?
is complete and fragmented bones
what is a tranverse fracture?
is complete, and the break occurs at a right angle to the axis of the bone
what is a oblique fracture?
occurs at an angle other than a right angle to the axis of the bone
what is a spiral fracture?
caused by excessive twisting of the bone
What is Hematoma?
large blood clot
what is cartilaginous callus?
phagocytes remove debris, fibrocartilage invades
what is bony callus?
osteoblasts invade, hard callus fills space
what is remodeling?
bone restore close to original shape?
what are the steps in fracture repair?
Hematoma
Cartilaginous Callus
Bony Callus
Remodeling
bones provide
shape to body
bones support
body structure
bones protect
body structures
bones aid
body movements
bones contain
tissue that produces blood cells
bones store
inorganic salts
What is hematopoiesis?
blood cell formation
blood cell production occurs in
red bone marrow
rbc, wbc, and platelets are produced in
red blood marrow
with age, some red bone marrow is replaced by
yellow bone marrow, which only stores fat
About 70% of bone matrix consists of
inorganic mineral salts
most abdundant salt is crystals of
calcium phosphate
what is osteoporosis?
a condition that results from loss of bone mineralization
what is a fragility fracture?
fracture that occurs after a fall from less than standing height, a sign of low bone density
with age, osteoclasts remove
more bone tissue than osteoblasts produce
how many bones are in the adult skeleton?
206 bones
What does the Axial Skeleton contain?
Skull Middle Ear Bones Hyoid Vertebral Column Thoracic Cage
What does the Appendicular Skeleton contain?
Pectoral Girdle
Upper Limbs
Pelvic Girdle
Lower Limbs
Bones in middle ear?
Malleus
Incus
Stapes
How many cervical vertebra are there?
7
how many thoracic vertebra are there?
12
how many lumbar vertebra are there?
5
how many sacrum are there?
1
how many coccyx are tehre?
1
BOnes of the Vertebral column?
Cervical Thoracic Lumbar Sacrum Coccyx
how many ribs are tehre?
24
BOnes in pectoral girdle?
Scapula and Clavicle
condyle definition?
rounded process that usually articulates with another bone
crest definition
narrow, right-like projection
epicondyle definition
projection situated above a condyle
facet definition?
small, nearly flat surface
fissure definition?
cleft or groove
fontaneal definition
soft spot in the skull where membranes cover the space between bones
foramen definition
opening through a bone that usually serves as a passageway for blood vessels, nerves, or ligaments
fossa definition
relatively deep pit or depression
fovea definition
tiny pit or depression
head definition
enlargement on the end of a bone
linea definition
narrow ridge
meatus definition
tube-like passageway within a bone
process definition
prominent projection on a bone
ramus definition
branch or similar extension
sinus deifnition
cavity within a bone
spine deifnition
thorn-like definition
sulcus definition
furrow or groove
suture definition
interlocking line of union between bones
trochanter definition
relatively large process
tubercle definition
knob-like process
tuberosity definition
knob-like process usually larger than a tubercle
How many bones are in the skull?
22
all skull bones are interlocked along sutrues, except
the lower jaw (mandible)
cranium contains
8 bones; encloses and protects brain
facial skeleton contains
14 bones, forms shape of face
What are fontanels?
Fibrous membranes that connect cranial bones, where intramembranous ossification is incomplete
vertebral column consists of many vertebrae separated by
cartilaginous intervertebral discs, and connected by ligaments
how many bones in vertebral column for an infant
33
how many bones in vertebral column for an adult
26
Atlas location?
C1, supports head
Axis location?
C2, atlas pivots around the dens
Cervical vertebrae in the neck region are the smallest
vertebrae
cervical vertebrae bifid spinous process goes from
C2-C6
Cervical vertebrae - C7 consists of
vertebral prominens
thoracic vertebrae articulate with
ribs
thoracic vertebrae look like
long, pointed spinous process
lumbar vertebrae main function?
weight-bearing
sacrum consists of how many fused vertebrae?
5
coccyx consists of how many fused vertebrae?
4
What is a Herinated or Ruptured Disc?
Break in the outer protion of an intervertebral disc. Compresses spinal nerves, causing numbness, pain, and loss of muscle function
what is kyphosis?
exaggerated thoracic curvature of the spine, rounded shoulders and hunchback, causes by poor posture, injury, disease
what is scoliosis?
abnormal lateral curvature of the spine.
One shoulder or hip may may be lower than the other
what is lordosis?
exaggerated lumbar curvature of the spine, swayback
what are compression fractures?
factures of vertebral bodies become more common with age as intervertebral discs become rigid and shrink.
how many pairs of true ribs?
7
how many pairs of false ribs?
5
what are vertebronchondral ribs?
upper 3 pairs of false ribs
what are floating ribs?
lower 2 pairs of false ribs
what does the head of the rib articulate with?
vertebrae
what does the tubercle of the rib articulate with?
the vertebrae
what does the costal cartilage in the rib connect to?
sternum
what does the sternum articulate with?
costal catilages and clavicles
what does the clavicle articulate with?
manubrium and scapulae
radius are shorter than the
ulna
hip bones are also called
coxal bones
hip bones consist of what 3 fused bones
illium
ischium
publis
