Anatomy Lecture Exam 2

Chapters 5 - 8

skeletal system

contains

• skeleton: axial and appendicular

• cartilage

• ligaments

axial skeleton

bones of the head, trunk, vertebral column and thorax

appendicular skeleton

limbs, pectoral girdle, pelvic girdle

skeletal system functions

• support: framework for attachment of other organs

• movement/locomotion

• storage of minerals: calcium and phosphate ions

• blood cell production

• protection

osseous tissue

matrix of bone consists of:

• hydroxyapatite crystals

  • calcium phosphate make up 2/3 of bone mass

• collagen fibers

  • make up 1/3 of bone mass

  • contribute to tensile strength of bones

• bone cells (2%)

osteocytes

maintains matrix; mature not actively producing matrix

• matian protein and mineral content of matrix

• resides in lacunae

• controls release and deposition of Ca2+ in/out of bone

osteoblasts

produce matrix; immature, active bone cells

• found on inner & outer surfaces of bones

• produce osteoid

• osteogenesis

osteoprogenitor cells

produce osteoblasts (bone stem cells)

• innermost layer of periosteum and inner lining of endosteum

• involved in repair of bones after a fracture

osteoclasts

break down matrix

• multinucleated cells

• maintain calcium ions in actual blood stream

• osteolysis

osseous tissue types

compact bone and spongy bone

compact bone

• dense bone

• dense and solid

• forms walls of boen

• parallel compression

spongy bone

• trabecular bone

• open network of platelets

• multidirectional or light strain

• surround medullary cavity

epiphysis

heads of long bone; houses red marrow for RBC formation

diaphysis

shaft of long bones; houses yellow-marrow

medullary cavity

inner cavity of diaphysis

epiphyseal line

“growth line”

periosteum

• membrane on outer surface of bone

• fibrous layer & osteogenic layer

• isolates and protects bone from surrounding tissue

• attachment for circulatory and nervous supply

• attachment site for tendons and ligaments

endosteum

• membrane on inner surface of bone; single, incomplete cell layer

• lines medullary cavity, perforating canals and central canals

appositional growth

• osteoblasts in periosteum add bone matrix to surface

• forming circumferential lamellae on outer surface

• osteons are formed

• osteoclasts break down layer below endosteum to enlarge medullary cavity

bone age is set by age 25

factors regulating bone growth

minerals: magnesium, calcium, phosphate, citrate, carbonate

vitamins

• A: stimulates osteoblasts

• C: collagen formation and osteoblast differentiation

• D3: used for calcitriol by kidneys

parathyroid hormone (PTH)

• stimulates osteoclasts

• increases circulating Ca2+

• influence production of calcitriol in kidney

calcitonin

• produced by thyroid gland

• inhibits osteoclasts

• decreases circulating Ca2+

thyroxine

• growth hormone

• influence basal metabolic rate of bone cells

• maintain activity in epiphyseal region for growth

estrogen & testosterone

• important for maintaining osteoblasts

• stimulate osteoblast activity causing growth spurts during puberty

• maintain bone density in adults

sutural bones

• attached by sutures

• small, flat, oddly shaped bones

• found between flat bone of the skull along sutures

pneumatized bones

• hollow or contain lots of air pockets

• ex: ethmoid bone

sesamoid bones

• found in joints

• ex: patella

• small, round, flat

• most often found near joints at knee, hands, and feet

• embedded in tendons

temporal process of zygomatic bone

A

zygomatic process of temporal bone

B

zygomatic arch

C

parietal bone

D

squamous suture

E

lambdoid suture

F

occipital bone

G

temporal bone

H

external acoustic meatus

I

Mastoid process

J

styloid process

K

coronal suture

L

frontal bone

M

sphenoid

N

Nasal bone

O

lacrimal bone

P

lacrimal groove

Q

ethmoid

R

maxilla

S

infraorbital foramen

T

zygomatic bone

U

mandible

V

mental foramen

W

coronoid process

X

sternum

A

manubrium

B

body of sternum

C

xiphoid process

D

costal cartilages

E

floating ribs (11-12)

F

true ribs (1-7)

G

false ribs (8-12)

H

hyoid

A

frontal

B

coccyx

C

maxillae

D

frontal bone

A

frontal sinus

B

Nasal bone

C

ethmoid

D

superior conchae

E

middle conchae

F

Inferior conchae

G

Nasal conchae

H

maxilla (bony palate)

I

sphenoid

J

sphenoidal sinus

K

palatine bone

L

name the bones

a) ethmoid

b) temporal

c) sphenoid

coronal suture

A

frontal sinuses

C

nasal bone

D

ethmoid

E

crista galli

F

cribriform plate

G

perpendicular plate

H

vomer

I

maxilla

J

palatine bone

K

parietal

M

sphenoid

N

Hypophyseal fossa

O

sphenoidal sinus

P

squamous suture

Q

temporal

R

internal acoustic meatus

S

lambdoid suture

U

styloid process

T

occipital

V

foramen magnum

W

concentric lamellae

A

interstitial lamellae

B