PHYL 141 -exam 2

Osterology

"chondro-" = cartilage • "osteo- "/"oss- " = bone

osteology = study of bones

sutural bones

sutures

a.k.a. "Wormian" bones

irregular bones

vertebra

short bones

carpal bones

flat bones

parietal bone

long bones

humerus

sesamoid bones

patella

boen markings:

projections-->

depressions & openings-->

--> attach to things; e.g.. tendons, ligaments, and/or fit into something (e.g. condyles and heads)

--> make room for things; e.g. organs, or allow things to pass through (e.g. blood vessels, nerves)

condyle

"knuckle" -Grk. kondulos -Lat. condyles

Epiphysis

at the Ends

diaphysis

in the center like a diameter

metaphysis

where an epiphysis meets a diaphysis

Periosteum & Endosteum

"peri-" = around, like perimeter & "endo-" = internal, within

Bone is a connective tissue

Ground substance = bone mineral (calcium phosphate & salts)

Fibers = strong collagen fibers in multiple directions
Specialized cells

Bone Ground Substance

Calcium phosphate
Crystallized form: Hydroxyapatite
Bone mineral is less crystallized

bone

is a hard substance with flexible strong fibers

ground substance

bone mineral (calcium phosphate & salt)

fibers

strong collagen fibers in multiple directions

OsteoBlasts

Build

Osteogenic cells

stem cells

Osteogenic cells generate osteoblasts

OsteoClasts

Crush

osteogenesis

bone formation

ossification

the process of forming bone

tissue becoming bone

calcification

deposition of calcium salts

Intramembranous (Dermal) Ossification

Produces dermal bones: mandible, clavicle

during fetal development

no cartilage required

Endochondral OSsification

"endo-" = inside, inner, within

replaces hyaline cartilage with bone

most bones start as hyaline cartilage

Bone growth

Width=
Appositional
Interstitial
Length

Thickness
Appositional
Interstitial
Length

Epiphyseal plates (growth plates)

Hyaline cartilage
• Site of new bone growth
• Human bones grow until about age 25
• Cartilage completely replaced by adulthood
-Epiphyseal line

Calcitriol - Calcium absorption

Made in kidneys
• Made from vitamin
D
• Increases calcium & phosphate absorption from food
• Increases reabsorption of Ca2+ from the blood

Parathyroid Hormone Action

1.Activate osteoclasts
2.↑Ca2+ absorption in GI
3.↑kidney calcitriol production

Calcitonin Hormone Action

1.↓ osteoclast activity
2.↓ Ca++ absorption
3.↓ calcitriol production

As osteoclasts absorb and remove bone matrix, they leave shallow depressions called a(n) _________.

osteoclastic crypt

The term for the expanded end of a long bone where the joint surfaces are located is the __________.

epiphysis

Spongy bone is found primarily at which part of long bones?

Expanded ends, where long bones articulate with other skeletal elements

Unlike compact bone, spongy bone (also called cancellous bone) resembles a network of bony struts separated by spaces that are normally filled with __________.

bone marrow

Narrow passageways that allow osteocytes to communicate with neighboring osteocytes are called _____________.

canaliculi

Even as an adult, we have populations of primitive cells that can produce osteoblasts. These primitive cells are called __________.

osteogenic cells

Mature bone cells found in lacunae are called __________.

osteocytes

Which of the following are NOT structural components of compact bone?

trabeculae

The spaces in the bony matrix where osteocytes exist are ____________.

lacunae

Canals that extend perpendicularly through bone to supply blood to deeper osteons and to tissues of the medullary cavity are ___________________ canals.

perforating

The basic functional unit(s) of compact bone tissue is/are _____________.

an osteon

Giant, multinucleated cells involved in the process of osteolysis are __________.

osteoclasts

Compact bone is characterized by many cylindrical osteons. Osteons are formed by layers of nested cylinders each called a(n) _____________.

lamella

The fibers of tendons intermingle with those of the periosteum, attaching __________.

skeletal muscles to bones

Cells that produce new bone matrix are called __________.

osteoblasts

The small passageways that exist in the bone matrix to allow living bones cells to obtain nutrients and get rid of wastes are called __________.

canaliculi

The meshwork of supporting bundles of fibers that make up spongy bone are __________.

trabeculae

How is the tendon connected to a bone so that it will withstand the force that must be applied by the muscle to move the bone?

The collagen fibers of the tendon as well as the periosteum are incorporated into the bone tissue.

correct

The region known as the epiphyseal plate is the area where __________.

cartilage is not replaced by bone until after puberty

Which of the following is false regarding vitamin C and bone health?

It can also be produced in the skin

Which of the following types of bone cells are responsible for removing and recycling bone?

osteoclasts

The outer dense connective tissue of a bone, the periosteum, ________.

isolates the bone from surrounding tissues, provides a route for circulatory and nervous supply, and actively participates in bone growth and repair

The process of bone breakdown or erosion is called __________.

osteolysis

The endosteum is found in all of the following places except the __________.

covering the outside surface of the bones

Two-thirds of a bone's weight is composed of calcium phosphate which interacts with calcium hydroxide to form crystals of __________.

hydroxyapatite

skull bones

8 cranial - protect the brain
14 facial - protect facial entrances to the body

cranial bones

2x Parietal
Ethmoid
Sphenoid
2x Temporal
Occipital
Frontal

articulation

joint; point of contact between two bones

Facial Bones

Vomer
Conchae
Nasal
Maxilla
Mandible
Palatine
Zygomatic
Lacrimal
Vicky
Can
Not Make
My Pupils
Zap
Lasers

lacrimal

relating to tears

The nasal complex

Nasal Cavities + Paranasal Sinuses = Nasal Complex
-Inferior nasal conchae -Nasal bone
-Lacrimal bone
- Sinuses: • Frontal
• Sphenoid
• Maxilla
• Ethmoid (air cells)

The sinuses, or internal chambers in the skull, are found in the __________.

sphenoid, frontal, ethmoid, and maxillary bones

The bones that make up the eye socket, or orbit, include the __________.

lacrimal, ethmoid, and sphenoid

The mucus secreted by the nasal epithelium does all of the following EXCEPT

make air flow easier

Airflow in the nasal cavity is made turbulent by the

nasal conchae

In which of the following groups does each bone contain a sinus?

ethmoid, sphenoid, frontal, and maxillary

Which fontanelle might indicate dehydration in an infant ?

Anterior fontanelle

The growth of the cranium is usually associated with

the expansion of the brain

Which of the following is NOT likely to cause kyphosis?

Abdominal obesity causing an exaggeration of the lumbar curvature

Which bones make up the nasal septum?

Ethmoid and vomer

Why can the skull be distorted without damage during birth?

Fibrous connective tissue connects the cranial bones.

What feature of the skeleton eventually allow a child to maintain balance while walking and running?

The secondary curves of the vertebral column

Which of the following is the largest fontanelle and is commonly called the "soft spot" in newborn babies?

Anterior fontanelle

The primary spinal curves that appear late in fetal development

accommodate the thoracic and abdominopelvic viscera

Which bones are part of the bridge of the nose?

Nasal bones

The area of the greatest degree of flexibility along the vertebral column is found from

C3 to C7

The nasal complex consists of

all of the listed bones and structures are correct

The mucous membrane of the paranasal sinuses respond to environmental stress by

accelerating the production of mucous

Why does the most significant growth in the skull occur before 5 years of age?

The brain stops growing, and cranial sutures develop.

Humans are distinguished from many animals by having an upright body position. What parts of the skeleton help us maintain the upright body position?

The vertebral column

Which of the following bones is NOT part of the orbital complex?

Temporal bone

Which bone forms the lateral wall and rim of the eye orbit?

Zygomatic

The passageway that allows the optic nerve to reach the eyeball for the sense of vision is the

optic canal

Which bones form the medial wall of the eye orbit?

Maxilla, lacrimal, and ethmoid

An abnormal lateral curvature of the spine is called

scoliosis

The sutures that articulate the bones of the skull are the ________________ sutures

lambdoidal, sagittal, coronal, and squamous

The sagittal suture joins

the parietal bones to each other

What happens during a sinus infection (sinusitis)?

Inflamed Sinus Lining
Excess Mucus/ Sinus Infection