Vet A&P Skeletal

5 functions of skeletal system

1. support

2. locomotion

3. protection

4. storage

5. haemopoiesis

The skeletal system acts as an internal _____ upon which the body is built

scaffold

The skeletal system provides ____ for muscles, which operate a system of levers (___) to bring about locomotion

attachment, bones

The skeletal system ____ the underlying soft parts of the body

protects (brain encased in skull)

The skeletal system acts as a store for essential minerals ____ and _____

calcium and phosphate

_____ tissue forming the ______ manufactures the blood cells

haemopoietic, bone marrow

7 types of bones

long, flat, short, irregular, sesamoid, pneumatic, splanchnic

long bones have a shaft containing a ______ filled with bone marrow

example: ____

medullary cavity

limb bones (femur, humerus), metacarpus, metatarsus, phalanges

flat bones have an outer layer of ____ bone and inner layer of _____ bone

example: ___

compact, cancellous/spongy

bones of the skull, scapula, ribs

T/F: Flat bones have no medullary cavity

True

short bones have an outer layer of ____ bone and core of _____ bone

example: ___

compact, cancellous/spongy

carpal and tarsal bones

T/F: short bones have a medullary cavity

False

irregular bones have a similar structure to ____ bones, but a less uniform shape and are ___

example: ___

short, unpaired

vertebrae

sesamoid bones develop within a _____ that runs over an underlying bony prominence

example: ____

tendon

patella associated with stifle joint

sesamoid bones serve to change the ____ at which the tendon passes over the bone and ____

angle, reduce wear and tear

pneumatic bones contain ____ known as _____ that have the effect of ___

example: ___

air-filled sacs, sinuses, reduce weight

maxillary and frontal bones

splanchnic bone develops in a ____ and is ____ to the rest of the skeleton

example: ____

soft organ, unattached

os penis

the process by which bone is formed is ___

ossification

in ____ ossification there is no cartilage template or model

intramembranous

in intramembranous ossification ___ lay down bone between ___

osteoblasts, two layers of fibrous connective tissue

flat bones of the skull are formed by ____ ossification

intramembranous

____ ossification involves the replacement of a ___ model within the embryo by bone

endochondral, hyaline cartilage

long bones of the limb develop by ____ ossification

endochondral

steps of endochondral ossification

1. cartilage model develops within embryo

2. Primary center of ossification appears in the diaphysis (shaft)

3. Secondary center of ossification appears in the epiphysis (end)

4. osteoclasts remove bone from center to form marrow cavity. osteoblasts continue laying bone in outer edges

5. growth/epiphyseal plate (narrow band of cartilage) appears between diaphysis and epiphysis

when the animal has reached final size, the ____ is replaced by bone and growth will no longer be possible

growth/epiphyseal plate

limb deformaties can occur when a _____ is abnormal or damaged by trauma

growth plate, causes bone to stop growing and shorten

carpal valgus and carpal varsus

angular limb deformaties (outward or inward twisting of paw)

bulldog and shihtzu bred to have this confirmation

articular projections

head, condyle, trochlea, facet

articular depressions

fovea, glenoid cavity, notch

non-articular projections

process, tuberosity, tubercle, spine, crest, neck, linea

non-articular depressions

fossa, foramen, canal

trochanter

LARGE non-articular projection for attachment of muscles on femur

tuberosity (tuber)

LARGE non-articular projection for attachment of muscles

tubercle (tuberculum)

SMALL non-articular projection for attachment of muscles

trochlea

articular grooves in long bone that allow tendons to act as pulleys

head

articular spherical projection for articulation with another bone

condyle

articular cylindrical projection for articulation with another bone

epicondyle

projection on lateral edge above condyle

facet

flat articular surface

foramen (pl. foramina)

opening for passage of blood vessels and nerves

fossa

hollow depression

head, neck, shaft

describe parts of long bone

tendon

connects muscle to bone

ligament

connects bone to bone

bones of the head (4)

skull, nasal chambers, mandible, hyoid apparatus

6 functions of the skull

1. house and protect brain

2. house sense organs (eye, ear, nose, tongue)

3. house and provide attachment for digestive system (teeth, tongue)

4. provide attachment for hyoid apparatus and muscles of mastication and facial expression

5. provide bony cavity through which air can enter body

6. communicate (muscles of facial expression)

incisive bone

nasal bone

lacrimal bone

orbit

frontal bone

parietal bone

maxilla

zygomatic bone

sphenoid complex

temporal bone

external auditory meatus

occipital condyles

occipital bone

the caudal part of the skull where the brain sits is the ____

cranium

incisive bone

maxilla

palatine bone

zygomatic arch

jugular process

occipital condyle

formamen magnum

occipital bone

the ____ in the ___ bone house the structures of the middle ear

tympanic bulla, temporal

the ____ opens into the tympanic bulla of the temporal bone

external acoustic meatus (ear canal)

the ___ articulate with the first cervical vertebra (atlas)

occipital condyles

the ___ forms the floor of the cranial cavity and has many foramina

sphenoid

the ___ is a ridge of bone on the skull prominent in muscular breeds

sagittal crest

poor development of the skull can result in ____, causing herniation of the ___ through foramen magnum

small cranium (insufficient to accommodate size of brain), cerebellum

hydrocephalus

fluid on the brain

syringomyelia

fluid filled cavities of the spine

ataxia

uncoordinated gait

the nasal chamber is divided by a cartilaginous plate called the ____

nasal septum

many bones of the skull are joined together by fibrous joints called ____ that allow for ____

sutures, growth and expansion

nasal conchae

boundary between nasal and cranial cavities

ethmoid

olfactory nerve passes

cribiform plate

pterygoid

incisors

canine tooth

premolars

molars

mandibular notch

coronoid process

condylar process of mandible

angular process of mandible

masseteric fossa

condylar process of mandible

ramus of mandible

first molar

mandibular symphysis

body of mandible

The mandible (lower jaw) comprises two halves called _____ joined together at the _____

dentaries, mandibular symphysis

Each half of the mandible is divided into ___ (horizontal part) and ____ (vertical part)

body, ramus

the body of the mandible carries the ____ for the teeth

sockets (alveoli)