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I-Body

Dog & Cat Anatomy Questions & Answers I-Body
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Medial
closer to the midline of the body or median plane
Lateral
further from the median plane
Cranial
toward the head
Caudal
toward the tail
Ventral
toward the ground ("Down")
Dorsal
away from the ground, for the distal limbs, away from the tail
What surfaces below the "top" (proximal end) of the carpus/tarsus are directed toward the tail or ground?
Palmer and Plantar
Proximal
near to the body or point of origin
Distal
far from the body or point of origin
For what is the term peripheral used to describe?
a part distal from its point of origin or near the surface
Axial
closer to the longitudinal axis of the limb
Abaxial
farther from the longitudinal axis of the limb
Where is the axis of the limb in relation to the digits?
between the 3rd and 4th digits
External vs. Internal
closer to the outer surface of the body vs. closer to the center surface of the body
Superficial vs. Deep
closer to the surface vs. internal to the surface
Sagittal plane
divides body into unequal right/left portions, parallel to median plane
Median (mid-sagittal) plane
divides body into equal right/left portions
Transverse plane
perpendicular to the median plane, divides body into caudal/cranial portions
Cross section
a cut through the transverse plane of a structure
What are sections? List two.
cuts through planes of the body to display internal structures (Transverse & Longitudinal)
Human terms
anterior=cranial, posterior=caudal, superior=dorsal, inferior=ventral; correctly applied when used for the eye & some other head structures
The skeleton can be divided into ___, ___ and visceral portions.
axial, appendicular
Name 3 parts of the axial skeleton
Skull, spinal column, thorax
The vertebral column consists of what five regions?
CTLSC
What connects the thoracic girdle to the axial skeleton?
Muscle attachments (synarcosis)
List the regions of the thoracic limb and the bones each includes.
shoulder: scapula
brachium: humerus
antebrachium: ulna and radius
carpus: carpal bones
manus: carpal, metacarpal, phalangeal and sesamoid bones
digits: prox., middle, distal phalanges and associated sesamoid bones
List the regions of the pelvic limb and the bones each includes.
Pelvis/pelvic girdle: hip bones (ilium, pubic, ischium), sacrum and first few caudal vertebrae
Thigh: femur
Stifle: femur, tibia, and fibula
Crus: tibia and fibula
Tarsus/hock: tarsal bones
Pes: tarsal, metatarsal, phylangeal, and sesamoid bones
Digits: proximal, middle, distal phalanges and associated sesamoid bones
What are the parts of a long bone?
Two ends: epiphysis
Body: diaphysis
In endochondral (intracartilaginous) ossification, where are the centers of ossification located?
diaphysis and two epiphyses
Lengthening of long bones occurs in what area?
outer growth plate (epiphyseal side)
What are the two different types of growth plates? give examples of each.
Traction: olecranon, calcaneus
Compression: most of the rest
Structural classification groups joints according to their ____ ____.
uniting medium
What are three types of uniting medium of joints in the structural classification?
Fibrous, cartilaginous, synovial
A suture is what type of structural joint? movement?
fibrous (immovable)
Is a gomphosis (implantation of teeth in the jaw) a true joint?
No, because teeth aren't part of the skeleton
Where are symphyseal joints found?
Generally on the midline of body
What type of joint occurs between the bodies of most vertebrae?
Symphyseal-intervertebral disc
Ginglymus or hinge
Flexion and extension (elbow)
Plane joint
Gliding or sliding (carpal bones)
ball-and-socket/spheroidal
universal movement (shoulder and hip)
pivot joint
rotation around a longitudinal axis (atlantoaxial joint)
Condylar joint
flexion and extension/rotation (stifle)
Most of the joints of the thoracic and pelvic limb have what type of ligaments? Which joints don't?
collateral ligaments; shoulder and hip
What five things characterize a synovial joint?
Mobility, articular cartilage, joint capsule, synovial fluid, joint cavity
What covers the articular ends of bones?
articular cartilage, usually hyaline cartilage
What is the nerve and vascular supply in articular cartilage?
doesn't have any
How does articular cartilage receive nutrition and remove waste?
Synovial fluid, as it has no blood supply
Where are bursae located?
between skin and bones, tendons and bones, muscles and bones, or ligaments and bones
What is the function of a bursa?
reduce friction between structures
What structure, similar to a bursa, is completely wrapped around a tendon?
a synovial sheath
where are synovial sheaths commonly found?
carpus, tarsus, digits
what is the function of a synovial sheath?
reduces friction on a tendon as it crosses a number of joints
what is the configuration of the shoulder joint?
ball-&-socket joint (spheroidal)
List the joints of the manus and the bones they are between.
*Carpus:
-Antebrachial (radius and ulna and carpal bones)
-middle carpal (proximal and distal carpal rows)
-carpometacarpal joints (distal carpal and metacarpal bones)
*Metacarpophalangeal (MP) joint (metacarpal bone and a proximal phalanx)
*Proximal interdigital (PIP): proximal and middle phalanges
*Distal interdigital (DIP or "claw") joint: middle and distal phalanges
with what do the proximal ends of the ribs articulate? Distal ends?
thoracic vertebrae; sternum
name the fibrocartilages between the bodies of adjacent vertebrae.
intervertebral discs
What is the relatively immovable joint between the sacrum and ilium?
sacroiliac joint
name the ball-and-socket joint of the pelvic limb
hip joint, coxofemoral, or coxal joint
what are the fibrocartilaginous discs between the condyles of the femur and tibia
medial and lateral menisci (sin.=meniscus)
List the four main joints of the hock/tarsus
tibiotarsal joint, proximal intertarsal (PIT) joint, distal intertarsal (DIT) joint, Tarsometatarsal (TMt) joint
List the different types of muscles and whether they are voluntary or not
*striated (skeletal [voluntary])
*cardiac [involuntary]
*smooth (unstriated [involuntary])
What are the two attachments of skeletal muscles?
origin (proximal or usually least movable) and insertion (distal or usually more movable)
What are the flat attachments of flat muscles (eg. abdominal muscles)?
aponeuroses (sin.=aponeurosis)
What is the difference between tendons and ligaments?
Tendons: attaches a muscle to bone; Ligaments: attach 2 bones
What do muscles' actions depend upon? (3)
how they cross a joint, the # of joints crossed, and shape of joints
How is the nervous system divided? a. Functionally? b. structurally?
a. somatic (body) and autonomic (ANS, visceral system) nervous systems
b. Central (CNS) and peripheral nervous systems (PNS)
what functional division of the nervous system keeps the body in balance with its external and internal environment, respectively?
External: somatic
Internal: autonomic (ANS)
what are the two parts of the CNS?
brain and spinal cord
what are the three parts of the PNS?
cranial nerves, spinal nerves, and ganglia
what are the two impulses of the nervous system, both somatic and autonomic?
sensory (afferent) and motor (efferent)
What nervous structures pass from the spinal cord to the periphery?
spinal nerves (LMN, lower motor neurons)
where do the spinal nerves leave the vertebral column?
intervertebral foramen
what arises from the spinal cord to form a spinal nerve?
dorsal (sensory) and ventral (motor) roots
what are the two main branches of spinal nerves? (what do they carry?)
Dorsal and ventral branches, (mixed: motor and sensory fibers).
To what areas do the ventral and dorsal motor branches of the spinal nerves supply motor innervation?
Ventral: muscles ventral to the transverse process of the vertebrae
Dorsal: muscles dorsal to the transverse processes, sensory innervation not exactly the same)
What spinal nerve branches receive sensation from the skin of the abdominal wall and back?
Dorsal: back (above the transverse processes) and upper flank (area just below the transverse processes), Ventral: rest
List the components of a reflex arc
stimulus, receptor, sensory neurons, interneurons, motor neurons, effector organ
What are aggregations of nerve cell bodies in the CNS? PNS?
CNS: nucleus; PNS: ganglion
What is gray matter?
part of nervous tissue consisting of the neuronal cell bodies
What is the white matter?
part of the nervous tissue consisting mainly of myelinated nerve fibers/axons
What is a nerve?
a bundle of nerve processes outside the CNS
what are nerve tracts or fasciculi?
nerve fiber bundles of common origin in the brain and spinal cord
what is the definition of an artery? a vein?
arteries: vessels that travel away from the heart; veins: toward the heart
list the superficial lymph nodes of the body (5)
parotid, mandibular, superficial cervical, popliteal, and superficial inguinal
the skin consists of what two layers?
epidermis and dermis
the two layers of the skin (dermis and epidermis) lie on the ____.
subcutaneous layer, superficial fascia, subcutis; hypodermis, SQ or SC
where is the skin thin? where is it thick?
belly; neck
what is another name for eyelids?
palpebrae
what is the function of the pupil?
control amount of light coming into the eye
what is the flap of skin inside the medial part of the eyelids?
third eyelid (nictitating membrane)
how can you get the third eyelid to cross the eye for examination?
open the palpebral fissure and press the eyeball through the lateral upper lid
how can the mouth be opened to look in the oral cavity?
grasp the upper jaw with one hand and pushing down on the incisors with a finger of the other
what are the large, shearing teeth of dogs and cats?
carnassial or sectorial teeth (upper premolar 4 and lower molar 1)
which teeth have three roots in the dog?
Last three on top (PM4, M1, and M2)
describe the external ear canal.
two parts, vertical part passes down takes a sharp turn and continues as the horizontal part to the ear drum (tympanic membrane)
what is the pocket of skin in the caudal edge of the ear?
cutaneous pouch
what do the costal cartilages of the ribs caudal to the sternum form?
costal arch
what remains of the entrance of the umbilical cord?
umbilicus or belly button (faint scar)
how many mammae does the dog usually have?
8 to 10 or 4 to 5 pairs
what is the lateral abdominal area between the back legs?
inguinal region
what is the most dorsal portion of the flank?
paralumbar fossa
what are the boundaries of the perineum
base of the tail, tuber ischii, past the vulva (female), to base of the scrotum (dog) (past scrotum in cats)
where are the openings of the anal sacs (clock-faced analogy)?
4 and 8 o'clock position
what is the depression on either side of the anus?
ischiorectal fossa
where would you find the tibia and fibula?
crus or true leg (gaskin)
where is the clitoris found?
in the ventral commissure of labia
What is the picture taken by a radiographic machine called?
radiograph or film, not an X-ray
why isn't X-ray an appropriate term for a radiograph/film?
can't see X-rays
what is evaluated in a radiograph?
shape and density
what can eliminate the need to think about the inverse square rule?
using standard distance for different techniques (technique chart) eliminates distance as a variable
how do you minimize the distortion of divergence in radiology?
always place the part/side of interest against the cassette so it will be sharp and close to actual size
how do the five different radiographic densities appear on film?
Air & Fat = black; Water = shades of gray; Bone & Metal = white
what the five B's that aid in remembering density differences?
Bubbles, Blubber, Blood, Bone, Bullet = Air, Fat, Water, Bone, and Metal
what is required to see structures in a radiograph that touch each other?
differences in densities between them
how is fat a friend when reading radiographs
more radiolucent = contrasts soft tissues (e.g., perirenal fat around the kidney)
define the following radiographic terms:
a. increased opacity:
b. decreases opacity:
c. radiolucent:
d. radiopaque:
e. increased radiolucency:
a. whiter shadow than expected caused by an increased subject density or size
b. darker shadow than expected caused by a decrease in the subject density or size
c. dark, a structure allowing most of the X-rays to pass through it, resulting in a dark shadow
d. white, a structure that blocks most of the X-rays resulting in a white shadow
e. darker, caused by decreased density or size of a subject
what is the general rule in preparing the animal to take good radiographs?
minimal amount of movement
discuss minimal amount of movement when taking radiographs
varies with type of radiograph: from minimal restraint, to sedation, or anesthetized(spine films)
what does and does not lead protect against in relationship to radiology?
does: scatter; doesn't: primary beam
what is often imagined in radiographs but can't be seen, as it is a 2D image?
do not try to read or see depth
how are radiographic views named?
where the beam enters and exits the body/part
Describe how the beam enters and exits the body in the following way:
Right or left lateral projections of major body cavities (abdomen, thorax)
named for the surface closest to the cassette (beam exit point).
Describe how the beam enters and exits the body in the following way:
DV/dorsoventral and VD/ventrodorsal projections:
DV: beam enters the dorsal surface and exits ventral. VD: enters ventral surface and exits the dorsal
Describe how the beam enters and exits the body in the following way:
Craniocaudal (CrCa) or anterior/posterior (AP) projections:
CrCa: beam enters cranial/anterior side and exits caudal/posterior surface (back) of the limb above the carpus/tarsus
Describe how the beam enters and exits the body in the following way:
DP/dorsopalmer (dorsoplantar) PD or palmarodorsal (plantarodorsal) projections:
DP: shot from the "front to back" (dorsal to the palmer side) below the proximal end of the carpus (tarsus)
PD: beam through the palmer/plantar side and out the dorsal side below the proximal end of the carpus (tarsus)
what do lead "R" and "L" markers indicate on a radiograph?
Patient's lateral side placed on the film/"down", side of body in VD and DV films, or which limb if there is only one limb in the film
what should always be used to check if markers on a film are correct?
anatomical landmarks
what is the survival law when reading radiographs?
read in a systematic manner
what helps you orient the views and indicate the direction of the beam?
anatomical landmarks
what view silhouettes lateral and medial limb structures?
craniocaudally, dorsopalmar, or dorsoventral
since a radiograph is a 2D representation of a three dimensional object, how is the third dimension extrapolated?
at least two radiographs must be take at 90 degrees to each other
the different views _____ different sides of the bones.
highlight/silhouette
what does the lateral view silhouette?
cranial and caudal surfaces of bones
is cartilage seen radiographically?
no, only inferred
since cartilage can't be seen radiographically, how is it evaluated?
check subchondral bone
what is the space between bones seen in a radiograph?
joint space and articular cartilage
What is the composition of most long bones at birth?
bone capped at both ends with articular cartilage, 2 cartilaginous discs between the diaphysis and the 2 epiphyses
What are the cartilaginous discs between the diaphysis and epiphysis?
epiphyseal, metaphyseal or growth plate; or physis
where does lengthening of bone occur?
epiphyseal side of the metaphyseal plate
during growth, how does the physis appear radiographically?
as a radiolucent line (dark line).
what should not be mistaken for fractures radiographically?
physeal lines or sesamoid bones
what is a normal remnant of the closed physis?
physeal scar
Where are growing long bones prone to fracture?
physis (growth plate)
when do most physes close (by what age?
by one year of age
What is inflammation of a tendon? Tendon sheath?
tendinitis, tendosynovitis/tenosynovitis (tendovaginitis)
what is osteocondrosis (OC)?
a defect in endochondral ossification which causes the deeper layers of articular cartilage to die
what is osteochondrosis dissecans (OCD)?
osteochondrosis with a dissecting flap or separated piece of cartilage ("joint mouse")
what is the most common place for osteochondrosis in dogs?
shoulder; the head of the humerus
do you look for radiographic changes in the cartilage in OC?
no, can't see cartilage, check subchondral bone
List names for inflammation of a joint (5).
arthritis, osteoarthritis, osteoarthrosis, osteoarthropathy, degenerative joint disease
what is an infection in a joint(s) with bacteria, virus and/or fungus that causes cartilage damage?
septic (infections, bacterial) arthritis
DJD stands for what? what are other names for it?
Degenerative joint disease (chronic), also called osteoarthritis, osteoarthrosis, degenerative arthritis
what is luxation or a dislocation?
complete loss of contact between the articular surface of the joint
define a subluxation.
partial loss of contact between the articular surfaces of the joint
why are articular fractures difficult to treat?
must achieve anatomical reduction and rigid skeletal fixation to perfectly align the cartilage surface (no step defect) or it will rapidly lead to DJD
what is inflammation of a bursae?
Bursitis
What is the injection of a substance into a muscle? how is it done?
intramuscular (IM) injection; always draw back on (aspirate) the syringe before injecting to make sure the needle is not a vessel (see blood in the hub if in vessel).
why is knowing the drainage area of lymph nodes and the destination of their efferent vessels important in clinical diagnosis, meat inspection, and necropsy?
lymph node: enlarge in response to infection or the spread of cancer
how can superficial lymph nodes be important clinically?
indicator of an illness (enlarge in response to infection)
why are lymph nodes biopsied?
for lab analysis = valuable diagnostic info in many diseases
what is an ectopic cilia?
misplaced eyelash that may contract and scratch the cornea
what is the capillary refill time (CRT)? what is the normal CRT?
time it takes for the mucosa (ex: gums) blanched by finger pressure to return to a normal pink color. Less than 1-2 seconds.
how is a SQ injection performed?
tent the skin at the junction of the neck and back and slip the needle into the subcutaneous tissue
what is the clinical significance of the umbilicus?
umbilical hernias, surgical landmark
How are anal glands expressed?
thumb in one ischiorectal fossa and fingers in the other. push forward (cranial to anal sacs), squeeze, and pull caudally to express the contents of the sac into a paper towel held in your gloved hand
what is the clinical importance of a prepucial discharge?
usually normal
what happends when dogs' or cats' nails are cut too short
"quicked" = pain and bleeding
what is an onychectomy and how is regrowth prevented?
declaw, dorsal apsect of the ungual crest must be removed
what is it called when one or both testicles do not descend into the scrotum?
Cryptorchidism
List the common venipuncture sites in order of how often they are used.
cephalic (easiest), external jugular (mobile), lateral saphenous (dog) or medial saphenous vein (cat), and lingual (veins)
how do you raise the cephalic vein on a restrained dog?
crus the thumb behind the elbow and index finger over the cranial elbow and pull lateral to straighten out the vein
where is venipuncture usually performed on the cephalic vein
in the forearm above the carpus; start distally so that if you "flub" you can move up the forearm
why is the external jugular vein, which passes superficially up the neck, difficult to perform venipuncture into?
moves freely
to puncture the external jugular vein, first go through the ____ parallel to the vein and then angle and insert the needle gently into the vein
skin
what superficial vein used for venipuncture, travels up the lateral side of the hind limb to disappear behind the stifle?
lateral saphenous vein
what vein in the head can be punctured during surgery, when other vessels are not accessible?
lingual vein
a structure closer to or further from the median plane is ___ or ___, respectively.
medial or lateral
a part is ___ if it is in front of another part or closer to the head
cranial
what head term corresponds to "cranial" in the rest of the body?
rostral
what is a part closer to the tail or farther from the head?
caudal
for what is the term dorsal used?
the surface of the body away from the ground and below the proximal carpus and tarsus directed toward the head
what surface of the body faces the ground?
ventral
what is the name of the surface opposite the palmer/plantar surface?
dorsal
what is the term used for a part closer to or farther from a point of attachment or to the trunk, respectively?
proximal or distal
the body is divided into dorsal and ventral portions by a ___ plane.
dorsal (frontal) plane
What are sections?
cuts through the planes of the body
a ___ plane cuts an organ or limb at a right angle to its long axis. these are usually called ___ ____.
transverse/cross sections
What section cuts through a transverse plane.
cross section
what section cuts parallel to the long axis of an organ or limb?
longitudinal section
the human term "anterior" corresponds with what veterinary terms?
cranial on limbs, rostral on face, and ventral on body
where are "superior" and "inferior" used in veterinary medicine?
for the eyes and a few other head structures, replacing dorsal and ventral, respectively
the human term "posterior" corresponds with ___ and ____.
caudal (limbs and head); dorsal (body)
give an example of each type of bone according to shape?
short (carpal), flat (most facial bones), irregular (vertebral), sesamoid (patella), long (humerus)
what is the smooth layer of hyaline cartilage over the joint ends of bones?
articular cartilage
what is the space in the diaphysis containing the marrow?
medullary cavity
what is the fibrous and cellular tissue lining the medullary cavity of a bone?
endosteum
what is an apophysis?
any outgrowth of a bone
what are spicules of bone separated by spaces in cancellous bone?
trabeculae
what is any prominent, roughened projected from a bone?
process
what is a large, kuckle-like articular prominence?
condyle
a ___ is a tube-like canal through a bone.
Meatus
what is a smooth, flat, articular surface?
facet/fovea
what is the pulley-shaped structure of the femur?
trochlea
what is a prominence above a condyle?
epicondyle
a ___ is an opening through a bone
foramen
list the bones and cartilages of the axial skeleton
skull w/mandible, hyoid apparatus, vertebral column or backbone (CTLSC), bony thorax (ribs, sternum)
what is the appendicular skeleton?
consists of the bones of the limbs
list the bones of the thoracic limb (pectoral limb and forelimb)
clavicle (cat), scapula, humerus, radius, ulna, carpal bones (radial carpal, accessory carpal), metacarpals, digital bones (proximal phalanx, middle phalanx, distal phalanx, sesamoids)
list the bones of the pelvic limb or hind limb
bony pelvis (hip bone or ossa coxae [ilium, pubis, ischium]) femur, patella, tibia, fibular, tarsal bones (calcaneus, talus) metatarsal bones, digit bones (P1, P2, P3)
how are synovial joints classified by their number of articular surfaces?
into simple or compound
give an example of a compound joint
stifle, elbow
a ____ or ___ joint allows flexion and extension.
ginglymus or hinge
give examples of a hinge joint?
elbow, proximal interphalangeal joint
what type of motion does a plane joint allow?
simple gliding or sliding motion
give examples of a plane joint.
carpal, small tarsal bones, cranial and caudal articulations between vertebrae
what type of synovial joint allows universal movement?
ball-and-socket/spheroidal
give examples of a ball-and-socket joint
shoulder and hip joints
what is an uniaxial joint allowing rotation around a longitudinal axis of a bone?
pivot joint
give an example of a pivot joint
atlantoaxial joint, proximal radioulnar joint
what uniaxial joint is formed by two condyles of one bone fitting into concavities of another bone?
condylar joint
give an example of a condylar joint.
stifle, atlanto-occipital
what type of action is permitted by a condylar joint.
flexion and extension and a little rotation
what structural type of join is characterized by its mobility?
synovial
of what does the joint capsule of a synovial joint consist?
out fibrous layer and inner synovial layer (membrane)
what lubricating, viscous fluid is produced by synovial membranes?
synovial fluid
what is the function of the articular cartilage?
reduces concussion and friction effects
what supplies the nutrients and removes waste from hyaline cartilage?
synovial fluid
what are the strong bands of white fibrous tissue uniting bones?
ligaments
what plate of fibrocartilage partially or completely divides the joint cavity of the stifle and temporomandibular joint?
meniscus or disc
what sac-like structure is found between different tissues?
bursa
what muscle types are involuntary?
smooth and cardiac
what type of muscles are voluntary?
skeletal
what are the two attachments of skeletal muscles?
origin and insertion
what is the origin of a muscle?
proximal or usually least movable attachment
what is the insertion of a muscle?
distal or usually more movable attachment
which attachment is the origin for the extrinsic limb muscles and the muscles of the rest of the body?
least movable
what attaches muscle to a bone?
tendon running through the entire muscle
what structure attaches two bones?
ligament
what type of muscle's fibers encircle an opening?
sphincter
muscles having the same action on a joint will generally be innervated by the ___ nerve.
same
how do muscles work mechanically?
by pulling, not pushing
in anatomy how does the length of a name compare to the importance of a structure?
longer the name, less important
define extension and flexion
extension: increases angle between two bones
flexion: decreases angle
define movement of adduction and abduction
ADduction: toward (adds to) body; ABduction: away from body
define supination and pronation
supination: palmar surface dorsal; pronation: palmar surface ventral
rotation is movement of a part around its ___ axis.
longitudinal axis
what is movement of an extremity in a plane describing the surface of a cone?
circumduction
what motion moves a part forward? returning a protracted part to its usual position?
protraction; retraction
what motion bends the spinal column dorsally or ventrally?
dorsal or ventral flexion
what are two components of nervous tissue?
neurons or nerve cells; neuroglia cells
list the parts of the neuron or nerve cell
cell body: the control center; Nucleus; nerve processes: two types extend from the cell: dendrites (receptor), axon; synaptic knobs
give an example of a central and a peripheral neuroglia
CNS: astrocytes, oligodendrocytes, and microglia
PNS: Schwann cells
Discuss Schwann cells
neuroglia of the PNS that form myelin sheaths by winding around nerve processes. myelin is a lipoprotein forming a sheath around nerve processes that function to increase the speed of impulse conduction and to insulate the nerve process. Nodes of Ranvier are unmyelinated gaps between segments of myelin sheath
Define a synapes
a specialized site of apposition where information passes from one nerve cell to another cell
describe the components of a synapse
1st cell: presynaptic cell (always nerve), 2nd: postsynaptic cell (neuron, a muscle, or gland) with synaptic cleft between
Describe a synaptic event
NAP propagates down axon to synaptic knob of presynaptic cell, causing synaptic vesicles to release neurotransmitters into cleft. they then diffuse across the cleft to bind receptors on postsynaptic membrane causing a change in the membrane. if the postsynaptic cell is a neuron, the event can initiate or inhibit another NAP .
what type of nerve fibers pass through dorsal and ventral roots?
dorsal: sensory; ventral: motor
which root of a spinal nerve brings sensory fibers to the spinal cord
dorsal root
what is the swelling of the dorsal root? what causes the swelling?
dorsal root ganglia, -cell bodies of sensory fibers
what spinal root carries motor nerve fibers from cell bodies in the spinal cord to muscle and glands?
ventral root
describe components of a reflex arc
stimulus: a change in environment
receptor: sensory neuron's dendritic zone; generates NAP
sensory (afferent) neuron: carries sensory impulses to CNS
interneuron: connects sensory with motor
Motor: carries impulse to effector organ
Effector organ (target): muscle or gland innervated by motor neuron reacts to stimulus
what makes up the lymphatic system?
lymphatic tissues and vessels (lymph, lymph nodes, tonsils, spleen, thymus)
describe lymphatic vessels
similar to veins, bit thinner walls, more valves, and lymph nodes along their course
describe typical lymph node
bean-shaped encapsulated lymphoid tissue scattered along the course of the medium-sized lymphatic vessels
list the superficial lymph nodes of the body and locations
parotid lymph node (below ear); mandibular lymph nodes (near the angle of mandible);
what is another name for the skin?
common integument, cutis
name three structures consisting of common integument
sweat glands, skin, claws, hoof, horn, hair
why is the skin thick on the neck?
to protect the external jugular vein
what are the long filamentous appendages of skin?
hair
how does the epidermis receive nutrition
blood vessels or vibrissae
where are tactile hairs found?
above the eyes, on muzzle, behind carpus
what are the upper and lower eyelids called, respectively?
superior and inferior palpebrae
what is the opening surrounded by the eyelids?
palpebral fissure
what is the clear rostral part of the eyeball?
cornea
list three functions of the cornea?
physical barrier, let light into the eye, refract the light
what is the colored part of the eye?
iris
what is the void in the center of the iris?
pupil
how does the third eyelid protect the eye?
covers eye when eyeball is retracted
what is the general structure rostral to the eyes called?
muzzle
what is the groove in the upper lip and between the nostrils?
philtrum
what are functions of the teeth in dogs?
weapons and prehensile tools
how do dogs eat their food?
grasp, tear, and gulp with little mastication
list the types of teeth and their abbrev.
Incisors (I), canines (C), cheek teeth, premolars (Pm, P), molars (M)
what is the muscular organ filling the oral cavity that's used for prehension and lapping up fluid?
tongue
what is the tissue surrounding the neck of teeth?
gums
the ears can be directed to sounds ___ of each other.
independent
what is the flap of cartilage and skin of the visible part of the ear?
pinna
of what does the bony thorax consist?
thoracic vertebrae, ribs, sternum
what is formed by the sternebrae on the ventral surface of the chest?
sternum
name the cranial most sternebrae
manubrium
what is the caudal end of the sternum which is made of cartilage.
xiphoid process
name the last rib on each side not attached to the costal arch
free or floating rib (dog)
where do you palpate the floating ribs on the standing dog?
caudal and dorsal to the costal arch
what are the mammary glands of the dog called?
mammae
list the mammae of the dog
2 pairs: thoracic; 2 pairs: abdominal, and 1 pair; inguinal
what is the base of the tail on the top line of the body called?
tail head
what is the perineum?
closes the pelvic outlet around the terminal parts of the urogenital and digestive tracts
what does the external perineum, or perineal region, include?
anus and vulva in female to just above scrotum in dog
what are the boundaries of the perineum?
base of the tail: dorsal; tuber ischii: lateral; past vulve in female and to base of scrotum in male
what is the exit of the GI tract located right below the tail?
anus
where are the specific openings of the anal sacs?
mucocutaneous junctions at the 4 and 8 o'clock position
what is the sac-like appendage housing the testicles?
scrotum
what is one or both testicles not descending into the scrotum called?
cryptorchidism
what is the sheath of skin covering the penis?
prepuce
what is the external genitalia of the female?
vulva
what is the female counterpart to the scrotum?
labia
what is the proper name of the arm pit?
axilla
what is the proper name of the arm?
brachium
with what is the word brachium easy to confuse?
brachy (meaning short)
what is the proper name of the forearm?
antebrachium
what structure does the carpus, metacarpus, and digits compose?
manus
what is the area between the back legs on the stomach?
inguinal region
where would you find the tibia and fibula?
crus (true leg)
what is the distal part of the hind limb consisting of the tarsus, metatarsus and digits called? what does it correspond to in humans?
pes, the human foot
what is the common name for the tarsus (ankle in humans)?
hock
what tough, thickened common integument does a dog walk on?
foot pads
man is plantigrade, what are dogs?
digitigrade
what does digitigrade mean?
stand on their digits
what is the thickening over the palmer surface of the carpus?
carpal pad
what is the very large, single, triangular-shaped pad palmar to the metacarpo/metatarsophalangeal junction?
metacarpal/metatarsal pad
what are the pads on the distal end of each digit?
digital pads
name the rudimentary first digits on the fore- and sometimes hind limbs.
dew claws
which limbs are more likely to have dew claws?
forelimbs
what are the spaces between the digits
interdigital spaces
what is the modified epidermis enclosing the dog's ungual process.
claw
name the toughest skin of carnivores.
pads
when is radiology, as a diagnostic modality, selected?
when the history and physical exam suggests a possible benefit
although radiology seldom yields a final diagnosis, how does it contribute?
creation of adequate differential diagnoses lists
how is the visible image (radiograph) created?
passage of ionizing radiation through body, interaction of escaped radiation with intensifying screens, action of subsequent emitted light with film and effect of developing chemicals
a radiograph is basically a negative; therefore, the lighter or darker the film is tells us what?
lighter=more under-exposed, darker=more over-exposed
how does the radiograph (x-ray) machine create a directed beam of electrodes?
passes electr. from a cathode through a vacuum to hit the anode, giving off x-rays (photons) as a beam and creating heat. beam leaves lead box through shuttered opening
describe a radiograph cassette
holds radiograph film sandwiched between intensifying screens
how is object to be radiographed placed in relationship to the x-ray machine and the cassette?
placed on the cassette between it and the tube head
what is the part of the x-ray machine allowing restriction of the size of the beam leaving the machine?
the collimator
describe a radiograph film
a piece of plastic with bilayer of silver halide emulsion
how does the silver halide emulsion on a radiographic film react with x-ray or light and become a radiograph?
X-ray/light activates silver halide. developer crystallizes activated silver, which appears black, sticks to plastic. fixer clears unreacted silver halide leaving only plastic film
what is a fluorescent light source for viewing radiographs?
viewer
what is a strong source of light placed behind the film to view over-exposed area (darker than desired)?
spotlight or hot light
what are the three things that can happen to the part of the beam hitting the object?
scatter, absorption, further transmission
what is scatter?
reflection: the redirection of a percentage of the primary beam striking an object's surface
what affects penetration or transmittance?
both the object's thickness and density
what is the inverse square law?
increase distance = 1/4 power
what is divergence in relationship to radiology?
spreading the primary beam or scatter as it moves away from the source
because of divergence in radiology, how does placement on the cassette affect the radiograph?
closer the object to cassette, the less divergence, thus the smaller and sharper the image
what is radiographic opacity?
degree of whitening of a film caused by x-rays blocked passing through a part
what determines a part's radiographic density?
part's density and thickness
is an underexposed or an over exposed film better? why?
overexposed is better. it may still be imaged and may be seen with a spotlight.
what is denser fat or water?
water (fat floats)
what are the water densities seen in radiographs?
soft tissue densities, all appear similar not easily distinguished
how does the heart appear radiographically? why?
sold gray shadow disc, as fluid-filled ventricles not demarcated from the soft tissue walls
can blood, urine, chyle, exudates, and transudates be distinguished from each other radiographically?
no
what can cause a darker shadow than expected on a radiograph?
decrease in subject density or its size
what is a structure that allows most of the X-rays to pass through it, resulting in a dark shadow on the film?
radiolucent (dark)
what type of structure blocks most of the X-rays resulting in a white shadow on the film?
radiopaque (white)
what identification does a film need in addition to "R" and "L" markers?
label identifying client, animal, date, facility performing student; and if a timed study, the time elapsed after procedure started
what can be used to properly place the animal in relation to the beam direction without having to use people?
sand bags and positioning devices
some studies, such as abdominal radiographs, are compromised by food and fecal material in the GI tract. what preparation should be done in these cases?
withhold food for 12 hours prior to radiograph and perhaps using an enema
what are artifacts (def: made by human hand) on radiographs?
not part of the animal, ex: dirt, wet hair, ointments
what can be done to minimize artifacts on radiographs?
clean the animal first and take care with films
what should be foremost in your mind wherever radiographing?
safety
although invisible, X-rays are very dangerous and additive over time, so the general rule is?
never place any part of your body in the primary beam, wear lead aprons, gloves, and stand behind lead shield if possible to block scatter
to maximize safety, what is the rule about primary beam?
always collimated to no larger than the size of the cassette or region
how is the beam direction used for naming radiographic views?
first passes into the body or part, followed by where it exits the body or body part to reach the film
how do films shot from an opposite direction look?
difficult to differentiate without markers. a caudal/cranial and a cranial/caudal view will look identical in small animals because radiographs have no depth.
How is a lateral medial (LM) view taken?
Beam enters the lateral side and leaves the medial side.
How are caudocranial (CaCr) or posterior/anterior (PA) taken?
Beam enters caudal/posterior/side and exits cranial/anterior of limb above the carpus/tarsus.
How are lateral body cavity films named?
named for where the beam exits the body: animal in left lateral recumbency (right side up, left side down) = left lateral projection
what is the survival law when reading radiographs?
read in systematic manner. Do not miss something important by jumping at the most obvious
What is the first thing to determine when reading a radiograph?
determine what region is radiographed
what type of knowledge is essential to reading radiographic films?
knowing the anatomy
what does "silhouetted" mean when discussing bone radiographs?
edges of a structure are contrasted against air or soft tissue
list two structures that are silhouetted in a dorsopalmer view of the carpus
radial bone [lateral structure] and ulnar carpal bone [medial structure]
what bony structures are silhouetted in a ventrodorsal view?
lateral edges of the ribs (lateral structures)
what view silhouettes caudal and cranial limb structures?
lateromedially or mediolaterally
what structures are silhouetted by craniocaudally, dorsopalmer, or dorsoventral beam direction?
lateral and medial structures
silhouetted caudal and cranial structures indicate the beam was directed how?
lateromedially or mediolaterally
what is the checklist method of reading radiographic films?
do not look at the lines, grays, and shadows to identify the anatomic structures but work from a list of the structures in a specific order
why is a checklist used to read films?
doesn't "miss" agensis (absence) of an organ
how are physeal fractures classified? why?
salter or salter-harris
What is the most common type of physeal fracture?
SH type 2
what physeal fractures have a good prognosis?
type 1 and 2
what are broken bones called and when do they heal in young and old animals?
fractures: young: 4-6 weeks, old: 8 weeks
healing of a fracture begins with the formation of a ____.
callus
what can look radiologically identical to osteomyelitis?
bone tumors/osteosarcoma (irregular sunburst appearance)
how do you differentiate radiographically-identical bone infections or tumors?
a bone biopsy and culture
what is the #1 bone tumor in small animals?
osteosarcoma
what characterizes an early osteosarcoma? what does it necessitate?
early metastasizes so chest radiographs needed. radiology shows rough and irregularly sunburst appearance
what is inflammation of a tendon without involvement of the tendon sheath?
tendinitis
what is inflammation of a tendon sheath?
tendosynovitis/tenosynovitis
what is the bulging of the sheath due to a pathological increase in synovial fluid?
hygroma of the tendon sheath
why does the amount of fluid present indicate the state of health of a joint?
minimal in the healthy animal
arthritis
inflammation of a joint
arthropathy
any joint disease
polyarthritis
inflammation of several joints
osteitis
inflammation of bone; osteomyelitis
osteomyelitis
inflammation of bone; osteitis
osteoarthritis
noninflammatory DJD
osteoarthrosis
chronic DJD
osteoarthropathy
any disease of joint and bones
what is an infection in a joint with bacteria, virus and/or fungus that causes cartilage damage?
septic arthritis
define DJD
progressive deterioration of articular cartilage due to many causes like trauma, age
how does DJD start?
synovitis: results in progressive degradation of cartilage
how does DJD appear radiographically?
marginal osteophyte formation is the hallmark, subchondral bone sclerosis or irregularity, and narrowing of joint space
what is an unhealed fracture, having all structures of a synovial joint?
false joint
what is an articular fracture?
fracture that passes through the articular cartilage
what are to types of angular limb deformities
valgus and varus
Lymph nodes ___ the lymph passing through them
filter
why are lymph nodes important indicators of infection?
respond to pathogens they filter by enlarging
why is care taken when evaluating enlargement of lymph nodes?
large variations in size between individuals and even sides of the same animal