anat & phys

Anatomy (def)

The scientific study of the structure of the body (shape/location/connection)

Physiology (def)

The scientific study of how the body functions (what does it do? how does it do it?)

Levels of body organization

Cells → Tissues → Organs → Body system → Organism

The cell

The basic structural and functional unit of the body

Taxonomy (def)

The science of classifying organisms into groups based on similarities in evolution, structure, and behavior

Taxonomic hierarchy (top to bottom)

Kingdom → Phylum → Class → Order → Family → Genus → Species

Two broad animal divisions

Vertebrates & Invertebrates

Vertebrate classes of veterinary importance

Amphibia, Reptilia, Aves (birds), Fish, Mammalia

Structural systems (def)

Body systems that provide the body's basic framework and transport system (skeletal, muscular, integument, cardiovascular)

Coordinating systems (def)

Body systems that control and coordinate body functions (nervous, endocrine)

Visceral systems (def)

Body systems that perform major internal functions, located within body cavities (digestive, respiratory, urinary, reproductive)

Skeletal system function

Provides the supporting framework

Muscular system function

Moves the skeleton to produce locomotion

Integument function

Forms the external covering of the body (skin and hair)

Cardiovascular system function

Transports blood throughout the body

Nervous system function

Carries info to/from the brain; monitors internal/external environments

Endocrine system function

Regulates body functions via chemical messengers called hormones

Digestive system function

Breaks food into components usable by the body

Respiratory system function

Takes in oxygen and removes carbon dioxide

Urinary system function

Eliminates waste and toxic substances

Plasma (body fluid)

Intravascular fluid — 5% of total body weight (TBW)

Interstitial fluid

Fluid surrounding cells — 15% of TBW

Intracellular fluid

Fluid within cells — 50% of TBW

Edema

Abnormal accumulation of fluid in the interstitial space

Homeostasis (def)

The process by which an organism maintains a stable internal environment despite external changes, via negative feedback loops

Allostasis (def)

Achieving stability through change — the body adapts to stressors by altering set points or activating different physiological systems

Negative feedback (def)

A control mechanism that counteracts a change, bringing the system back to its set point (Sensors → Integrator → Effectors → Homeostasis)

Positive feedback (def)

A control mechanism that amplifies a change, moving the system further from its starting point

Cell membrane (def)

Separates the cell from its environment; regulates movement of substances into/out of the cell

`Cytoplasm (def)

Internal fluid that supports and contains cellular structures

Nucleus (def)

Contains chromosomes and hereditary material (DNA)

Mitochondria function

Energy (ATP) production

The 4 primary tissue types

Epithelial, Connective, Muscle, Nervous

Epithelial tissue function

Protection, absorption, secretion, filtration

Epithelial classification systems

By shape of cells (squamous, cuboidal, columnar) AND by number of layers (simple, stratified, pseudostratified)

Squamous cells

Flattened cells; used where a thin layer is needed

Cuboidal cells

Cube-shaped; can produce secretion

Columnar cells

Column-shaped; for secretion and/or absorption

Simple epithelium

Single layer of cells; for absorption or exchange

Stratified epithelium

Several layers of cells with different shapes; suited for protection

Pseudostratified epithelium

Falsely appears layered because stacked cells are all touching the basement membrane in one true layer

Goblet cells

Unicellular glands within epithelium that secrete mucus

Glandular epithelium (def)

Specialized epithelial tissue adapted for secretion (mucus, enzymes, hormones, sweat, milk, sebum, digestive juices)

Exocrine glands

Possess ducts; secrete onto an epithelial surface or into a body cavity (e.g., salivary, sweat, sebaceous, mammary, exocrine pancreas)

Endocrine glands

Ductless; release hormones directly into blood/lymph; highly vascular (e.g., thyroid, adrenal, pituitary, parathyroid)

Anterior

Toward the front; belly side in humans/bipeds (differs in quadrupeds)

Posterior

Further back, nearer the tail (used mainly in humans/bipeds)

Ventral

The underside of an animal (quadruped, fish, or snake); e.g., intestines are ventral to kidneys

Dorsal

The back/upper surface of an animal; e.g., kidneys are dorsal to intestines

Cranial (Superior in humans)

Toward the head; e.g., lungs are cranial to the intestines

Caudal (Inferior in humans)

Toward the tail; e.g., intestines are caudal to the lungs

Rostral

Toward the nose, within the head; e.g., cerebrum is rostral to the cerebellum

Proximal

Nearest the trunk of the body or point of origin; e.g., shoulder is proximal to the elbow

Distal

Further from the point of attachment; e.g., foot is distal to the knee

Superficial/external

Near or closer to the surface; e.g., skin is superficial

Deep/internal

Further from the body's surface; e.g., a fish's stomach is deep compared to its gills

Medial

Toward the median plane/midline; e.g., heart is medial to the lungs

Lateral

Further away from the midline; e.g., ribs are lateral to the lungs

Palmar

Caudal surface of the forelimb (the "palm")

Plantar

Caudal surface of the hind limb (the "sole")

Ipsilateral

Structures on the same side of the body

Contralateral

Structures on opposite sides of the body

Bilateral

Paired structures on right and left sides

Unilateral

Structure found on only one side of the body

Sinistral

Left

Dextral

Right

Oculus

eye

auris

ear

Median plane

Passes through the body cranio-caudally; divides it into equal left and right halves (also called midsagittal)

Sagittal plane

Parallel to the median plane, either to the right or left (not necessarily equal halves)

Transverse plane

Horizontal plane perpendicular to median and sagittal planes; divides the body into cranial/caudal sections

Horizontal/frontal plane

Parallel to the ground; divides a quadruped into dorsal and ventral sections

Prone

Dorsal aspect of the body (or extremity) is uppermost

Supine

Ventral aspect of the body (or palmar/plantar aspect) is uppermost

Cervical vertebrae

Neck region — all mammals have 7

Thoracic vertebrae

Where the ribs attach

Thoracic (region)

chest

Lumbar vertebrae

Lower part of the back

Sacral vertebrae

At the base of the last lumbar vertebrae; fuse to form the sacrum (pelvis)

Sacral (region)

The area between the hips

Orbital

The bony eye socket (orbit)

Cephalic

Of, in, or relating to the head

Femoral

Relating to the femur (thigh bone)

Patellar

The anterior knee (kneecap) region

Crus

From the knee to the ankle

Tibia

The larger shinbone

Gastrocnemius

The major muscle in the back of the crus (the calf)

Tarsus

Heel/ankle — multiple bones between the crus and the rest of the foot

Digitigrade

Walking on the toes (e.g., cats)

Plantigrade

Walking on the soles of the feet (e.g., humans)

Ungulates

Animals with hooves at the ends of their toes

Manus

The hand

Digital

Fingers or toes

Inguinal

The groin

Labia

The lips (mouth and female reproductive tract)

Umbilical

The navel

Occipital

The posterior aspect of the head or base of the skull

Scapular

The scapula/shoulder blade area

Prefix: macro-, mega(lo)-

Large

Prefix: micro-

Small