Medical Terminology and Body Systems Review

Introduction to Medical Terminology and Word Construction

Medical terminology is defined as the language of the medical profession, serving as a standardized method of communication among healthcare providers. The foundation of this language involves the use of root words, combining vowels, prefixes, and suffixes to create specific meanings. Combining vowels, such as the "o" in bio, are the in-between sounds that help connect and pronounce medical terms effectively.

Root words and combining forms designate the core meaning of a term. Key examples include: Albin/oAlbin/o for white; Bi/oBi/o for life; Cry/oCry/o for cold; Cutane/oCutane/o, Derm/oDerm/o, and Dermat/oDermat/o for skin; Cyan/oCyan/o for blue; Diaphor/oDiaphor/o for profuse sweating; Electr/oElectr/o for electricity; Ichthy/oIchthy/o for scaly; Kerat/oKerat/o for hard; Lip/oLip/o for fat; Melan/oMelan/o for black; Myc/oMyc/o for fungus; Necr/oNecr/o for death; Pil/oPil/o for hair; Py/oPy/o for pus; Rhytid/oRhytid/o for wrinkle; Seb/oSeb/o for oil; and Ungu/oUngu/o for nail.

Suffixes are attached at the end of a root word to modify its meaning. Fundamental medical suffixes include: −algia-algia (pain, such as gastralgia for stomach pain); −cele-cele (hernia or protrusion, such as cystocele for bladder protrusion); −cise-cise (cut, like excise to cut out); −cyte-cyte (cell, like erythrocyte for red cell); −dynia-dynia (pain, like cardiodynia for heart pain); −ectasis-ectasis (dilation, as in bronchiectasis); −gen-gen (that which produces, like mutagen); −genesis-genesis (produces or generates, such as osteogenesis); −genic-genic (produces or produced by, like carcinogenic); −ia-ia (state or condition, such as hemegia for being half paralyzed); −iasis-iasis (abnormal condition, like lithiasis for stones); −ism-ism (state of, like hypothyroidism); −itis-itis (inflammation, like cellulitis); −logist-logist (one who studies, like cardiologist); −logy-logy (the study of, like cardiology); −lysis-lysis (destruction, like osteolysis); −malacia-malacia (abnormal softening, like chondromalacia); −megaly-megaly (enlargement, like cardiomegaly); −oma-oma (tumor or mass, like carcinoma); −osis-osis (abnormal condition, like cyanosis); −pathy-pathy (disease, like myopathy); −plasia-plasia (development or growth, like dysplasia); −plasm-plasm (formation or development, like neoplasm); −ptosis-ptosis (drooping, like proctoptosis); −rrhage-rrhage (excessive or abnormal flow, like hemorrhage); −rrhea-rrhea (discharge or flow, like rhinorrhea); −rrhexis-rrhexis (rupture, like hysterorrhexis); −sclerosis-sclerosis (hardening, like arteriosclerosis); −stenosis-stenosis (narrowing, like angiostenosis); −therapy-therapy (treatment, like chemotherapy); and −trophy-trophy (nourishment or development, like hypertrophy).

Prefixes are added to the beginning of root words to expand on location, frequency, number, color, or negative status. Significant prefixes include: A−A- or An−An- (without or away from, like aphasia or anoxia); Ante−Ante- (before or in front of, like anteparturn); Anti−Anti- (against, like antibiotic); Auto−Auto- (self, like autograft); Brady−Brady- (slow, like bradycardia); Dys−Dys- (painful or difficult, like dyspnea); Endo−Endo- (within or inner, like endoscope); Epi−Epi- (upon or over, like epigastric); Eu−Eu- (normal or good, like epunea); Hetero−Hetero- (different, like heterograft); Homo−Homo- (same, like homozygous); Hyper−Hyper- (over or above); Hypo−Hypo- (under or below, like hupoglossal); Infra−Infra- (under, beneath, or below, like infrorbital); Inter−Inter- (among or between, like intervertebral); Intra−Intra- (within or inside, like intravenous); Macro−Macro- (large, like macrocophalic); Micro−Micro- (small, like microcephalic); Neo−Neo- (new, like neonate); Pan−Pan- (all, like pancarditis); Para−Para- (beside, beyond, or near, like paranasal); Per−Per- (through, like percutaneous); Peri−Peri- (around, like pericardial); Post−Post- (after, like postpartum); Pre−Pre- (before or in front of, like prefrontal); Pseudo−Pseudo- (false, like pseudocyesis); Retero−Retero- (backwards or behind, like retrograde); Sub−Sub- (below or under, like subcutaneous); Super−Super- (above or excess, like supernumerary); Supra−Supra- (above, like suprapubic); Tachy−Tachy- (rapid or fast, like tachycardia); Trans−Trans- (through or across, like transurethral); and Ultra−Ultra- (beyond or excess, like ultra sound).

Rules for Creating Plural Medical Forms

Medical terms follow specific linguistic rules for pluralization based on their endings. In English medical terminology, if a word ends in −a-a, keep the −a-a and add −e-e (vertebravertebra becomes vertebraevertebrae). If it ends in −ax-ax, remove the −x-x and add −ces-ces (thoraxthorax becomes thoracesthoraces). If it ends in −ex-ex, drop −ex-ex and add −ices-ices (apexapex becomes apicesapices). If it ends in −ix-ix, drop −x-x and add −ces-ces (appendixappendix becomes appendicesappendices). If it ends in −ma-ma, keep −ma-ma and add −ta-ta (sarcomasarcoma becomes sarcomatasarcomata).

Additional pluralization rules include: words ending in −is-is drop −is-is and add −es-es (metastasismetastasis becomes metastasesmetastases). Words ending in −on-on drop −on-on and add −a-a (spermatozoonspermatozoon becomes spermatozoaspermatozoa). Words ending in −us-us drop −us-us and add −i-i (alveolusalveolus becomes alveolialveoli). Words ending in −um-um drop −um-um and add −a-a (ovumovum becomes ovaova). Words ending in −y-y drop the −y-y and add −ies-ies (biopsybiopsy becomes biopsiesbiopsies). Finally, words ending in −x-x drop the −x-x and add −ges-ges (phalanxphalanx becomes phalangesphalanges).

Anatomical Terminology and Body Orientation

The anatomical position is the standardized reference for body orientation, defined as standing erect, facing forward, with the palms of the hands facing forward and thumbs pointing outward. Directional terms describe the relative positions of structures: anterior refers to the front surface, posterior to the back side, superior to a position above another structure, and inferior to a position below. Medial pertains to the middle, while lateral pertains to the side. Ipsilateral indicates the same side of the body, whereas contralateral refers to the opposite side. Proximal means near the point of attachment to the trunk, and distal refers to being farther away from the attachment point. The apex is the tip or summit of an organ, and the base is the bottom. Deep indicates a position away from the surface, while superficial is on the surface. Prone refers to lying on the belly, and supine refers to lying on the back.

Body movements are described using specific terms: flexion is the bending of a joint in the sagittal plane, and extension is straightening the joint in the same plane. Abduction is moving away from the median plane in the coronal plane, while adduction is moving toward the medial plane. Lateral flexion is the movement of the spine in the coronal plane. Depression is downward movement, and elevation is upward movement. Supination involves movements of the forearm with the palm facing upward, while pronation involves the palm facing backward. Protraction is moving toward the front (anteriorly), and retraction is moving toward the back (posteriorly).

Body Planes, Cavities, and Regions

The body is divided by imaginary lines called planes. The frontal plane (or coronal plane) divides the body vertically into anterior and posterior portions. The sagittal plane (or lateral plane) divides the body into left and right sides. The transverse plane (or cross-section) creates upper and lower sections.

Regional terms identify specific areas: abdominal is the center anterior trunk; brachial is the arm; cephalic is the head; cervical is the neck; crural is the lower extremity; dorsum is the posterior back region; gluteal is the buttocks; pelvic is the lower anterior trunk; pubic is the genital region; thoracic is the chest; trunk is the torso; and vertebral is the spinal column region.

Body cavities are empty spaces containing organs. The two major cavities are the dorsal and ventral cavities. The dorsal cavity is subdivided into the cranial cavity (formed by the skull to protect the brain) and the spinal cavity (vertebral canal protecting the spinal cord). The ventral cavity is lined by a serous membrane to reduce friction, secreting serous fluid. In the thoracic section, the outer membrane layer is the parietal pleura and the inner is the visceral pleura. The thoracic cavity contains the two pleural cavities (each with a lung), the pericardial cavity (housing the heart medial to the pleural cavities), and the mediastinum (containing the esophagus, trachea, thymus gland, aorta, and inferior venae cavae).

The abdominopelvic cavity is divided into the abdominal and pelvic cavities, lined by a two-layer membrane called the peritoneum (outer parietal and inner visceral). The abdominal cavity contains the stomach, spleen, liver, gallbladder, pancreas, and most of the small intestine and colon. The pelvic cavity holds the urinary bladder, ureters, urethra, reproductive organs, and parts of the large and small intestines.

Clinical divisions of the abdominal cavity include four quadrants: the Right Upper Quadrant (RUQ), containing most of the liver, gallbladder, and part of the pancreas/kidney; the Left Upper Quadrant (LUQ), containing the spleen, stomach, and majority of the pancreas; the Right Lower Quadrant (RLQ), containing the appendix and right ovary/ureter; and the Left Lower Quadrant (LLQ), containing the left ovary and ureter. Anatomical divisions include nine regions: Right Hypochondriac, Epigastric, Left Hypochondriac, Right Lumbar, Umbilical, Left Lumbar, Hypogastric, Left Iliac, and Right Iliac.

The Integumentary System

The hierarchy of human biology begins with cells, which form tissues; tissues create organs; and organs work together to form organ systems. The integumentary system includes the skin, hair, nails, sweat glands, sebaceous glands, and nerve receptors. The study of skin is dermatology, and it consists of three layers: the epidermis, the dermis, and the subcutaneous layer (which includes a large layer of fat). The skin serves functions including waterproofing, protection from pathogens, touch sensation, vitamin D synthesis, lubrication, and temperature regulation.

Common diseases include sebaceous gland conditions like acne vulgaris (chronic inflammation caused by sebum overproduction during puberty), seborrhea (overactivity resulting in excessive sebum), and seborrheic keratosis (waxy benign growths in the elderly). Nail conditions include onychia (nail bed inflammation causing nail loss), onychocryptosis (ingrown nail), and onychomycosis (fungal infection). Skin infections include mycosis, tinea (ringworm), impetigo (contagious bacterial infection with crusted pustules), and gangrene (tissue death from loss of circulation).

Surface lesions include maculae (flat spots less than 1 cm1\,\text{cm}), nodules (solid lesions larger than 0.5 cm0.5\,\text{cm}), and weals (smooth, elevated swollen areas). Pigmentation disorders include albinism (absence of pigment), chloasma (pregnancy-related brown spots), and vitiligo (destruction of melanocytes causing white patches). Hair conditions include alopecia (baldness), folliculitis (follicle inflammation), and hirsutism (excessive male-pattern hair in women). Vascular issues under the skin include contusions (discoloration without skin break), ecchymosis (bruising), and petechia (small hemorrhages less than 2 mm2\,\text{mm}).

The Muscular System

Muscles are composed of muscle fibers (myofibrils) grouped into fascicles. The structural layers include the endomysium (covering fibers), perimysium (covering fascicles), and epimysium (covering the whole muscle). Muscles attach to bones via tendons; the origin is the immovable end closest to the body, and the insertion is the movable end. There are three types of muscle fibers: skeletal muscle (forming skeletal muscles), cardiac (myocardial) muscle (allowing the heart to beat independently), and smooth muscle (forming organs and vessels).

Muscle disorders include fasciitis (fascia inflammation), fibromyalgia (chronic condition with fatigue and muscle/joint pain), and myasthenia gravis (autoimmune disease affecting the neuromuscular junction, causing drooping eyelids and difficulty swallowing). Muscle tone conditions include atonic (lack of tone), dystonia (abnormal tone), and hypotonia. Repetitive motions can lead to carpal tunnel syndrome (compression of nerves in the wrist) or compartment syndrome (compression of nerves and vessels within fascia). Paralysis results from nerve damage and includes myoparesis (slight paralysis), hemiplegia (total paralysis on one side), and quadriplegia (paralysis of all four extremities).

The Skeletal System

The human skeleton consists of 206206 bones connected by ligaments at articulations or joints. The system is divided into the axial skeletal system (8080 bones including the skull, spinal column, hyoid, middle ear ossicles, and rib cage) and the appendicular skeletal system (126126 bones of the appendages). Bones are categorized into four types: long, flat, short, and irregular. All bones have blood and nerve supplies and are covered by periosteum. Long bones have an internal medullary cavity hosting bone marrow.

The spinal column protective divisions are: cervical (C1-C7 in the neck), thoracic (T1-T12 in the thorax), lumbar (L1-L5 in the lower back), the sacrum (five fused vertebrae), and the coccyx or tailbone (33 to 55 fused vertebrae). Joints are classified as fibrous (inflexible, like skull sutres), cartilaginous (slight movement, like the pubic symphysis), or synovial (wide range of motion, like ball-and-socket or hinge joints). Synovial joints contain a capsule and lubricating fluid.

Skeletal pathologies include ankylosis (loss of joint mobility), arteriosclerosis (defined in context as stiffness of the joy common in the elderly), arthritis (over 100100 types including rheumatoid and osteoarthritis), and gout (uric acid crystal deposits). Bone density issues include osteoporosis and osteopenia. Fractures are classified as closed (no skin puncture), open (breaks skin), comminuted (crushed), greenstick (partial break), or pathologic (weakened by disease). Bone marrow transplants (BMT), either allogenic (from a donor) or autologous (patient's own cells), are used to treat leukemia and lymphoma.

The Endocrine System

The endocrine system uses chemical messengers called hormones secreted by glands to maintain homeostasis. The pineal gland is in the brain and secretes melatonin for the circadian cycle. The hypothalamus controls the pituitary gland, which is divided into anterior and posterior lobes. The anterior lobe secretes ACTH (adrenal cortex growth), FSH (estrogen/sperm production), GH (body growth), LTH/prolactin (breastmilk), LH (ovulation/testosterone), MSH (melanin), and TSH (thyroid growth). The posterior lobe stores ADH (blood pressure/water control) and oxytocin (uterine contractions).

Other glands include the thyroid (regulates metabolism via thyroxine and triiodothyronine) and parathyroid (regulates calcium). The thymus secretes thymosin for the immune system before birth. The pancreas acts as both an endocrine and digestive organ, secreting glucagon (increases glucose) and insulin (moves glucose into cells). Adrenal glands include a cortex (secreting androgens, aldosterone, and cortisol) and a medulla (secreting epinephrine for stress). Gonads include ovaries (producing eggs and progesterone/estrogen) and testicles (producing sperm and testosterone).

Endocrine disorders include acromegaly (growth hormone excess after puberty), Hashimotos disease (autoimmune thyroid destruction), Graves' disease (immune attack causing excess thyroid hormone), and Addison's disease (insufficient cortisol or aldosterone). Diabetes Mellitus includes Type 1 (autoimmune islet cell destruction) and Type 2 (insulin resistance often related to obesity).

The Cardiovascular System

The vascular system consists of arteries (carrying blood away from the heart, like the aorta), veins (carrying blood to the heart, like the vena cava), arterioles, venules, and capillaries. The heart is a hollow muscle with three wall layers (epicardium, myocardium, endocardium), four chambers (atria and ventricles), and four valves. Its electrical system includes the SA node, AV node, bundle of His, and purkinje fibers to maintain rhythm.

Blood is a fluid tissue composed of 55%55\% plasma (which is 91%91\% water and proteins like fibrinogen) and 45%45\% formed elements. Formed elements include erythrocytes (red blood cells transporting oxygen via hemoglobin), leukocytes (white blood cells like neutrophils, basophils, eosinophils, lymphocytes, and monocytes), and thrombocytes (platelets for clotting). Circulation types include pulmonary (between heart and lungs) and systemic (throughout the whole body except for coronary circulation).

Cardiovascular conditions include coronary artery disease (CAD), myocardial infarction (heart attack caused by arterial occlusion), and arrhythmias like asystole (flat line) or bradycardia (slow heart rate). Congestive heart failure (CHF) can be left-sided (causing pulmonary edema) or right-sided (causing body-wide edema). Blood pressure is measured as systolic (ventricular contraction) over diastolic (ventricular relaxation); normal is less than 120/80 mmHg120/80\,\text{mmHg}, while hypertension is significantly high blood pressure. Hematological disorders include sepsis (blood poisoning) and anemia (low red blood cell count).

The Respiratory System

The respiratory system performs gas exchange, trading oxygen for carbon dioxide. The pathway includes the nostrils, nasal cavities, pharynx, larynx, trachea, primary bronchcus, bronchioles, and alveoli (the site of transfer). The right lung has three lobes and the left has two. Breathing involves the diaphragm; inhalation creates a vacuum pulling air in, while exhalation forces air out. Normal breathing is eupnea, while bradypnea is a rate of 1010 breaths per minute or less and tachypnea is 2020 per minute or faster.

Respiratory disorders include Chronic Obstructive Pulmonary Disease (COPD), which includes chronic bronchitis and emphysema. Asthma is an inflammatory spasms of the bronchioles. Upper respiratory infections, allergic rhinitis, and croup (barking cough in children) are common. Severe issues include anoxia (total oxygen absence) and hypoxia (low oxygen). Sudden Infant Death Syndrome (SIDS) is the unexplainable death of a healthy sleeping infant, often between 22 and 66 months old.

The Lymphatic and Immune Systems

The lymphatic system includes lymph (interstital fluid), lymph vessels with valves, and approximately 700700 lymph nodes clustered in the neck, groin, and chest. Three major node groups are cervical, axillary, and inguinal. Lymph contains lymphocytes: Natural Killer (NK) cells, B cells (produce antibodies), and T cells (cell-mediated immunity). Other structures include the tonsils (adenoids, palatine, and lingual), thymus gland, vermiform appendix, and the spleen (filters blood in the LUQ).

The immune system protects through barriers (skin), acids (digestive), and specialized reactions. Antigens are foreign substances that trigger antibody production by immunoglobulins (IgG,IgA,IgM,IgD,IgEIgG, IgA, IgM, IgD, IgE). Phagocytes like monocytes, macrophages, and dendritic cells destroy pathogens. Autoimmune disorders, such as Crohn's disease or myasthenia gravis, occur when the system attacks healthy tissue. HIV is a blood-borne infection damaging T cells, leading to AIDS.

The Gastrointestinal System

The GI system includes the upper tract (oral cavity, pharynx, esophagus, stomach), lower tract (small intestine: duodenum, jejunum, ileum; large intestine: cecum, colon, rectum, anus), and accessory organs (liver, gallbladder, pancreas). Digestion breaks food into nutrients; metabolism includes anabolism (building cells) and catabolism (releasing energy); absorption move nutrients to blood. Mastication is chewing, and deglutition is swallowing.

Pathologies include aphthous ulcers (canker sores), periodontal disease (gingivitis), and GERD (upward acid flow). Stomach conditions include gastritis and peptic ulcers. Intestinal disorders include celiac disease (gluten reaction), irritable bowel syndrome (IBS), and inflammatory bowel disease (IBD), such as ulcerative colitis. Liver issues include jaundice (yellowing from bilirubin) and cirrhosis. Nutritional disorders include anorexia and bulimia.

The Urinary System

The urinary system consists of two kidneys, two ureters, the urinary bladder, and the urethra. The kidneys filter 200 quarts200\,\text{quarts} of blood daily to produce about 2 quarts2\,\text{quarts} of urine, which is 95%95\% water. Filtration occurs in the nephron, which includes the glomerulus and bow mans capsule. The processes are filtration, reabsorption, secretion, and excretion.

Common disorders include renal failure (kidney failure), uremia (toxic waste buildup), and nephrotic syndrome (protein loss in urine). Kidney stones (calculi) can be nephroliths (kidney), ureteroliths (ureter), or cystoliths (bladder). Benign prostate hyperplasia (BPH) causes difficult urination in men over 5050. Terms like anuria (absence of urine), nocturia (excessive nighttime urination), and polyuria (excessive urination associated with diabetes) describe voiding pathologies.

The Reproductive Systems

The male system includes the scrotum, testicles (producing sperm), epididymis (storage), vas deferens, seminal vesicles, prostate gland, and bulbourethral glands (cowpers glands). Female anatomy includes the vulva (clitoris, bartholins glands), ovaries (producing ova/eggs), fallopian tubes with fimbriae, uterus (perimeteuim, myometrium, endometrium), and vagina.

Reproductive physiology involves the menstrual cycle, ovulation on roughly the 1414th day, and conception (forming a zygote). Pregnancy trimesters are about 13 weeks13\,\text{weeks} each, with gestation lasting 280 days280\,\text{days} (40 weeks40\,\text{weeks}). Labor stages include dilation/effacement (11st), delivery of the child (22nd), and expulsion of the placenta afterbirth (33rd). Disorders range from erectile dysfunction and cryptorchidism in males to endometriosis and pelvic inflammatory disease (PID) in females. STDs include chlamydia, gonorrhea, syphilis, and HIV.

The Nervous System

The nervous system is divided into the Central Nervous System (CNS, brain and spinal cord) and the Peripheral Nervous System (PNS). CNS protection includes three meninges layers: dura matter (outer), arachnoid membrane (middle), and pia mater (inner), with subarachnoid space for cerebral spinal fluid (CFS). The cerebrum is the largest brain part, with the frontal (motor/behavior), parietal (sensory), occipital (eyesight), and temporal (hearing/smell) lobes.

Neurons communicate via neurotransmitters like Acetylcholine (muscles), Dopamine, Epinephrine (adrenal), and Serotonin. Nerve bundles are protected by endoneurium, perineurium, and epineurium. Disorders include migraines, dementia (Alzheimer's), Parkinson's disease, and strokes (CVA). Stroke symptoms include facial droop, arm drift, and speech abnormalities. Seizures include tonic-clonic (grand mal) and absence (petit mal) types.

The Special Senses

The eye is shielded by adnexa (orbit, eye muscles, eyelashes, conjunctiva, and lacrimal apparatus). The eyeball has three layers: sclera (outer white), choroid (middle vascular), and retina (inner layer with rods for black-and-white and cones for color). Disorders include cataracts (loss of lens transparency), glaucoma (increased intraocular pressure), and refractive errors like myopia (nearsightedness) and hyperopia (farsightedness).

The ear receives sound through the pinna and auditory canal, vibrating the tympanic membrane (eardrum) and ossicles (malleus, incus, stapes). The cochlea converts vibrations to nerve impulses. Equilibrium is maintained in the semicircular canals. Hearing loss can be conductive (blockage) or sensoruneural (nerve damage). Taste, or gustation, involves five main tastes: sweet, sour, bitter, salty, and umami.