Disease: an abnormal condition of an organism that impairs bodily functions, may be caused by external factors like infectious diseases, internal dysfunctions such as autoimmune diseaseWhat is an emerging disease? Something new to the population that has never before been detectedEpidemic: spread or growth in a populationPandemic: continental or world-wide scale of diseaseEpidemiology: study of factors affecting the health/illness of populations, often focused on spread of diseasesEarly thoughts on the causes of disease – - Human luxury, living in excess- Black Death introduced the idea of quarantine and contagions- Imbalance of ‘four humors’- Spontaneously generated (NOT TRUEE)Rob Starks bastard: Dr. John Snow- Father of epidiomology- Used a map to track spread of disease- Before, it was thought that air/odors caused disease, but Snow was able to map the spreadand correlate it with certain water pump locations - Contributed towards adoption of anesthesia and hygieneDr. Ignez Phillipp Semmmelweis- Physician and early pioneer of antiseptic- Helped w/ child birth and noticed high rate of child fever- Mapped clinics – 1. w/ medical students, 2. w/ midwivesHe realized medical students were performing autopsies and then aiding childbirth right after, could be causing child fever. He instituted a policy of hygiene and child death rates decreased. He was not very accepted though and ironically went insane due to hygiene problems.Dr. Joseph Lister- Used carbolic acid to was wounds, surgical instruments, hands- No wooden handles as they retain shit- Father of modern antisepticsWhere do disease parasites originate? Other parts of world, animals, mutationsHow do epidemics spread? Airborn, pathogens, population sizesIncrease in population density  incrase in encounters between individuals  increase in spreadof diseaseLogistic Population GrowthN+ is the population size at one timeWhat will contribute to change in population size? T(time) + 1N sub, (t+1) = N sub t + birth – death + immigrants – emigrantsPer capita death: d/NDeath over individual over timeSame for birth: b/NBirth over individual over timePer capita growth rate:R= birth – death/NPositive R = growing populationNegative R = shrinking populationG is the growth increment, # of individuals added or lost during timeG= birth – deathG= bN – dNG= (b-d)N but r = b-d so G = rNN sub(t+1) = N sub (t) + G (size of the new population is the old population + G)Population growth may be exponential or logisticExponential:- When resources are unlimited- J shaped curve- R stays constantLogistic:- S shaped curve- Growth will slow and halt as population reaches carrying capacityBiotic Potential: Max. reproductive rateEnvironmental Resistance: any factor that reduces population growthCarrying Capacity: Max # of individuals of any species that can be supported in an areaDensity dependent population control- Growth slows because density increaseso Causes: running out of resources, predation, increased exposure to diseaseo Biotic population control conditionsDensity independent population control- Unrelated to population sizeo Causes: catastrophic eventso Abiotic population control conditionsDisease Transmission and ImmuintyImmune Systems:- Innate immunityo First line of defenseo Always present and ready to functiono Physical barriers (sickness)- Adaptive immunityo Recognize and remember encountersAdaptive/Acquiredo Macrophages are innate defenses:o Engulf and dismantle pathogens, links pathogens and antigens to a self protein on the surfaceo Macrophages w/ antigens on surface travel to lymph nodeeso Lymph node has helper T cells initiate immune responses by binding to mircophage and initiates adaptive immune response stagesAntigens: foreign carbohydrates or proteins that are the target of adaptive and immune responsesB and T cells respond to only 1 antigenMicrophages: trigger immune responses by activating helper T cellso Adaptive immune response stages:o Cell mediated immunity – defensive cells attack and kill invaders by direct cell to cell contacto Humoral immunity – relies on plasma B cells secreting antibodies (specific defensive proteins)Variation in immunity effected by:o Sleepo Nutritiono Disease historyo Stresso Chemotherapyo Immunity reduced in infancy due to lack of exposure to new antigens, as well as old age due to slow cellular division ratesResistanceWhy do we renew flu shots?o Large population size of viruso Short generation timeo High mutation rateso Viral antigens change often and antibodies stop fitting/become less effectiveAntibiotics are agents of natural selectionOrigins of Mitochondria and Chloroplast- May have originally been free living bacteria captured by endocytosiso Size of mitochondria and chloroplasts is similar to bacteriao Both have double membraneso Circular DNA and ribosomes- Vaccines = antigens- Exocytosis = cellular secretion- Activated Bcells have rough ER because they synthesize large amounts of protein for making antibodies- Memory cells help immunity against