describe the life cycle of the Plasmodium parasite
Anopheles mosquito bites human and passes sporozoites of the malaria parasite - the sporozoites travel via blood to the liver where they infect liver cells & release morozoites into blood and they infect RBCs - infected RBCs lyse, more are infected and merozoites develop into gemetocytes that are ingested when another mosquito comes along - inside mosquitos gut gametocytes become gametes which are fertilized and zygote forms - meiosis - oocyst - oocyst releases sporozoites and cycle repeats
why is studying mosquito evolution important?
studying mosquito evolution is important because it helps us understand and deal with the emergence of insecticide resistance
Sickle Cell Anemia
HbS heterozygotes are less prone to infection which causes balanced polymorphism b/c it causes incs in homozygotes for HbS do to its heterozygote advantage
what causes sickle cell anemia
codon change w/in beta-globin gene from GAG to GTG (glutamine to valine) which causes the RBCs to "sickle"
how can sickle cell anemia cause arterial damage
the sickled cells bind to and activate vessel lining which attracts other cells that build up in vessel, this can lead to an obstruction which causes O2 starvation (i.e. stroke)
blood disorder; like sickle cell creates balanced polymorphism because people with this disease have some resistance to malaria
what steps were taken to eradicate malaria in the United States?
draining and oiling breeding areas, treating lg. pops w/quinines, screen installation, building dams to isolate mosquitos, improving cycle of poverty, and DDT
insecticide, freed 1/3 of victims worlwide from malaria by 1970; was eventually banned do to environmental concerns
diff drugs and drug combos for diff plasmodium species and diff stages of the disease; most drugs contain some type of quinine derivative however many strains have become resistant; also the symptoms can be treated via liquids, sponge bath with cool h2o, etc
current vaccine targets include 3 basic stages: sporo/merzoitc and gametocyte; there are also current clinical trials on prophylatic treatment (treating before it strikes)
current studies on treating the mosquitos with fungus so they cannot infect humans with plasmodium
how can plasmodium make humans more attractive to mosquitos?
by triggering changes in breath and body odors
global warming and malaria
global warming may inc prevalence of malaria and cause outbreaks in previously eradicated areas