prokaryotes and protists

Explain the exo-erythrocytic cycle of plasmodium spp

1. Infected female Anopheles bites a human injecting plasmodium spp sporozoites inside the bloodstream from the saliva of the mosquito. The sporozoites travel to the liver

2. The sporozoites invade the parenchyma hepatocytes and form the first schizont

3. The first schizont produces meorozites through schizogony

4. The merozoites break out of the hepatocytes and enter the bloodstream.

Explain the erythrocytic cycle

1. The signet ring stage forms a mature trophozoite and later the schizont form through schizogony

2. The schizont acquires cytoplasm undergoes karyokinesis and cytokinesis and divides into merozoites

3. The red blood cells burst open to release the merozoites and waste products into the bloodstream

4. Each merozoite invades another red blood cell to form a trophozoite and the asexual cycle is repeated

5. The trophozoite can also produce gametocytes which the mosquito can ingest when feeding on a human

Explain the sporogonic cycle of plasmodium spp

1. When a mosquito bites an infected human it ingests gametocytes

2. Gametocytes develop into mature sex cells called microgametocye(male) and macrogametocye(female) , fertilised gametes develop into moving ookinetes(2n)

3. Ookinetes burrow through the mosquito midgut wall and form oocyst on the exterior surface

4. Inside the oocyst thousands of active sporozoites develop through sporogony

5. The oocyst eventually bursts releasing sporozoites into the body cavity

6. Sporozoites travel to the mosquitos salivary glands

The two stages of paramecium lifecycle

Conjucation and binary fission

Explain the lifecyle of paramecium spp

1. Two cells of compatible mating types align side by side and partially fuse

2. Meiosis of micronuclei produces 4 haploid micronuclei in each cell

3. 3 micronuclei in each cell disintegrate

4. The remaining micronucleus in each cell divides by mitosis

5. The cells swap one micronuclei

6. The mating cells seperate

7. The two micronuclei fuse

8. Three rounds of mitosis produces 8 micronuclei

9. 4 micronuclei become macronuclei

10. Two rounds of binary fission yield 4 daughter cells

Endosymbiosis

A symbiotic relationship where one organism lives inside the other

Endosymbiont Theory

States that some of the organelles in todays eukaryotic cells were once prokaryotic microbes

Primary endosymbiosis

Process in which a prokaryotic(host)unicellular organism engulfs another prokaryotic organism which lives within the host cell and ultimately becomes an organelle in the host cell

first Endosymbiosis in Eukaryotic Evolution

A prokaryotic amoeboid organism

ingested an aerobic bacterium

(i.e., today’s mitochondria),

which conferred eukaryotic

characteristics to the prokaryotic

organism

Second Endosymbiosis in Eukaryotic Evolution

Chloroplasts/plastids may be

derived from a photosynthetic

cyanobacterium that was

engulfed by heterotrophic

eukaryotic cells (endosymbiosis)

Evidence of Endosymbiosis in Eukaryotic Evo

MAD DR

What does MAD DR stand for in endosymbiosis in eukaryotic evolution

The evidence of endosymbiosis in eukaryotic evolution being membranes, antibiotics, division,DNA and ribosome

Secondary endosymbiosis

process where eukaryotic organisms

feed on one another

• Some of the

eukaryotic organisms

became part of the

original eukaryotic

organisms’ bodies,

resulting in more

complex organelles