plamodium Flashcards
(74 cards)
phylum and order of plasmodium
phylum: Apicomplexa
- unique feature: apical complex (to help invade host cells)
order: Haemosporida
- live within the blood, specifically blood cells
- intracellular parasites
apical complex purpose
- for host penetration
● Intermediate host: man
- whr parasite develops
● Final host: mosquito
-whr parasite completes its life cycle - for cell invasion
[esp RBC in bloodstreams]
what are the distinguishing features between these
1. Amoeba
2. Flagellates
3. Ciliates
4. Apicomplexa
- Amoeba – pseudopodia
- Flagellates – flagella
- Ciliates – cilia
- Apicomplexa – apical complex
plasmodium spp is aka
malarial parasite
it refers to multinucleated mass
plasmodium
- seen during diff lifecycle of malarial parasites
[because during its life cycle, it has multiple nuclei in some stages.]
- exhibit multinucleation (smthing to do w nucleus, w cell division)
[divides in a way that involves many nuclei forming before the cells split]
two life cycles (alternating) of the plasmodium spp
- asexual cycle
● “Schizogony”
● Occurs within the RBCs of vertebrate hosts (humans – intermediate hosts)
- consists of schizogony and gametony
[parasite multiplies and bursts the RBCs, causing malaria symptoms.]
- sexual cycle
● “Sporogony”
● Occurs within the mosquitoes (female anopheles) - (final hosts)
- consists of sporogony (8-35 days)
[parasite develops and spreads when mosquitoes bite humans.]
what are the plasmodium spp that can clinically infect the humans
[MVF.OK]
- Plasmodium malariae
● Discovered by Alphons Laveran in 1881 - Plasmodium vivax
● Discovered by Giovanni Battista Grassi and Raimondo Feletti in 1890 - Plasmodium falciparum
● First discovered by Laveran in 1881
● Renamed by William Welch in 1922 - Plasmodium ovale
● First described by Stephens in 1922 - Plasmodium knowlesi
● Named by John Sinton and Mulligan in 1932
what are the stages of development and its morphology
morphology: refer to index card
- trophozoite
- early trophozoite
- developing trophozoite - schizont
- immature schizont
- mature schizont - gametocyte
- microgametocytes (male sexual form)
- macrogametocytes (female sexual form)
morphology of trophozoite in general
○ Single nucleus
○ Ring-shaped or ring forms
○ With a red chromatin dot
○ Small amount of blue cytoplasm (Giemsa or Wright’s stain)
earliest stage after the invasion of RBCs
trophozoite
- aka trophic stage
stage after invading healthy RBC
early trophozoite
- ring stage or ring forms
how does the hemozoin form
plasmodium spp digests Hb from RBC for foos
since it cant use the iron part of Hb, it turns into hemozoin (a waste product)
it is an asexual stage where it occurs within the RBCs of the vertebrate hosts
schizont
- parasite usually divide when growing
- multiple rounds of nuclear division (mitotic division)
Occurs after the trophozoite stage and before mature schizont stage
immature schizont
this is where active chromatin replication is evident
immature schizont
- crowing chromatin w visible cytoplasmic materials
presence of fully-developed merozoites and absence of cytoplasmic material
mature schizont
- can produce a specific number of merozoites depending on the species
it is the sexual stage of the plasmodium life cycle and has a compact cytoplasm and one large compact and round or elongated nucleus.
gametocyte stage
- happens in the RBC
- prep for transmission to mosquitoes for reproduction
why is there an absence of nuclear division in the gametocyte
absence in human host in the stage of gametocytes as
- malarial parasites consumes too much energy
- since malarial parasites want to focus on survival and transmission rather than rapid division or raid proliferation
gametocyte may be differentiated as
Microgametocytes (male sexual form)
Macrogametocytes (female sexual form)
where can the Plasmodium falciparum be found
most frequently observed in peripheral blood (the blood flowing in your veins and arteries) due to its ability to circulate freely
= ez to detect under microscope
what is the shape of the gametocytes in Plasmodium falciparum
Banana/sickle/sausage/crescent
- common to both macrogametocyte and microgametocyte
*it is the key feature
what is the shape of the cytoplasm in Plasmodium falciparum mature trophozoite
comma-shaped
*heavy ring forms not commonly seen
what does macrogametocyte and microgametocyte have in common in the gametocyte stage of P. falciparum
○ Reddish pink nucleus
○ Few blue-black granules [hemozoin pigments] in the center of the cytoplasm or scattered.
Why are they there?
The parasite does not completely get rid of the digested hemoglobin, so hemozoin granules remain inside its cytoplasm.
Small red-staining structures found in RBCs infected by Plasmodium falciparum; seen only after staining.
Maurer’s dots
- aka Maurer’s clefts
- structures observed in an infected RBCs
- not in gametocytes rater seen inn RBCs