Protozoa 27.11.23 Flashcards
Define protozoa
Single-called eukaryotic organisms
What is the main biological role of protozoa?
Consumers of bacteria, algae, microfungi
How do all protozoa engulf food?
By phagocytosis and then digest it in intracellular
How are protozao part of an outdate classification
protozoa include both plants and animals and in reality is a group including a variety of clades within eukaryotes
What are the 5 major groups of protozoa?
Flagellates
Amoebae
Sporozoans
Ciliates
Microsporidia
Describe flagellates
Flagellum as main locomotory organelle
Usually reproduce by binary fission
Intestinal flagellates or other body sites
Describe amoeba
Move by means of flowing cytoplasm and production of pseudopodia
Describe sporozoans - malaria
No locomotory extensions
All species parasitic
Most intracellular parasites
Reproduce by multiple fission
Describe ciliates
Cilia that beat rhythmically at some stage in lifecycle
2 types of nuclei – macro/micronucleus
Describe microsporidia
Production of resistant spores
Unique polar filament; coiled inside spore
Little known about human disease
What protozoan infection causes malaria?
Plasmodia sporozoan
What 5 species cause human disease of malaria?
P.falciparum/orale/vivax/malariae/knowlesi
How is malaria transmitted?
Transmitted by bite of female Anopheles mosquitoes:
Infection acquired during feeding from infected human
Infected for life
Life span 3-4 weeks
Describe malaria life cycle
Liver stage in P.ovale and P.vivax has additional hypnozoite stage
Lie dormant and cause late relapse by reactivating months later
Not eradicated by most conventional anti-malarial treatments
Symptomatic malaria: fever, haemolysis
Clinical features of malaria
Very varied
Fever almost invariable
Other common;
Chills and sweats
Headache
Myalgia
Fatigue
Nausea and vomiting
Diarrhoea
These acute symptoms common to all 4 species
