寄生虫阿米巴.ppt

寄生虫阿米巴
第一页，共132页
General Properties of the Protozoa
第二页，共132页
Eukaryotic, unicellular animals with full vital functions.
Smallest parasites, 2-200µm, and best seen with a high power objective lens of a good microscope.
Grow and reproduce very fast.
General Introduction
to Protozoa
第三页，共132页
4. Wide distribution in nature.
Total species: about 200,000;
Free-living: majority;
Parasitic: around 10,000;
Medical protozoa: minority about 40.
General Introduction
5. Medical Protozoa: resident in human
fluid, tissue or cells, which may be
harmful to their hosts.
第四页，共132页
3. Nucleus for reproduction; morphologically
may be vesicular form or compact form.
Basic Structures:
2. Cytoplasm: Ectoplasm for locomotion &
ingestion; Endoplasm for metabolism.
1. Plasma membrane: related to
independence, invasion, physiological
balance.
4. Locomotive organelle:
pseudopodium, flagellum, cilium.
第五页，共132页
Locomotion: locomotive organelles:
Pseudopodium: a temporary ectoplasmic extrusion, by means of which an amoeba moves about or engulfs food (Amoeba) Pseudopodium
Flagellum: a long, mobile, whip like projection
from the free surface of a cell (Trichomonas vaginalis)
Cilia: a minute vibratile（可振动的）, hairlike process
projecting from the free surface of a cell (Ciliates)
Physiological functions
Flagellum
Cilia
第六页，共132页
Physiological functions
Feeding and digestion:
Pinocytosis----engulfing soluble matter in digestive
vacuoles
Phagocytosis----engulfing particulate matter in
digestive vacuoles
In some species, food is ingested at a definite site
(cytostome, . Plasmodium spp.)
第七页，共132页
Mode of reproduction
Binary fission – results in 2 daughter cells (almost all )
Schizogony – multiple fissions resulting in multiple cells (malaria parasites)
Budding:
External buddi