Protozoa are single-celled, microscopic eukaryotic organisms that can move independently. They are classified into four main phyla: Protozoa, Ciliophora, Sarcomastigophora, and Apicomplexa. Many protozoa are heterotrophic and either free-living or parasitic. They reproduce asexually through binary fission or sexually through conjugation. Some important human diseases caused by protozoan parasites include malaria, amebic dysentery, giardiasis, African sleeping sickness, Chagas disease, and toxoplasmosis.
6. Classification
• Domain- Eukarya
• Kingdom- Protista
– Along with algae, slime molds, and water
molds
• Four phyla are usually used
– Protozoa
– Ciliophora
– Sarcomastigophora
– Apicomplexa
7. Adaptations
• Eyespot- localized region of
pigment that can detect
changes in the quantity and
quality of light
• Cyst- dormant form of a
protozoan that has a
hardened outer covering to
help them survive harsh
conditions
9. Phylum Protozoa
• Hundreds of species of ameba
• Live in sand; mud; rocks; and shallow,
slow moving streams and ponds
10. Phylum Protozoa
• Pseudo- false
• Podia- foot
• Pseudopodia- cytoplasmic extensions
pushed out from the amoeba
18. Phylum Ciliophora
• 8000 species
• Paramecium-
large group of
ciliates
• Feed on bacteria
and algae
• Covered with
cilia
20. Phylum Ciliophora
• Pellicle- clear elastic layer of protein that
surrounds the cell membrane
• Oral Groove- funnel-like depression lined
with cilia that sweeps food down into the
mouth pore
21. Phylum Ciliophora
• Gullet- forms food vacuoles
• Anal pore- where waste is expelled
• Macronucleus- multiple copies of DNA and
sexual reproduction
28. Phylum Apicomplexa
• 6,000 species
• Adult forms have no means of
locomotion
• Most are parasitic
• Toxoplasmosis- a disease
that usually causes no
problem in an adult but can
harm a developing fetus-
common in domestic cats
29. Phylum Apicomplexa
• Plasmodium- malaria
– Severe chills, fever, headache, sweating,
fatigue, and great thirst
– Vector- female anopheles mosquito