21.3_The_Ecology_of_Protists

1 Review Give three examples of photosynthetic
protists
Predict How would ocean food chains change in the
absence of photosynthetic protists
2 Explain By what two methods do parasitic protists
primarily spread disease
Form an Opinion Why are protist caused disease
more widespread in tropical areas of the world.
CH 21 PROTISTS AND FUNGI
21.3 The Ecology of Protists
Autotrophic Protists




Phytoplankton
Red and brown algae
Euglena
Dinoflagellates.



Base of many aquatic food chains
Half of Earth’s photosynthesis is carried out by
phytoplankton
Phytoplankton feeds both shrimp and some
whales.



Provide coral reefs with energy and also calcium
carbonate
Brown kelp can grow up to 60 meters
Can create “algae blooms”
 Red
tide.
Heterotrophic Protists
Amoebas


Surround a cell or particle and take it inside
themselves to form a food vacuole
Food vacuole
 Small
cavity in the cytoplasm that temporarily stores
food
 Materials are digested and nutrients removed
 Wastes stay in and food vacuole brings to edge of cell.
Ciliates


Use cilia to sweep food particles into gullet
Gullet
 Indentation

in one side of the organism
Particles are forced into food vacuoles that form at
base.


Food vacuoles pinch off into cytoplasm and fuse
with lysosomes
Waste materials are emptied when the food
vacuole fuses with the anal pore.
Slime Molds


Key roles in recycling nutrients in an ecosystem
Uses decaying organic material.
Slime Molds

Amoeba like cells.

Forms together into a large structure known as a
plasmodium.


Plasmodium develops sporangia
Meiosis produces haploid spores to continue the
cycle inside.
Mutualistic Protists

Trichonympha and termites.
Parasites and Disease

Debilitating intestinal diseases, African sleeping
sickness, and malaria.
Intestinal Diseases

Giardia
 Diarrhea


Amebic dysentery
Cryptosporidium
 Chlorine

causing found in streams
resistant, found in city water
African Sleeping Sickness
 Trypanosoma
carried by Tsetse fly.
Malaria

Plasmodium carried by Anopheles mosquito.