It is of all single celled eukaryotes
Forms a link between plants, animals and fungi.
⛔(i) Chrysophytes -Has diatoms and golden algae/desmids
Fresh water/marine, photosynthetic, microscopic plankton.
▪️Chief producers of sea
▪️ Cell walls have silica which makes it indestructible and cell walls
overlap to it together like a soap box.
▪️ Their accumulation forms ‘Diatomaceous Earth” (gritty soil)
▪️It is used in polishing, iltration of oils and syrups.
⛔Dinolagellates
▪️Marine, photosynthetic, cell wall has stiff cellulose plates.
▪️Two flagella–one longitudinal and other transverse in a furrow between wall plates.
▪️Example : Gonyaulax multiples rapdily, make sea appear red (red tides) and produce toxins to kill marine animals.
⛔(iii) Euglenoids
▪️Found in stagnant fresh water.
Have protein rich layer ‘pellicle’ which makes body lexible.
▪️Photosynthetic in presence of sunlight but become heterotrophs if they do not get sunlight. (Mixotrophic nutrition)
▪️Example : Euglena
(iv) Slime Moulds :
▪️Saprophytic protists
▪️Under suitable conditions form an aggregates called plasmodium,
grows on decaying twigs and leaves.
▪️ During unfavourable conditions, plasmodium differentiates and
forms fruiting bodies bearing spores at their tips.
▪️Spores have true walls which are extremely resistant and survive for
many years and dispersed by air currents.
⛔(v) Protozoans : Are heterotrops and live as parasites. Have four major
groups.
▪️Amoeboid : Catch prey using pseudopodia, e.g., Amoeba. Entamoeba
are parasite.
▪️Flagellated : Have one or more lagella. Cause disease like Sleeping
Sickness e.g., trypanosoma.
▪️Ciliated : Have clilia to move food into gullet and help in locomotion.
e.g., Paramoecium.
Sporozoans : Have infective spore like stage in life cycle, e.g.,
Plasmodium which causes malaria.
