PART 9

21 1 0

by ADITIbts311

by ADITIbts311

KINGDOM PROTISTA

These are unicellular eukaryotes. Some of these are colonial. These are rarely multicellular. Most of these are aquatic. They can be photosynthetic(seaweed, grass), heterotrophic(animals) or myxotrophic(it is an organism that can use a mix of different sources of energy and carbon, instead of having a single trophic mode on the continuum from complete autotrophy at one end to heterotrophy at the other.)[Venus flytrap, Euglena]

ENDOSYMBIOTIC THEORY

This theory says that, photosynthetic prokaryot was engulfed by other heterotrophic prokaryot and established symbiotic relation. Photosynthetic organism got protection, and heterotrophic organism got nutrition. This photosynthetic organism then became chloroplast. Similarly, other bacterial cells were also engulfed and formed different different organelles. Mitochondria was formed first, then chloroplast and then other organelles got formed. THEREFORE, MITOCHONDRIA IS FOUND IN ALL ORGANISMS EXCEPT PROKARYOTES

PROTISTA ARE FURTHER DIVIDED INTO FIVE SUBGROUPS

1] Chrysophytes: These are phototrophic. These are further divided into 2 subgroups

A] DIATOMS: These are chief producers of ocean. Microscopic. Photosynthetic. Phytoplankton-which means plant like which moves with water. Mostly marine, rarely freshwater. They have overlaping and strong cell wall made up of silica. When these diatoms die, they form gritty structure and later can be used for filtration of syrup and oils.

B] DESMIDS: These are golden algae. They have golden and brown carotenoids. These are photosynthetic too. These are found in both fresh and marine water.

2] DINOFLAGELLATES(daayan): These are phototrophic. These are mostly marine. Rarely freshwater. Photosynthetic. Very colorful due to different pigments. Covered by celluloisic plates. These have two flagella. One is longitudinal and the other is transverse which makes swirling possible. e.g Gonyaulax--> which are resposible for red tide.

Dinoflagellate releases harmful toxin which gets accumulated with molluscs. These molluscs are eaten by humans and causes shellfish poisoning which might lead to death.

3] EUGLENOID: These are myxotrophic. Photosynthetic if sunlight is present and becomes predator is sunlight isn't present. They do have chlorophyll. They have two unequal flagella one small and the other one big. It has a cover made up protein which is called as pellicle. These are mostly fresh water.

4] SLIME MOULDS: These are heterotrophic. These are basically of two types:-

A] CELLULAR: THIS IS NOT INCLUDED FOR NOW....

B]PLASMODIAL:- These are heterotrophic. and multinucleated. It will grow from taking nutrition from barks and leaves. It grows in damp places. The grown structure which is multinucleated cell mass and giant super cell is called as plasmodium. Reproduction is by frooping bodies.

5] PROTOZOANS:- No cell wall, but have some covering. These are heterotrophic. These are considered as ancestors of animal cell.

1] AMOEBOID PROTOZOANS:- They move through pseudopodia (false legs). Some of them have silica covering. Amoeba is aquatic, but antamoeba is parasitic and causes amoebic desentry. e.g. amoeba, antamoeba

2] FLAGELLATED PROTOZOANS:- These are totally heterotrophic. e.g Trypanosoma(which causes sleeping sickness and is a vector which is caused by Tse Tse fly), Trichomonas

3] CILIATED PROTOZOAN:- They have cilia. Aquatic and have 2 nucleus(micro, macro). Also called as slipper animal cule.

4] SPOROZOAN:- Parasitic. Expect other organism at spore light state. e.g Plasmodiumwhich causes malaria.