This document summarizes key characteristics of several groups of protists. It describes that protists can be unicellular or colonial, with some having multinucleate stages. They possess defining organelles like nuclei and mitochondria. Nutrition includes photosynthesis, absorption, and ingestion. Reproduction can be both asexual and sexual. Specific groups discussed include diatoms, dinoflagellates, euglenoids, slime molds, flagellates, amoebas, ciliates, and apicomplexans. Their characteristics, habitats, modes of nutrition, locomotion structures, and life cycles are outlined.

1. CHAPTER-2

3.  GENERAL CHARACTERISTICS :
 They include solitary unicellular or colonial unicellular
eukaryotic organisms which do not form tissues.
 Simple multinucleate stages of life cycles occur in a
number of groups.
 They possess nuclear membranes and mitochondria.
 Nutrition include Photosynthesis, Absorption, Ingestion.
 Reproduction include both Asexual & Sexual
reproduction.

5. CHRYSOPHYTES

6. GENERAL
CHARACTERISTICS.
 Diatoms are microscopic, single
celled forms.
 Cell is called as frustule or shell
 Present in freshwater & salt
water.
 They lack flagella and float
mainly due to light storage lipids
present in them.
 They have cell walls containing
silica, constructed in two
overlapping halves.
 Due to silica impregnations, the
walls are indestructible.
 Outer wall is called Epitheca and
inner wall is called Hypotheca.
 They have fucoxanthin &
chlorophyll and are autotrophic
 They exhibit slow gliding
movements produced by
streaming of cytoplasm.
 Cell wall made of two units hence
the name diatom
DIATOMS & GOLDEN ALGAE-DESMIDS

7. DINOFLAGELLATES

8. GENERAL CHARACTERISTICS
 They belong to the phylum Pyrrophyta of algae.
 Single celled, surrounded by a shell made up of thick
interlocking plates.
 They are motile with two flagella,
 They have the pigments fucoxanthin & chlorophyll.
 Some are parasites ex:-Blastodinium.
 The food reserve is in the form of oils and polysaccharides.
 They occasionally accumulate in large numbers in sea, ex:-
Gonyaulax colouring the water red called as Red Tide.
 Some species are poisionous and can kill aquatic animals
 Some members are Phosphorescent and make the sea
flow in the dark.
 They are covered with cellulosic cell wall which are divided
into plates.
 Method of reproduction is Asexual (Except Ceratium) Ceratium

10. RED TIDE
Gonyaulax

11. Bioluminescence
Noctiluca scintillans

13. GENERAL CHARACTERISTICS
 Unicellular Euglena and its relatives have both animal and
plant characteristics.
 They are advance that Blue-Green Algae, because they
have well stained nucleus and chlorophyll is localied in
Chloroplasts.
 They are free living, found in fresh water ponds, ditches &
damp soil.
 Cell wall is absent, but contain flexible pellicle made up of
proteins.
 All euglenoids have one or two flagella.
 They have red pigmented eyespot, the pigment in the
eyespot is astaxanthin.
 They are photoautotrophic or holophytic
 Chloroplast contain pigments such as chlorophyll a,
chlorophyll b and xanthophyll.
 They store crabohydrates in the form of paramylum.
 Reproduction is Asexual.
 Ex:- Euglena, Paranema, Astasia, Trachelomonas.

17.  The vegetative phase is a free-living, naked,
multinucleated mass of protoplasm called Plasmodium.
 The plasmodium consists of diploid nuclei, lacks cell
wall and secrets slime.
 Chlorophyll is lacking, they are saprophytic, rarely
parasitic.
 They show amoeboid movement by producing
pseudopodia.
 They reproduce by spores produced in sporangia
(fruiting bodies).
 The spores germinate to produce myxamoebae or
biflagellated swarm cells behaving as gametes.
 These swarm cells fuse showing isogamous type of
sexual reproduction.

21.  They are endoparasitic and pathogeneic and spread by
certain vectors. Eg: Trypanosoma, Leishmania, Giardia
intestinalis.
 May contain one or more or upto eight flagella.
 They are heterotrophic and saprozoic in nutrition.
 They show asexual reproduction by longitudinal binary
fission. There is no sexual reproduction
 Ex: Trypanosoma gambiense

22.  Sacrodines are fresh water (Amoeba) or marine
(Polystomella) or endoparasitic and pathogenic
(Entamoeba histolytica).
 Locomotion occurs by temporary finger-like
pseudopodia or false feet e.g, Amoeba
 They are heterotorphic and holozoic in their nutrition.
 Asexual reproduction occurs by either binary fission or
multiple fission. Some forms show sexual reproduction
e.g; Actinophrys.
 They are either uninucleate or multinucleate (Pelomyxa)
Actinophyrs
Amoeba

23.  They are fresh-water (Paramecium) while some are
pathogenic (Balantidium).
 They have cilia for locomotion.
 They are mostly heterotrophic and holozoic in nutrition.
They have a cytostome (cell-mouth) a feeding
apparatus and a cytopyge or cytoproct (cell-anus).
 Digestion is intracellular and occurs in food vacuoles.
 Reproduction is both asexual and sexual. Asexual is by
binary fission and sexual reproduction is by conjugation.
 They have contractile vacuole for osmoregulation.
 They have nuclear dimorphism and contain
 Micronucleus which controls reproduction
 Macronucleus vegetative in function.

24.  All are endoparasitic and pathogenic.
 The organelles of locomotion and food capture are
absent due to parasitic life
 They exhibit heterotrophic mode of nutrition.
 They show alternation of generation between asexual
and sexual generation