Domain Eukarya

Cell type: Eukaryotic

Cell wall: Present in

some (as cellulose or

chitin), absent in some

Domain Eukarya

Mode of Nutrition:

autotrophs,

heterotrophs, or both

Reproduction: asexual,

sexual, or both

Habitat: Diverse

Kingdom Protista

It is actually an

obsolete term that

describes plant-like,

animal-like, and fungus-

like organisms

(mainly unicellular).

Kingdom Protista

Today, this term is not

preferred by biologists

because they have

shown that these

organisms are either

plants, animals, fungi,

or belonging to their

own unique group.

Kingdom Protista

Autotrophs (Algae)

Heterotrophs w/o Cell Walls (Protozoa)

Heterotrophs with Cell Walls (Slime Molds)

Autotrophs / Plant-like Protists

Algae

Structure:

• Eukaryotic

• Unicellular or multicellular

organisms

• Have chlorophyll as the main

pigment for photosynthesis

• No true roots, stems, or leaves

Algae

Mode of nutrition

• Most are autotrophic (some

are both autotrophic and

heterotrophic)

Reproduction

• Sexual and asexual

Ecological Importance

• PRODUCERS of aquatic

habitats

Groups of Algae

•Green Algae (Chlorophyta)

•Red Algae (Rhodophyta)

•Brown Algae (Phaeophyta)

•Dinoflagellates (Dinoflagellata)

•Euglenids (Euglenophyta)

Green Algae

• Contain chlorophyll in their chloroplasts

• Some have cell walls made of cellulose

• Most scientists today consider them as plants

• Has unicellular and multicellular forms

• No true roots, stems, or leaves

Chlorella

• Unicellular green algae

• High in protein and other nutrients – used in food supplements

• Excessive growth can sometimes cause problems in lakes,

aquaria, etc.

Red Algae

• They are red because of the pigment phycoerythrin

• Mostly live in the ocean – seaweeds

• Source of carageenan and agar – gels that can be used for a

variety of purposes

Gulaman or agar-agar

Gelidium corneum

Nori

Porphyra sp.

Brown Algae

• They are brownish because of the pigment fucoxanthin

• Mostly live in the ocean – seaweeds

• Largest and the fastest growing of all seaweeds

• Can be a food source

Sargassum sp.

Giant KelpMacrocystis pyrifera

Dinoflagellates / Pyrrophyta

• Unicellular organisms that could do photosynthesis though some

combine photosynthesis and ingesting food

• Excessive growth (Algal bloom) causes death of marine

organisms

Harmful algal bloom (red tide) caused by dinoflagellates –

Pyrodinium bahamense

Euglenids

• Unicellular organisms with

chloroplasts and flagella

• When there enough light, they

are autotrophs. When there is

insufficient light, they become

heterotrophs.

• They are positively

phototactic.

Euglena sp.

Heterotrophs without cell walls / Animal-like Protists

Protozoa

• A DIVERSE group

of unicellular eukaryotic

organisms.

• They are heterotrophic - they rely

on the environment and other

organisms for their nutrition.

• They DO NOT HAVE

chlorophyll.

Importance

• Protozoa are commonly prey

so they are an important food

source.

• As predators, they

eat unicellular algae, bacteria,

and microscopic fungi.

• Protozoan species include both

herbivores and consumers in

the decomposer link of

the food chain.

Amoeba

• A type of cell that can

alter its shape.

• They have pseudopodia

(pseudopods – false feet)

• Mostly Unicellular and

heterotrophic.

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Trypanosoma

• - Unicellular parasite.

• - Flagellate protozoa

• - In invertebrate host they are found in the intestine, But

in mammals they are commonly found in the

bloodstream.

• - Causes Sleeping sickness.

Plasmodium

• - Commonly known as malaria parasite

• - a large genus of parasitic protozoa

• - It is heterothopic.

• - it causes Malaria : a lethal diseases usually found in tropical

regions.

• - It has 2 host in this life cycle: a human or a mosquito vector.

Plasmodium spp.Causative Agent of Malaria, the most important parasitic

disease worldwide

Paramecium

• - A genus of unicellular ciliated

Protozoa.

• - commonly found freshwater,

brackish and marine

environments.

• - used in labs as test subject

• - also called as white rat.

Leishmania

• - A genus of parasitic protozoa.

• - responsible for the disease Leishmaniasis.

• - commonly infects rodents, humans and canids

• - Leishmaniasis is commonly carried by sandflies.

• - Leishmaniasis is a disease that causes skin ulser.

Cutaneous Leishmaniasis

Mucocutaneous Leishmaniasis

Visceral

Leishmaniasis/

Kala-azar

Heterotrophs with cell walls / Fungus-like Protists

Slime Molds

Phylum Myxomycota

• Fungus-like organisms that are

consumers

• feed on bacteria growing on rotting

logs and decaying leaves.

• Their cell wall is made up of chitin

Slime Molds

If conditions become

uncomfortable—not

enough food available, the

temperature isn't right,

etc.—individual cells begin

gathering together to form

a single structure.

Water Molds

Phylum Oomycota

• Water molds have flagellated

reproductive cells.

• Downy mildews parasitize plants

and are decomposers in

freshwater ecosystems.

• Their cell wall is made up of

chitin.