Phylum Ciliophora - ciliates

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Pellicle is a cell membrane

with alveoli.

Oral groove, cytostome,

cytopharynx, food vacuole,

cytoproct – for digestion.

Contractile vacuole for osmoregulation. (It pumps out water. Think of

how osmosis works and why a freshwater protest would need one.)

Some ciliates have reduced ciliature

and/or modified cilia.

cirrus (-i) are tufts of cilia

fused to form leg-like

structures.

Membranelles are rows

of cilia fused to form

sheet-like structures.

Stentor Euplotes

Vorticella

Cilia and flagella have similar internal structure.

9 + 2 arrangement of microtubules.

9 fused pairs of microtubules on the outside of a cylinder, plus 2

unfused microtubules in the center.

Dynein "arms" attached to the microtubules serve as the molecular

motors.

Flagella (longer and less numerous ) undulate, while cilia (shorter

and usually more numerous) move in an oar-like fashion.

phylum Bacillariophyta - diatoms

The cell wall is a 2-part, silicious frustule.

One valve fits inside the other. When cells divide, each daughter cell forms a new

valve to fit inside the old one, so some cells are smaller. They get smaller and smaller

until, at 1/3 original size, they reproduce sexually and return to full size.

These unusual algae (photosynthetic) occurred in large numbers in the past (blooms)

in places where their remnant frustules formed layers of diatomaceous earth (now

used as water filters and polishing compounds, including tooth paste.)

phylum Phaeophyta – brown algae

these marine algae are often very large, like kelp and

sargassum, and have a simple, multicellular form.

They have zones of growth, called meristems.

phylum Rhodophyta – red algae are deep-water,

marine macroalgae. Their pigments are suitable for deep water. Some

are edible and provide useful products, like carrageenan (used in ice

cream), nori, and agar.

Ameboid protozoaAmebas – with and without tests (shell-like structures)

Pseudopods are used for movement and phagocytosis

Pseudopod movement involves a thick ectoplasm and a thin

flowing endoplasm. Cytoskeletons break down and rebuild as

one converts to the other.

Lobopodia are blunt and lobe-like.

phylum Gymnamoeba“naked” amoebae,

without tests.

Some are parasitic

and some are

free-living.

phylum Radiolaria

axopodia and silicious tests with perforations.

Axopodia are pseudopods reinforced with

microtubules – stiff and needle-like.

phylum Foraminifera

reticulopodia and chambered, calcareous tests.

Reticulopodia are threadlike and branching

pseudopods.

Ancient oozes of foraminifera formed

the White Cliffs of Dover and pink

sands of Bermuda. Some of them are the

largest protists ever lived.

phylum Myxomycota – plasmodial slime molds

The body form is a

plasmodium –

a multi-nucleate mass

of protoplasm

complex life cycles include spore formation

phylum Chlorophyta – green algae

cell walls and

chloroplasts

solitary or

colonial

phylum Choanoflagellata

collar cells adapted for filter-feeding a collar of

microvilli and a

single flagellum

These protists are more closely related to Animalia

than any other group. They are considered to be a sister group of kingdom Animalia.