Campbell Biology Chapter 28- Protists

Protists

Mostly unicellular eukaryotes.

___ constitute a paraphyletic group, and ___-a is no longer valid as a kingdom

Photoautotrophs

Contain chloroplasts.

Heterotrophs

Absorb organic molecules or ingest larger food particles.

Mixotrophs

Combine photosynthesis and heterotrophic nutrition.

Endosymbiosis

Mitochondria evolved by endosymbiosis of an aerobic prokaryote.

Plastids evolved by endosymbiosis of a photosynthetic cyanobacterium.

Secondary Endosymbiosis

Occurs when a living cell engulfs another eukaryote cell that has already undergone primary endosymbiosis

Apicomplexans

Parasites of animals; some cause serious human diseases.

The apex contains a complex of organelles specialized for penetrating a host

ie. Plasmodium, malaria

Euglena

Use both photosynthesis and absorb or consume other protists or prokaryotes.

Diatoms

Unicellular algae with a unique two-part, glass-like wall of hydrated silica.

____ usually reproduce asexually, and occasionally sexually

Diatomaceous Earth

A soft, crumbly, porous sedimentary deposit formed from the fossil remains of diatoms.

Foraminiferans

A single-celled planktonic animal with a perforated chalky shell through which slender protrusions of protoplasm extend. Most kinds are marine, and when they die, their shells form thick ocean-floor sediments.

Dinoflagellates

a single-celled organism with two flagella, occurring in large numbers in marine plankton and also found in fresh water.

Cause of red tides.

Nourish coral polyps that build reefs

Brown Algea

The largest and most complex algae. "Seaweed"

Algal body is plantlike but lacks true roots, stems, and leaves.

Ciliates

Use of cilia to move and feed

ie. Paramecium.

Alternation of Generations

The alternation of multicellular haploid and diploid forms.

Heteromorphic

Generations are structurally different.

Isomorphic

Generations look similar.

Oomycetes

Include water molds, white rusts, and downy mildews.

Decomposers or parasites.

Phytophthora infestans causing potato blig

Archaeplastida

A supergroup used by some scientists and includes red algae, green algae, and land plants.

Red Algae

Reddish in color due to an accessory pigment call phycoerythrin.

Green Algae

Plants are descended from Green Algae. 2 types: chlorophytes and charophyceans

Chlorophytes

Green Algae; lives in freshwater or marine environments. unicellular such as Chlamydamonas.

Charophyceans

Green Algae; live in damp soil, as lichens or in snow.

Unikonta

Supergroup includes animals, fungi, and some protists.

2 clades: amoebozoans and the opisthokonts

Amoebozoans

includes amoebas with lobe or tube shapes pseudopodia (Tublinids), slime molds (cellular and Plasmodial) and entanameobas (primarily parasites)

Slime Molds

"Mycetozoans"; were once thought to be fungi.

Clade- Amoebozoa

Entamoebas

Parasites of vertebrates and some invertebrates.

ie. Entamoeba histolytica causes amebic dysentery in humans

Opisthokonts

Include animals, fungi, and several groups of protists.

Hypermastigotes

Digest cellulose in the gut of termites.

The SAR clade contains:

Stemenopiles, Alveolates, and Rhizaria

Stremenopiles include:

Diatoms, Golden Algae and Brown Alea.

Alveolates include:

Dinoflagellates, Apicomplexins, and ciliates

Rhizaria Include:

Radiolorians (delicate silika structures, heterotrophic, feed kinda like jellyfish), Forams (pouros shells called tests:both heterotrophic and photosynthetic, marker for age of sedimentary rock), and Cercozoans (kinda boring, flagellates, amoeboid, heterotropic),

Excavates include:

Diplomonads, parabasilids and Euglenozoans

Archeaplastida includes:

Red algae and green algae

Unikonts include

ameabozoans and opisthokonts

Hedrogenozomes belong to

parabasilids

Mitosomes belong to

diplomonads

kinetoplastids

have a large mitochondrian that contains organized mass of DNA called a kinetoplast. cause trypanosoma wich is a neourological sleaping disseas. Part of euglenozoans wich are excavates

Euglenids:

a euglenid has a pocket at one end of the cell from which one or two flagalla emerge. Mixotrophic.

Golden Algea

Cells are typically biflagellated with flagella attached near eachother, components of freshwater and marine plankton

Brown Algae:

the largest and most complex algae, all are multicellular, most are marine, "seeweeds"

Alveolates:

have membrane enclosed sacs: roughly half are purely heterotrophic.

Apicocomplexins:

nearly all are parasites to animals: spread through host as "sporosoites"

Ciliates:

Have ciliated body either all over or in one condensed location