This document provides information on the major protist groups, including Chromalveolata, Excavata, Rhizaria, Archaeplastida, and Unikonta. It describes key characteristics of each group such as their cellular structure, organelles, methods of movement, and important examples of protists within each group. The document aims to classify and describe the major lineages of protists.

1. MAJOR
GROUPS:
PROTIST’S
Domain: Eukarya Kingdom:
Protista

2. Chromalveolata
 To determine if a protist species is a part of this phylum
is based on two pieces of confirmation. First of all, some
of the DNA sequence data propose that this phylum
forms a monophyletic group. It also needs to be proved
that the Chromalveolata phylum was established over a
billion years ago.
 The ancestral species of this phylum is thought to be red
algae.

3. Chromalveolata Continued
 Alveolata: Alveolates are a group of protist’s whose
monophyly is well supported by molecular systematic. Alveoli
are membrane-bounded sacs, in the plasma membrane.
Scientist has researched the use of the alveoli but have come
to no conclusion as to why it exists.
o Dinoflagellata: Characterized by cells that are reinforced by
cellulose plates. They are mechanisms of both marine and
freshwater plankton. Some of the most important
photosynthetic species. These heterotrophs contain toxins
have caused many mass murdering throughout the
invertebrate.
o Apicomplexa: Parasites of animals and some cause
serious human disease. They spread through their hosts
as tiny infectious diseases. Apicomplexans obtain a group
of organs that manage the creation of tissues and strong
host cells. Most of the protists in this group have both

4. Chromalveolata Continued
 Stramenopiles: This is a group of marine algae that also
includes some of the worlds most photosynthetic organisms.
Stramenopiles main characteristic is the flagellum that each
protist has. In most protists in this phylum, the hairy flagellum
is paired with a short smooth flagellum.
o Diatoms: Diatoms are unicellular and are producers of
the food chain. These organisms have a cell wall that
is made of silica. There about 200 living species of
diatoms.
o Golden Algae: The main characteristic of golden algae
is their color which comes from yellow and brown
carotenoids. Golden algae does contain both flagella
at one end of the protist.
o Brown Algae: Most organisms in this very complex
group are multicellular. These protists have leaf-like
blades and have specialized tissues and organs.
o Oomycetes: Oomycetes were previously classified as
fungi, until it was determined all the differences
between fungi and Oomycetes. They have cells walls
made of cellulose and do not undergo photosynthesis.

5. Excavata
 Excavata organisms are unicellulr eukaryotes.
Some are missing mitochondria while others have
mitochondria with internal divisions so cellular
respiration can occur.
 Euglenozoans: These are the most important
parasites. Most have two flagella and chloroplasts that
are surrounded by membranes.
 Diplomonads: Most diplomonads are double cells,
meaning they have two nuclei and four flagella. They
lack mitochondria and a golgi apparatus.
 Parabasalids: Parabasalids possess a reduced
mitochondria. They create some energy anaerobically
and discharge hydrogen gas as a by-product.

6. Rhizaria
 Rhizaria consists on mainly species of amoebas which are a
tread-like shaped organism. The amoebas can create
swellings or lumps on any potion of a cell. The knots help with
the capture of prey and are involved in the movement of
these species.
 Radiolarians: These organisms have symmetrical skeletons
made up of silica. The pseudopodia of the protists radiate from
the central body and are resistant because of the microtubules.
 Forams: Foraminiferans are known for their shells, also called
tests. Some forams are capable of receiving nutrients out of their
tests.
 Chlorarachniophytes: Chlorarachniophytes participate in
photosynthesis and capture prey by connecting cells together to
form a net. Also, they have one flagellum, depending on the
species.

7. Archaeplastida
 This group includes red, green algae, and land
plants. Red algae and green algae include
unicellular species, colonial species, and
multicellular species. These protists have a
special photosynthetic species that are the base
of the food web in some habitats.
 Rhodophyta: This is the oldest group of eukaryotic
algae. Red algae are multicellular and are missing
centrioles and flagellas and other important parts.
They receive their red color from a red pigment.
 Land Plants: Land plants established from green
algae but have many similar qualities to the red and
green algae.

8. Archaeplastida Continued
 Green Algae: Green algae has a
good structure and pigment
chloroplasts , similar to those of land
plants. Most cells contain two flagella
and are unicellular.
o Chlorophytes: The old classification of
Chlorophytes was including all the
green algae within the green plants.
The newer classification includes the
two clades that created the
Viridiplantae.
o Charophyceans: This is the closest
group to land plants. Depending on
the organism, a cell may or may not

9. Unikonta
 These eukaryotes includes amoebas that have lobe or
tube-liked shape pseudopodia. It is suggested that
Unikonts might have been the first group of eukaryotes
to diverge from other eukaryotes, but this idea is still
unknown.
 Amoebozoans: Amoebas have a tube-shaped
pseudopodia.
o Slime Molds: They were thought to be fungi in the
beginning, but researchers soon realized that was a
mistake. Molds grow in masses and tends to their
pseudopodia by consuming food particles.
o Gymnamoebas: These unicellular protists feed on
bacteria, other protists, and some organic matter.

10. Unikonta Continued
 Opisthokonuts: A common
characteristic that all eukaryotes
in this group have is a single
posterior flagellum.
o Nucleariids: These organisms
contain scales and or spines.
o Fungi: Eukaryotic species are
similar to some protist because
they grow by repeated cell division.
(same with animals)
o Animals: They are eukaryotic and
multicellular organisms.
o Choanoflagellates:
Choanoflagellates possess a
posterior cilia.