Protozoans Flashcards
organism composed of one or more cells containing visible evidence of nuclei and organelles
eukaryote
how did eukaryotes evolve?
cellular symbiosis among prokaryotic cells
When two dissimilar organisms live together and form an intimate and life-sustaining relationship that is mutually beneficial
symbiosis
A cellular organism (such as bacterium or blue-green alga) that does not have a distinct, membrane-bound nucleus.
prokaryote
Apparently, the first cells to appear in the fossil record (3.5 billion years ago) were bacteria-like and prokaryotic/eukaryotic
prokaryotic
____ cells have organelles and a nucleus,
eukaryotic
The origin of complex eukaryotic cells was most likely a type of _____ among prokaryotic cells.
symbiosis
This may have involved aerobic bacteria which were engulfed by anaerobic bacteria that were unable to tolerate the increasing oxygen (anaerobic) in the atmosphere caused by photosynthetic bacteria. These engulfed aerobic bacteria had the necessary enzymes for deriving energy in the presence of oxygen and may have become what organelle found in most modern eukaryotic cells.
mitochondria
Engulfed photosynthetic bacteria evolved into ____; which are the descendants of the green algae lineage, later giving rise to multicellular plants.
chloroplast
a. They lack a cell wall, unlike plants
b. They have at least one motile stage in the life cycle.
c. Most ingest their food.
protozoa
have intracellular specialization or organization of organelles in cells
protozoa
Cells may have distinct functions; some colonial protozoa have separate somatic and reproductive ____.
zooids
Asexual reproduction occurs by ____ in protozoa
mitotic division
have the simplest exoskeletons.
shelled protozoa
obtaining nourishment by feeding on plants or other animals
holozoic
Over 64,000 species are named; half are ____
fossils
Although they are unicellular organisms, protozoan cell ____ are highly specialized
organelles
They can be fantastically numerous, forming gigantic ocean ___deposits
soil
About 10,000 are symbiotic in or on animals or plants; some are human disease agents.
protozoa
Protozoa have only one non-reproductive cell type and lack embryonic development; embryonic development is one of the criteria for
metazoa
They are unicellular with some colonial and multicellular stages.
protozoan phyla
Most are microscopics
protozoan phyla
All ____are present within members of the group
symmetries
3 types of symmetry
spherical
radial
bilateral symmetry
are germ layers present in protozoan phyla?
no
are organs and tissues formed in protozoa?
no
They include free-living, mutualistic, commensal and parasitic forms.
protozoa
They move by pseudopodia, flagella, cilia and they can direct cell movements
protozoa
phylum and subphylum of amoeba
Sacromastigophora
Sarcodina
paramecium phylum and class
ciliophora
oligohymenophora
ciliated protozoan
paramecium
pseudopodia protozoa
amoeba
flagellated protozoa example
euglena
phylum
subphylum
class
euglena
sarcomastigophora
mastigophora
phytomastigophorea
Most are ___, but some have a simple endoskeleton or exoskeleton
naked
Reproduction is asexual by ___, ___or cysts; or sexual by ____coloor syngamy of gametes
fission
budding
conjugation
in phytomastigophorea, pandorina, eudorina, synura, gonium, and dinobryon are ___
colonial
ptychodiscus, ceratium, and clamydomas are ___
dinoflagellates
noctiluca, peranema, and chlomonas have no pigments and are not ___
photosynthetic
colonial flagellate with cells similar to those found in sponges
Codosiga
commonly fouind in gut of termites and wood reoaches, where they help digest cellulose from the wood eaten by insects
Trichonympha
Spirotrichonympha
Trichomonas
parasite of various animals, and some species cause serious disease in humans and domestic animals
Trypansoma
intestinal parasite of mammals that causes diarrhea in humans
Giardia
ameboid marine protozoa that secrete a calcareous, many-chambered test in which to live and then extrude protoplasm through pores to form a layer over the outside
foraminiferans
All of the members of this phylum are propelled by a long whip-like projection
called a flagellum.
phylum zoomastigophora
Almost all of the zoomatigians have one, two, or more
flagella; but in some members, a ____ is lacking
flagellum
are
heterotrophic, and most are free-living, but some are parasitic
flagellates
It is believed
that the first eukaryotic cells were
flagellates
. Because of genetic variation and
natural selection, some of these may have given rise to plantlike organisms while other have evolved into more highly adapted and
specialized animal types.
flagellates
The organisms in this phylum are characterized by having hair-like projections called cilia,
which they use for locomotion and food-getting
ciliophora
have same basic structures as flagella,
but are generally shorter and more numerous than flagella
cilia
they possess two different types of nuclei: a
large macronucleus and one or more smaller micronuclei.
ciliophora
is concerned
with the general control of cell activities,
macronucleus
is involved in sexual
reproduction. Like the flagellates, the ciliates are heterotrophic, a few being parasitic.
micronucleus
reproduce asexually by binary fission; dividing into two equal daughter cells.
ciliates
may also reproduce sexually, allowing for greater genetic variability, through a
process called conjugation.
paramecium
During this process, two individuals come to lie with their ventral
sides together, and a protoplasmic bridge forms between them
conjugation
The macronucleus/micronucleus
disintegrates and gradually disappears.
The macronuclei/micronuclei divide several times and finally the Paramecium exchanges some of their nuclear material.
macronucleus
micronuclei
The members of this phylum move by protoplasmic extensions called
pseudopodia (false feet)
sarcodina
are also important in food-getting. They
surrounded the food and enclose it in a food vacuole in the process known as
phagocytosis.
sarcodina
is a “blob of protoplasms” with no definite
shape
amoeba
have pseudopodia and some have flagellated gametes
sporozoa
The
most widely-known member of the sporozoan phylum is
plasmodium
the blood
parasite which causes malaria in man
plasmodium
is
carried by a secondary host, the female Anopheles mosquito, which transmits
malaria to man
plasmodium
. They typically have a life cycle in which a sexual stage
alternates with a spore-producing asexual stage
sporozoa
develop as the result of
multiple fission of a “mother cell”.
spores
Some are amoeboid and others are
encapsulated
sporozoa
