5.1. Animal-Like Protists Flashcards
most protists are multicellular, and all are eukaryotic. True or false?
False. unicellular
Protists are more nutritionally diverse. True or false?
TRUE
All protists can undergo ____ reproduction by mitosis (generally by ____), yet many are able to undergo sexual reproduction through a combination of meiosis and ___
asexual; simple fission; nuclear exchange
protists also can form _____that allow them to lie dormant for long periods of time
cysts
Protists are most certainly ___ ,meaning all modern protists do not share the most recent common ancestor
polyphyletic
Euglenozoa: Euglenoids & ______;
Alveolata: Dinoflagellates, _____ & Ciliates;
_____: Amoebas & Choanoflagellates
Kinetoplastids
Apicomplexans
Unikonta
____are unicellular, motile flagellates that reproduce asexually by binary fission and possess flexible cell membranes.
Euglenozoans
characteristic feature of _____ is an anterior pocket that bears one or two flagella extending from the reservoir in the anterior end of the organism
Near the base of the primary flagellum is a pigmented ____ that serves as a photoreceptor,
euglenoids;
eyespot
unicellular, parasitic flagellates characterized by a single, large mitochondrion containing a kinetoplast.
Kinetoplastids
a unique organelle that houses extra nuclear DNA;
characteristic feature of Kinetoplastids
kinetoplast
monophyletic clade of protists (a superphylum within the Chromalveolata)
Alveolata
What are the three Sub-phyla of Aveolata?
Dinoflagellates, Apicomplexans & Ciliates
- among the most important primary photosynthetic producers of organic matter in the oceans.
- mostly marine, unicellular autotrophs
- two perpendicular grooves
- internal cellulose plates.
- primary photosynthetic pigment is chlorophyll C.
- often cause red tides
Dinoflagellates(Phylum Dinoflagellata)
- are unicellular parasites characterized by an apical complex of organelles
- nonmotile, they are highly specialized for their parasitic lifestyle.
Apicomplexans(Phylum Apicomplexa)
Apicomplexans(Phylum Apicomplexa) are also known as ___
sporozoans
- unicellular heterotrophs that possess cilia for locomotion and feeding
- have two types of nuclei (______)
- completely covered by cilia (____)
- cilia are clustered into a few rows along the body (_____)
- Using their micronuclei, ciliates undergo an elaborate process of sexual gene shuffling called _____—a process we will examine more closely in Paramecium.
Ciliates (Phylum Ciliophora) micro and macro Paramecium Vorticella conjugation
In paramecium:
Asexual reproduction is through ____, while
Sexual reproduction is _____
Binary fission
conjugation
(Paramecium)
During this asexual process the micronucleus divides by mitosis, while the macronucleus and remainder of the original cell simply
split in half to produce two genetically identical
daughter cells.
Binary fission
(paramecium)
two individuals align longitudinally and attach temporarily. The micronuclei in each cell
undergo meiosis, creating four haploid micronuclei per parent micronucleus(ciliates often have more than one micronucleus).
Conjugation
-a sessile, stalked ciliate commonly found in stagnant bodies of freshwater remains attached to aquatic vegetation by a contractile stalk and possesses a funnel shaped cell body with a ring of cilia around the larger peristome (open end)
Vorticella
_____
This group of eukaryotes includes many specialized protists
Animals, fungi, and a few protist groups are collectively grouped together as ____
Unikonta; Opisthokonts
- unicellular heterotrophs that lack cell walls.
- highly specialized protists
- have flexible plasma membranes that form _____—cytoplasmic extensions used for feeding and locomotion.
- lack the ability to reproduce sexually, and instead, reproduce by ___
Amoebas; pseudopodia; binary fission
_______is one of many species of protists that can form a cyst by secreting a proteinaceous cell wall around itself and entering a state of ____. In the ____ stage, amoebas can survive prolonged periods of dryness and can even be dispersed by wind.
Entamoeba histolytica; dormancy; cyst
Amoebas engulf their food by a process called ____ in which extensions of the plasma membrane (pseudopodia) elongate and surround the food item.
phagocytosis
One lineage of protists in the supergroup Unikonta occupies a very special position in the evolutionary tree of life
are sessile, aquatic organisms (either solitary or colonial) with each cell bearing a single flagellum surrounded by a thin collar
Choanoflagellates
most likely ancestor of sponges
choanoflagellates
The ____ derive their group name from the “excavated” feeding groove that runs along one side of the cytoskeleton of the cell body.
Excavata
(Paramecium anatomy)
-stiff outer covering that maintains basic cellular shape
pellicle
(Paramecium anatomy)
hairlike projections used for locomotion and feeding
cilia
(Paramecium anatomy)
organelle containing many copies of a few genes; primarily controls metabolic processes of cell
macronucleus
(Paramecium anatomy)
typical eukaryotic nucleus containing entire genome; essential for genetic recombination
micronucleus
(Paramecium anatomy)
lateral depression into which food is swept by ciliary currents
oral groove
(Paramecium anatomy)
tubular invagination lined with cilia where food enters and food vacuoles form
cytopharynx
(Paramecium anatomy)
small, spherical organelle containing enzymes to digest food
food vacuole
(Paramecium anatomy)
one or more spherical organelles that pump out water to maintain the internal osmotic balance of the cell
contractile vacuole
(Paramecium anatomy)
site where indigestible matter is expelled from the cell
anal spot (cytoproct)
All members of this group (alveolata) of unicellular protists have small cavities under their cell surfaces called ____.
alveoli
In ciliates, the alveoli produce ____
In _____, the alveoli serve a structural function
in the dinoflagellates, the alveoli produce ____.
pellicles
parasitic apicomplexans
thecal plates
Sessile protist with single flagellum surrounded by collar
choanoflagellate
unicellular heterotroph that moves using pseudopodia
amoeba
unicellular heterotroph with two types of nuclei
ciliate
nonmotile parasite with penetrating apical region
apicomplexan
flagella arise from grooves in cellulose plates
dinoflagellates
unicellular parasite with one large mitochondrion
kinetoplastids
flagella arise from anterior pocket
euglenoid
