Zoology Lab Exam Flashcards
What are protists?
Unicellular
Found in different habitats (ponds to blood)
Vary in morphology, physiology, and behaviour
Formally assigned to Protista but actually do not form a monophyletic clade
What does the term protozoan mean?
Convenient way of grouping together single-celled organisms, but not a taxonomic level of classification
What is a convenient way of categorizing protozoans ?
By functional group
according to their mode of nutrition or locomotion
What are the four functional categories?
Flagellated
Amoeboid
Spore-forming
Ciliated
What are the FOV diameters for the 4X,10X,40X, and 100X objective?
- 5mm(4500pico metre)
- 8
- 5
- 2
Amoeboid protozoans?
Phylum Rhizopoda
- no shells
- locomote with pseudopodia(falsefeet)
- use membrane-bound extensions of cytoplasm (vacuoles) to feed (endocytosis)
- water and waste excreted by vacuole
- freeliving and parasitic
What two amoebas under Phylum Rhizopoda did we see?
Entamoeba histolytica
Amoeba proteus
Entamoeba histolytica
- parasitics
- large intestine of vertebrates (humans as well))
- feed on rebloodcells and tissue
- amoebic dystensery(severe diarrhea and dehydration)
- highly-resistant encysted form (survive enviro in dormant state until ingested)
- nuc divission in cyst
- trophozoite(active feeding form)
What Entamobea histolytica
adult, and encysted
Amoeba proteus
- feeliving
- freshwater
- bacteria algae, other protists
What Amoeba proteus
wholemount
Flagellated protozoans?
Phylum Euglenoza and Phylum Diplomonada
-single flagellum or multiple flagella
(outgrowth of cell membrane, anchored within basal body)
-sometimes joins body to form undulating membrane
-SOME parasitic species
What ex. of Flagellated protozoans: Trypanosoma brucei
-Phylum Euglenoza
-“sleeping sickness”-in Africa, affect human and livestock
_within blood stream
-through Tse Tse fly bite
-dark-staining kinetoplast(circular DNA w/ many copies in mitochondrial genome) within mitochondrion
What Trypanosoma brucei
bloodstream(trypomastigote)
What ex. of Flagellated protozoans: Giardia sp.
Phylum Diplomonada
- “beaver fever” wildlife = imp reservoir of infection
- release cysts into environment while humans consume
What Giardia sp.
Giardia lamblia adult stage (tryphozoites)
G. lamblia (cyst in fecal matter)
Spore-forming protozoans?
Phylum Apicomplexa
-parasitic
-apical complex (aids entry into host cell)
-2 different hots to complete lifecycle
-spore-forming b/c INFECTIVE STAGE = sporozoite
MORE FAMOUS: Plasmodium - Malaria
Life cycle of human malaria
Infected mosq injects sporozoites while feeding
Stops at liver, penetrated red blood cell (merozoites, asexual cycle)
-Gametocytes
-Transmission to mosq
What spore-forming protozoans?
Plasmodium falciparum (trophozoites)
How does the slide appear for the spore-forming protozoans?
Nuc = red
Cyto = blue
in ring-shaped TRYPHOZOITE
(asexual reprod in red blood cells)
Ciliated protozoans?
Phylum Ciliophora
-cilia structurally identical to flagella
humans may have ciliated cells as well (nasal cavity and trachea have)
also used for feeding
-MORE FAMOUS: Paramecium
-MORE STRUCTURALLY COMPLEX THAN AMOEBAS
-ciliates have macro and micro nucleus
What ciliated protozoan?
Stentor sp.
macronucleus has “beaded appearance”
How do protozoans locomote?
Alter shape and thrusting out projections os cytoplasm (pseudopodia) - contractile protein fibers within ytoplasm
What is a type of green algae?
Chlorella as food source for amoeba
Where is Euglena common found in?
Ponds and streams
Euglena is a
MIXOTROPH, LEAF-LIKE SHAPE
What is a mixotroph?
Generating its own food when there is sufficient sunlight(mix of plant and animal)
What does the stigma do?
beside basal body, detects light intensity
What is Lugol’s solution
Iodine and Potassium, kills and stains Euglena
How is food digested?
Enzymes secreted from cytoplasm
Into food vacuoles
(ph to acidic or alkaline mediums (on enzymes), or pH)
What do we feed the ciliated protozoans?
Yeast and Congo red dye
Congo red is clue in strong acid solutions (3 or less)
Red in less (5 and up)
Can you distinguish anterior from posterior in ciliated protozoan?
no
