LABORATORIO: PROTOZOANS Animal-like organisms

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LABORATORIO PROTOZOANSAnimal-like organisms

• EJERCICIO 6
• 88-107 (EDITION 14TH)
• 77-102 (EDITION 15TH)

http//www.microscopyu.com/moviegallery/pondscum/
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Goals for today

• Learn to use the microscope
• Learn to recognized the various protozoan phyla.
• Learn their main diagnostic characteristics
• Learn about their biology and their ecological,
  economic, and medical importance

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PROTOZOA
Protozoa is a polyphyletic assemblage of
animal-like organisms. This mean that many
organisms grouped under Protozoa actually evolved
independently, from different ancestors.
Hickmann et al. 2011
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PROTOZOA What they share

• Protozoan organisms have two animal like
  characteristics
• Absence of a cell wall
• Presence of at least one motile stage in the life
  cycle

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PROTOZOA What they dont have

• They dont have organs or tissues BUT have
  division of labor within the cytoplasm
• Various organelles within the cytoplasm function
  as skeletons, locomotory systems, sensory
  systems, conduction, defense, etc.

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PROTOZOA Where can you find them?

• Protozoan organisms are found in a variety of
  habitats
• Free living
• Fresh, marine, and brackish water
• Moist soils
• Parasites
• Symbiotic relationships

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PROTOZOA why are they important?

• Although protozoa are frequently overlooked, they
  are ecologically very important
• As predators of algae, bacteria, and microfungi,
• Herbivores
• Decomposers
• Parasites of great medical and economical
  importance

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PROTOZOA From chaos to order

• Previously they belong to the Phylum Protozoa
  where four main groups were recognized
• Flagellates
• Amebas
• Spore-formers
• Ciliates
• A new classification approach that considers
  PHYLOGENETICS and uses MOLECULES to construct
  their relationships recognizes 14 PHYLA !!!

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PROTOZOA Your Tasks

• Exercise 6A
• Phylum Amoebozoa (naked amebas)
• Species Amoeba proteus

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PROTOZOA Amoeba proteus

• Take a slide from your assigned box
• Look at the Ameba and try to identify the nucleus
  and pseudopodia, contractile and food vacuoles.
• We dont have any parasitic Ameba but learn about
  this species Entomoeba gingivalis, where do you
  think it lives?
• Do the report AMEBA

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PROTOZOA Amebas

• Amebas can be naked or enclosed in shells
• Ameoba proteus is a naked ameba that lives in
  freshwater.
• Usually found in the underside of water plants.
• Feed on algae, bacteria, protozoans, rotifers,
  and other microorganisms.
• They are granulated in appearance

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PROTOZOA Amebas

• Amebas body
• The outer cell membrane plasmalemma
• The plasmalemma encloses the cytoplasm
  ectoplasm endoplasm.
• Amebas Feeding habits
• Phagocytosis engulfing the food
• Note the food vacoules.
• Lysosomes help digestion

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PROTOZOA Amebas

• Amebas locomotion
• Amebas move and change body shape by thrusting
  out pseudopodia.
• Pseudopodia are extensions of the cell body.

INSERT VIDEO OF AMEBA MOVING
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PROTOZOA Amebas

• Amebas excretion
• Any undigested product is eliminated at any point
  of along the plasmalemma.
• Amebas osmoregulation
• Contractile vacuole increases in size and then
  ruptures to the outside.
• This organelle rids the ameba of the excess water
  taken from food or osmosis.
• Amebas nucleus
• Nucleus is disc shaped and finely granulated.

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PROTOZOA Amebas

• Amebas reproduction
• Asexually by binary fission
• Animation http//www.classzone.com/books/hs/ca/sc
  /bio_07/animated_biology/bio_ch05_0149_ab_fission.
  html

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PROTOZOA Your Tasks

• Exercise 6A other Amebas
• Phylum Foraminifera
• Marine shelled amebas
• Secrete a skeleton of 1 or more chambers
• Skeleton Calcareous or silica, sand or sponge
  spicules
• Long delicate pseudopodia
• When died are fall to the bottom of the ocean
  forming enormous limestone deposits

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PROTOZOA Your Tasks

• Exercise 6A other Amebas
• Phylum Radiolaria
• Marine shelled amebas
• Secrete a transparent skeleton of silica
• Slender pseudopodia come through the shell by
  pores

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PROTOZOA Your Tasks

• Exercise 6B
• Phylum Euglenozoa
• Species Euglena gracilis (or viridis)

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PROTOZOA Euglena

• Take a slide from your assigned box
• Look at the Euglena and try to identify the
  nucleus contractile and stigma.
• Do the report Euglena

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PROTOZOA Euglena

• Euglena body
• Euglena gracilis is greenish because of
  chloroplasts that contain chlorophyll.
• Body is covered by a pellicle secreted by the
  ectoplasm
• The stigma or eyespot is a reddish pigment that
  is light sensitive
• Euglena habitat
• Common in still pools and ponds
• Euglena locomotion
• Whiplike flagellum that maybe you can see with
  reduced light

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PROTOZOA Euglena

• Euglena movement
• Euglena gracilis is greenish because of
  chloroplasts that contain chlorophyll.
• Euglena habitat
• Common in still pools and ponds
• Euglena locomotion
• Whiplike flagellum that maybe you can see with
  reduced light
• Watch their movement on live individuals

INSERVE VIDO OF EUGLENA MOVING
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PROTOZOA Euglena

• Euglena osmorregulation
• Contractile vacuole eliminates excess of water
  and waste
• Euglena Feeding
• Photosynthetic
• Carbohydrates are stored as starch granules and
  paramylon (carbohydrate similar to starch)
• Euglena Reproduction
• Longitudinal fission when is free or encysted

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PROTOZOA Your Task

• Exercise 6B
• Phylum Euglenozoa
• Species Trypanosoma

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PROTOZOA Trypanosoma

• Your instructor will try to find Trypanosoma. So
  be patient.
• What diseases are related to this protozoan?
• Do report on Trypanosoma

INSERT VIDEO MONSTER INSIDE OF ME Death by
Tsetse Fly
http//www.youtube.com/watch?v4aVUrGO97Zg
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PROTOZOA Trypanosoma

• Trypanosoma
• Parasite that lives in blood or tissues of
  vertebrates.
• Some species are not parasites
• Trypanosoma Feeding
• Osmotrophic absorbs nutrients directly from
  surrounding blood or body fluids
• Trypanosoma diseases
• Sleeping sickness (T. brucei gambiense, T.b.
  rhodesiense, T. b. brucei).
• Chagas disease (T. cruzei). Darwin was believed
  to have had Chagas disease in his trip to Chile.

Africa Tsetse
Central and South America kissing bug
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PROTOZOA Your Tasks

• Exercise 6C
• Phylum Apicomplexa
• Species Plasmodium

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PROTOZOA Plasmodium

• Your instructor will try to find Plasmodium in
  the slide. So be patient.
• What diseases are related to this protozoan?

INSERT VIDEO Monsters Inside Me Malaria
http//www.youtube.com/watch?vJwsoK8O0lXE
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PROTOZOA Plasmodium

• Plasmodium
• Causes malaria
• 300 million people gets malaria every year.
• 3 million people die every year.
• Two hosts
• Anopheles mosquito (female)
• Human

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PROTOZOA Apicomplexa

• Plasmodium cycle

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PROTOZOA Your Tasks

• Exercise 6D
• Phylum Ciliophora
• Species Paramecium

INSERT VIDEO OF PARAMECIUM
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PROTOZOA Paramecium

• Look at your Paramecium slide
• Look at live Paramecium
• Your instructor will show you a slide of
  Paramecium trychocysts

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PROTOZOA Paramecium

• Paramecium
• Ciliado that inhabits fresh water environments.
• Paramecium movement
• Very active and fast!
• Movement by ciliary action
• Paramecium Body
• Mouthcystostome
• Body cover by a pellicle
• Two nucleus macro micro nucleus

INSERT VIDEO OF PARAMECIUM MOVING
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PROTOZOA Paramecium

• Paramecium osmorregulation
• Contractile vacuole.
• Located at the end of the body
• Paramecium nucleus
• Macronucleus regulates metabolism of the cell
• Micronucleus contains the animal genome and is
  in charge of reproduction.
• Paramecium Trychocysts
• Is a structure under the pellicle that when
  explodes releases a liquid that hardens in water.
• Believed to have a protective function.
• When a paramecium feels threatened, trychocysts
  shoot out from the cell membrane like miniature
  arrows

Discharged trychocysts
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PROTOZOA Paramecium

• Paramecium feeding
• Holozoic feed on particucles e.g., bacteria
• The anal pore (cytoproct) is located between the
  mouth and the posterior end of the body.
• The anal pore is temporary only when food is
  discharged.

Video of Paramecium feeding on Yeast that has
been stain in red
http//www.youtube.com/watch?vl9ymaSzcsdY
Watch the formation of food vacuoles
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PROTOZOA Paramecium

• Paramecium reproduction
• Conjugation
• Binary fission

Conjugation oral grooves are attached
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PROTOZOA Your Tasks

• Exercise 6D
• Phylum Ciliophora
• Species Stentor, Vorticella

INSERT VIDEO OF STENTOR
INSERT VIDEO OF VORTICELLA
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PROTOZOA Vorticella

• Solitary
• Sessile ciliates
• Ponds and streams
• Stalk is long threat-like structure that
  attach it to the substrate.
• Body is bell shape
• Peristoma contains the oral disc.
• Macronucleus is U shape
• Reproduction is by binaary fission and budding

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PROTOZOA Stentor

• Large ciliate
• Live in lakes and streams, only one species is
  marine, and a few terrestrials, some are
  symbiotic with algae
• Large macronucleus that stretch out like a string
  of beads.
• Heterotrophic is an organism that cannot fix
  carbon and uses organic carbon for growth

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PROTOZOA Experiments

• Experiment
• Phototaxis
• Chemotaxis

Your instructor will place protozoans in a petri
dish and under a dissecting scope you must follow
their change in behavior

• Noticed how they move
• Noticed their behavior when you changes of light
  intensity

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Important Links
http//www.savalli.us/BIO385/Diversity/01.Protozoa
.html
http//www.microscopyu.com/moviegallery/pondscum/i
ndex.html
http//www.mcwdn.org/Animals/PROTOZOA.html