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Home , Amoeba (genus), Bacteria, Ceratium, Microorganism, Paramecium, Protist

INTRODUCTION All that can't be classified as , , Fungi, Archea, or are placed in the Protista. All Protista are they possess a nucleus and other internal separated by membranes (membrane-bound ). Here the similarity among protists ends – members of this group can be unicellular (organisms consisting of only one ), colonial (groups cells with some interdependence), or multicellular (composed of many cells with coordinated metabolic activity, may form tissues), autotrophic or heterotrophic. Here is a review of the basic classification system used for all living organisms: of Cell Kingdom Example Prokaryotic Not Used Prokaryotic organisms found in extreme environments Prokaryotic Bacteria Not Used common bacteria, Eukaryotic Eukarya Protists , , , Eukaryotic Eukarya Fungi mushrooms, , Penicillium Eukaryotic Eukarya Animals vertebrates, insects, , Eukaryotic Eukarya Plants , , redwoods, flowering plants There are of protists that are over 2 billion old, and protists have evolved and diversified since that . attempt to classify these organisms according to their evolutionary relationships using evidence from the record, DNA, RNA and other cell structures. The result of this work has led to the proposal of alternative classification systems that may divide the Kingdom Protista into several in the future. For our purposes we will divide the protists according to their mode of (how they obtain their and ) rather than evolutionary relatedness. The are heterotrophic protists that ingest their , and are single-celled or colonial. Algae are all photosynthetic autotrophic organisms, these may be unicellular, colonial, or multicellular (filaments or sheets).

GOALS AND OBJECTIVES 1. Know the meaning and examples of the vocabulary highlighted in bold. 2. Understand the composition of the Kingdom Protista. What are the main phyla within the Kingdom? 3. Be able to identify the of each you observe in lab. 4. Know the special characteristics of each phylum. 5. For each Protist know the method of acquiring food/energy. If the is photosynthetic, know the involved. 6. Know the means of locomotion for each type of motile protist. 7. Know the in which each organism is found. 8. Understand the difference between single-celled, colonial, and multicellular.

10.09 5A-1 KINGDOM PROTISTA

HETEROTROPHIC PROTISTS

PHYLUM – Paramecium characteristics: single-celled protists that move by means of cilia. Ciliates, like Paramecium, are heterotrophic and take food into their cell through an oral groove; once inside the cell a food forms.

PHYLUM AMOEBOIDS – Amoeba. characteristics: single-celled protists that move by means of pseudopods, this type of movement causes the shape of an Amoeba’s cell to constantly change. Food is engulfed by pseudopods forming a .

AUTOTROPHIC PROTISTS PHYLUM EUGLENOIDS – Euglena. characteristics: single-celled protists that possess (containing chlorophyll) and can live either as or . Euglena moves by means of flagella; their flexible body also allows them to slowly undulate along surfaces. The Euglena seen in our lab is primarily autotrophic.

PHYLUM – characteristics: single-celled that are important primary producers in freshwater and marine environments. Most possess chloroplasts containing chlorophyll and a yellow-brown accessory , but some are heterotrophic. Dinoflagellates have a that consists of overlapping armored plates. They move by means of two flagella, one of which wraps around the center of the cell.

PHYLUM - Diatoms characteristics: single-celled plankton that are important primary producers in freshwater and marine environments. Like dinoflagellates, they possess chloroplasts containing chlorophyll and the accessory yellow-brown pigment. The cell walls of diatoms are made of sculptured silica (glass). Most are non-motile, but a few are able to glide along surfaces.

PHYLUM – , Spirogyra, lettuce characteristics: single-celled, colonial, or simple multicellular organisms whose green color is the result of the pigment chlorophyll. Green algae are important primary producers in freshwater and intertidal . They can be non-motile, or motile by means of flagella. Cell walls contain cellulose. Green algae are the most likely of plants.

PHYLUM – , coraline red, Microcladia characteristics: multicellular marine organisms that range from filaments to blade-like sheets. They tend to be reddish in color due to an that masks the primary chlorophyll. This accessory pigment allows them to grow in deeper than other algae. Cell walls contain cellulose. Red algae are non-motile.

10.09 5A-2 PHYLUM – characteristics: large multicellular, marine organisms that have specialized tissues that forms a blade (), holdfast (anchors to substrate), and stipe (connects blade to holdfast, especially important in deep water off the coast), some also have a bladder (floatation). They tend to be brownish in color due to an accessory pigment that masks the primary photosynthetic pigment chlorophyll. Cell walls contain cellulose. Brown algae lack motile adult stages.

REVIEW OF SPECIMEN PREPARATION AND USE Cultures of living specimens are placed on the side bench for you to examine under the compound microscope. Make wet mounts, cover with a coverslip, and bring back to your station for observation. Some specimens will also be available as prepared slides. You may want to base your drawings on these.

Remember the following steps when using compound :  Always start with the 4X objective and the stage at its lowest position  Center your slide over the condenser lens and move the stage to its highest position  Lower the stage slowly using the coarse focus knob while viewing your slide until objects come into focus  Use the stage ( X and Y) control knobs to move your slide in sideways if you do not see anything in the of view  When your specimen is focused you may switch to higher magnification  NEVER use the coarse focus knob at 10X or 40X!

10.09 5A-3 Heterotrophic Protists – Protozoa There are three categories of heterotrophic protists based on their mode of locomotion. Some organisms use extensions of their and called . These pseudopods (“false-feet”) are used in locomotion in Amoeboids; they also surround food and form a food vacuole. Other protozoa use thin, long whip-like organelles called flagella. Flagella are used for locomotion in , Euglenoids, Dinoflagellates, and some green algae. The number of flagella may be one, two, or many. Still other protozoa use short, cylindrical organelles called cilia. Cilia, although shorter and more numerous, are similar in construction to flagella. Paramecium is an example of a Protist that uses cilia for locomotion.

Observation 1: Phylum Ciliates – Paramecium There are many, unicellular ciliates living in freshwater environments. These heterotrophs can be very small and tend to move very rapidly by means of cilia that cover the surface of the cell. A. Make a wet-mount of a flat slide from the culture on the side bench. The Paramecium looks like dust specks to the naked eye. Add a drop of methyl cellulose to slow down the . B. Observe under the compound microscope. Draw a picture of a Paramecium indicating the relative size you see in the circle below. You may be able to observe the formation of food as the Paramecium consumes the . In addition you may observe the action of the which is involved in osmotic regulation.

Kingdom: ______

Phylum: ______Objective Lens: ______Total Magnification: ______

10.09 5A-4 1. What type of does Paramecium use for movement?

2. Is Paramecium autotrophic or heterotrophic?

3. Describe how Paramecium obtains nutrients.

4. What is the name of the channel through which the food enters this organism?

5. What is the natural habitat of Paramecium?

C. Label the cilia, plasma membrane, oral groove, food vacuoles and the contractile vacuole on the Paramecium drawing. (Use your textbook or previous lab activities if you need help.)

Paramecium Observation 2: Phylum Amoeboids – Amoeba

10.09 5A-5 Amoeba belongs to a diverse group of Amoeboids that use pseudopods for locomotion and/or feeding. Most are harmless heterotrophs that engulf food by , one type is a parasite that causes amoebic if swallowed. Amoeba are a freshwater amoeboid, other Amoeboids (Radiolarians and Foraminiferans) may live in . C. Observe the culture dish of Amoeba on the side bench. The Amoeba will appear to be little white specks on the bottom of the jar. D. Using a deep-well slide make a wet-mount from the culture (be sure to completely fill the depression in the slide with liquid). Cover with a coverslip. E. Observe the Amoeba using the compound microscope. 1. Describe the body shape.

2. What structure(s) does an Amoeba use for movement?

3. Are Amoeba autotrophic or heterotrophic?

4. How does an Amoeba ingest its food?

5. What is the natural habitat of an Amoeba?

F. The circle below represents what you would see through the microscope. Draw a picture of an Amoeba indicating the relative size you see in the circle. Label the plasma membrane, cytoplasm, and a pseudopod. (Use your textbook or the boards if you need help.)

Phylum: ______Objective Lens: ______Total Magnification: ______

10.09 5A-6 Observation 3: Phylum Euglenoids – Euglena Euglena are a single-celled protist that moves by means of flagella and is found in -rich (polluted) water. Containing chloroplasts, Euglena are able to use chlorophyll to photosynthesize in the , but they can also absorb nutrients. They lack a cell wall and are surrounded by a flexible pellicle that protects them while allowing for flexibility. A. Make a wet-mount on a flat slide from the culture on the side bench. Cover with a coverslip. B. Observe the Euglena using your compound microscope at 4X, 10X and then 40X. 1. What type of structure does Euglena use for movement?

2. Is Euglena autotrophic or heterotrophic?

3. What pigment is involved in photosynthesis?

4. What is an alternative feeding strategy that Euglena can use in the absence of light?

5. What is the natural habitat of Euglena?

C. Label the , plasma membrane, and chloroplasts in the Euglena drawing. (Use your textbook or the boards if you need help.)

Euglena

D. Draw a picture of Euglena indicating the relative size you see in the circle below.

Phylum: ______Objective Lens: ______Total Magnification: ______

10.09 5A-7 Autotrophic Protists - Algae

There are many different types of algae that differ according to their body form, the type of photosynthetic pigments they use and variations in their flagella. There are several possible forms, these include unicellular, colonial and filamentous organisms. Unicellular algae only have one cell. Colonial algae are temporary clusters of cells that can be organized, but each cell is an individual organism that can break off and survive on its own. Filamentous algae have many interconnected cells that form a long line of cells – a filament; these are a true multicellular form. There are also some multicellular algae that form highly branched structures, others form flattened sheets. In multicellular alga the tissues are simple and do not show much (if any) specialization.

.Observation 4: Phylum Dinoflagellates – Ceratium (Optional –determined by instructor) Dinoflagellates are bi-flagellated, single-celled plankton in freshwater and marine habitats. They contain chlorophyll (the primary photosynthetic pigment) and a yellow-brown accessory pigment (fucoxanthin). Periodically dinoflagellates become extremely numerous and create “algal blooms” known as red . During red tides produced by dinoflagellates accumulate in shellfish and them to be quarantined. Dinoflagellates also can be bioluminescent (give off light); when this occurs the waves and disturbed sand give off a greenish glow. A. Obtain a prepared slide of Ceratium and examine it under the compound microscope with the 4X, 10X, and then 40X lens. 1. What type of structure does Ceratium use for movement?

2. Is Ceratium autotrophic or heterotrophic?

3. What is the cell wall made of?

B. Label the cell wall and flagella in the Ceratium drawing. 4. What is the ecological importance of dinoflagellates in freshwater and marine environments?

5. What is a red ? What is its significance?

6. What is ?

7. To what phylum does Ceratium belong? Observation 5: Phylum Diatoms Diatoms are single-celled, photosynthetic marine and freshwater plankton. Like all photosynthetic organisms they use chlorophyll to capture but they also have the yellow-brown accessory

10.09 5A-8 pigment (fucoxanthin) that aids photosynthesis and gives them their golden color. Most are non- motile, but a few are able to glide along surfaces. A. Obtain a prepared slide of diatoms and examine it under the compound microscope with the 4X, 10X, and then 40X lens. 1. Describe the cell wall of diatoms. What is the cell wall made of? What makes it unique?

2. What pigments are present in diatoms?

B. Draw at least 2 diatoms with different shapes from the prepared slide. You may make a wet mount if material is available.

Phylum: ______Objective Lens: ______Total Magnification: ______

3. In what natural habitat(s) are diatoms found?

4. Are diatoms autotrophic or heterotrophic?

5. In what two ways are diatoms ecologically important?

10.09 5A-9 Observation 6: Phylum Green Algae – Spirogyra Green algae are found in most habitats. Members range from unicellular, to colonial, to filamentous, to blade-like. All contain the green pigment chlorophyll that is primarily responsible for photosynthesis. The colonial Volvox and filamentous Spirogyra are both found in ; the blade-like forms, such as Ulva, are marine . A. Make a wet-mount of Spirogyra on a flat slide from the culture on the side bench. Cover with a coverslip. B. Observe using the compound microscope. C. Label the cell wall, , and cytoplasm on the Spirogyra drawing.

Spirogyra

1. What type of form does Spirogyra have (filamentous or colonial)?

2. Is Spirogyra autotrophic or heterotrophic?

3. What primary pigment is involved in photosynthesis? Describe the shape of the chloroplast.

4. What is the cell wall made of?

5. Is Spirogyra motile?

6. To what phylum does Spirogyra belong?

7. What is the natural habitat of, and what is the ecological importance of Spirogyra and other filamentous alga?

10.09 5A-10 Observation 7: Phylum Green Algae – Volvox (review)

A. Label the drawing of Volvox. Identify the , the individual cells, and daughter colonies.

1. How does this colony move? Volvox

2. To what phylum does Volvox belong?

3. How does Volvox obtain it’s nutrition?

4. What pigment is involved in photosynthesis?

5. What is the natural habitat of Volvox?

10.09 5A-11 Observation 8 – Marine Macro-algae There are three phyla of marine macro-algae: Green Algae, Brown Algae ( or kelp), and Red Algae A. Observe the fresh and/or preserved specimens on display. .B. Be able to distinguish between the phyla of algae on display. 1. Macro-algae are key producers in which aquatic ?

2. What pigment is responsible for the green pigment in algae and plants?

Phylum Green Algae 3. List an example of a green macro-alga (on display).

4. What is the cell wall made of?

Phylum Red Algae Specialization 5. List two examples of red algae on display. a. b. 6. What is the advantage of the red pigment found in red algae?

7. What substance deposited in the cell wall makes coralline red algae hard?

Phylum Brown Algae Specialization 8. List two examples of brown algae on display. a. b. 9. List the two pigments found in brown algae. a. b.

10. What is the cell wall made of?

10.09 5A-12 Macro-Algae (Protist Kingdom) and Land Plants ( Kingdom) 11. Which algae are the closest relatives of land plants? Why ?

12. Draw and label a 13. How does this brown alga with a blade, compare to that of a typical bladder, stipe, and holdfast. ?

14. Similar structures found in genetically unrelated organisms are often attributed to their to similar environments or similar way of (). When two different lineages face similar environments, constraints, or problems, may act on both lineages in the same way. This process can cause both lineages to evolve similar traits or structures. This is called "convergent ." What specific environmental factors and/or “way of life” may have selected for the similar body plans of kelp in the sea and plants on land?

10.09 5A-13 Phylum Example(s) or Means of Pigments Habitat Special Characteristics Locomotion (if any) Cilates

Amoeboids

Euglenoids

.Dinoflagellates

Diatoms

Green Algae

Red Algae

Brown Algae

10.09 5A-14