horizontal rule

Objectives

Students should be able to:

  1. Appreciation of biological diversity amongst the protists.
  2. Compare and contrast various sub-groups of protists, in terms of cellular structures, locomotory structures, and nutrition.
  3. Appreciate the complex taxonomy and divisions of the kingdom Protista
  4. Recognize and distinguish various representatives of algae (e.g., Diatoms, Chlamydomonas, Spirogyra, Volvox, Laminaria), protozoa  (e.g., Trypanosoma, Paramecium), and slime molds (e.g., Physarum)
  5. Understand the life history, ecology, habitats, and protective adaptations of selected protists.
  6. Review the economic importance of the group Protista.

horizontal rule

Introduction

Unlike bacteria which are prokaryotic, protists are eukaryotic, i.e., are characterized by membrane-bounded organelles. Taxonomically, the group constitutes the Kingdom Protista. It is very complex and diverse in respect to cellular structure, nutrition and many other biological characteristics. The concept of one kingdom for such a diverse group is being challenged, for a number of taxonomists are arguing in favor of splitting up the group into six or more kingdoms to reflect obvious evolutionary differences. Cell structural variations amongst members of the group include unicellular, filamentous, colonial, and multicellular forms. The multicellular members are undifferentiated. The specialized protection for either the gametes or zygotes, as seen in plants, is generally lacking. 

Members include protozoa, algae, and slime molds. Each of these three subgroups is further divided into several hierarchical groups. For example, the unicellular, heterotrophic protozoa, are divided into pseudopods, flagellates, and ciliates on account of their locomotory structures. Modes of nutrition include heterotrophism (by absorption, ingestion, and parasitism), and autotrophism (by photosynthesis). Asexual reproduction is usual mode of propagation but sexual reproduction is also common.

horizontal rule

Pre-lab Activities

horizontal rule

Pre-Lab Activity #1  - Protist Taxonomy

Using information from your text, the Learning Resource Center (LRC), or the World Wide Web, make a list of:   

The major taxonomic groups (Phyla, singular noun, Phylum) of the Kingdom Protista. Indicate which members are photoautotrophs or heterotrophic (by ingestion or parasitism). Use the chart provided in Question #2 in the Pre-Lab Questions.

horizontal rule

Pre-Lab Activity #2 - Economic Uses of the Protists

Using information from your text, the Learning Resource Center (LRC), or the World Wide Web, find 5 uses of economic importance for the members of the Protista. Attach this to your Pre-Lab Questions.

horizontal rule

Pre-Lab Activity #3 - Protist Images

Using any resources available to you find and print out imagery of the following:

bullet

Ameoba sp.

bullet

Paramecium sp.

bullet

Euglena sp.

bullet

Volvox sp.

bullet

Spirogyra sp.

bullet

Fucus sp.

bullet

Plasmodium vivax

bullet

Trypanosoma gambiense

horizontal rule

Pre-Lab Activity #4 - Data Collection Sheet

Download and print out the Data Collection Sheet for Protists

horizontal rule

Pre-Lab Questions (html version)        Pre-Lab Questions (Word version)

horizontal rule

The Laboratory Activities and Data Collection

horizontal rule

Lab Activity #1 - Mixed Protozoa

Materials:

bullet

Microscope

bullet

Mixed Protozoa Slide

bullet

Data Collection Sheet

Procedures:

  1. Examine the prepared slide labeled mixed protozoa under the microscope.
  2. Observe the slide first under the scanning objective and then under low power and high power objectives.
  3. Sketch the various species (cells) seen. Use your text to help you recognize and name the organisms and label the cellular structures.
  4. Record your results on the Data Collection Sheet.

horizontal rule

Lab Activity #2 - Observation and Comparison of Additional Protist Slides

Materials:

bullet

Protist slides labeled A, B, C, and D *

bullet

Microscope

Procedures:

  1. Examine the additional slides labeled A, B, C, D. Follow the same as Lab Activity #1. Note any differences between the organisms seen on slides A, B, C, and D and the ones identified on the mixed protozoa slide.

  2. Record your results on the Data Collection Sheet.

Note: *A, B, C, and D refer to specimens of rhizopod (an Amoeba), foraminiferan (a Foram), ciliophora  (a Ciliate), and Zoomastogophora (a Flagellate).

horizontal rule

Lab Activity #3 - Wet Mount Slide of a Representative Green Algae

Materials:

bullet

Slide

bullet

Cover slip

bullet

Dropper

bullet

Specimen E *

Procedures:

  1. Prepare a wet mount (temporary slide) of specimen E *. Examine the preparation under the microscope.

  2. Sketch your observation on the Data Collection Sheet as seen under high power magnification.

  3. Using your book as a guide, label only those structures seen in specimen E.

Note: * Specimen E = Spirogyra culture (or equivalent)

horizontal rule

Lab Activity #4 - Examination of Representatives of the Brown Algae

Materials:

bullet

Specimen F

bullet

Specimen G

Procedures:

  1. Carefully examine preserved specimens F, and G. Compare and contrast these specimens with terrestrial plants in terms of   Cellular/Tissue differentiation and specialization (i.e. presence of  vascular tissue) and types and color of pigments
  2. Write your answers on the Data Collection Sheet (Lab Activity #4)

* Specimens F and G are preserved Fucus and Sargassum

horizontal rule

Lab Activity #5 - Examination of Additional Members of the Kingdom Protista

Materials:

bullet

Specimen H *

bullet

Specimen I  *

bullet

Specimen J  *

Procedures:

  1. Examine specimens H, I, and J.  List or sketch any two features of biological interest with respect to each specimen. Features of biological interest may include flagellum, pseudopodia, contractile vacuole, etc.
  2. Write your answers on the Data Collection Sheet (Lab Activity #5)

* Specimens H, I, and J are prepared slides of Trypanosoma, Plasmodium, and Plasmodial Slime molds, respectively.

horizontal rule

Post-lab Activity and Data Analysis

horizontal rule

Results and Analysis

bullet

Return all materials to their designated areas

bullet

Answer all questions and provide all information requested on the Data Collection Sheet.

bullet

Answer the Post-Lab Questions.

horizontal rule

Post-Lab Questions (html version)        Post-Lab Questions (Word version)

horizontal rule