Supergroup SAR – Lab Exercises

Please choose one live specimen or prepared slide to image. Take a picture under the microscope and submit via Canvas. Make sure that your picture is appropriately centered, cropped, and focused. Add a scale bar.


Exercise 1: Examine oomycete (water mold) Saprolegnia.  

Make a fresh mount and examine Saprolegnia.  Saprolegnia consists of coenocytic (without cells) filaments that grow on dead and decomposing organic matter.  Saprolegnia is oogamous, forming sperm in an antheridium and egg cells in an oogonium. Biflagellate zoospores are formed in a zoosporangium.  Draw a portion of an individual.  Draw and label visible features.

Exercise 2.1: Examine diatom Navicula.  

Make a fresh mount of the marine diatom Navicula.  Is Navicula centric or pennate?

Draw an individual showing markings on the frustules.

Exercise 2.2: Examine Mixed Diatoms. 

Examine prepared slides or make a fresh mount from the vial of field collected diatoms.  Are the observed diatoms centric or pennate?  Are any of the diatoms motile?  If so, describe their movement.  Draw two different types of diatoms.

Exercise 3: Examine chrysophyte (golden algae) Synura.

Make a fresh mount of the golden alga Synura.  Synura is a colony of flagellated cells covered with siliceous scales. Draw a cell of Synura.  Draw a small colony.

Exercise 4.1: Examine phaeophyte (brown algae) Ectocarpus.  

Make a fresh mount of Ectocarpus.  Observe and draw a small portion of this filamentous brown alga.  Are reproductive structures present?  If so, draw one.

Exercise 4.2: Examine the available specimens of kelp.  

Examine the available herbarium sheets of west coast kelps.  Observe stipes, blades, and pneumatocysts.  Draw a specimen of your choice.


Exercise 5.1: Examine ciliate Paramecium multimicronucleatum

Make a wet mount of live Paramecium. Sketch a cell. Do you see any conjugation taking place?

Exercise 5.2: Examine ciliate Bursaria truncatella

This is one of the largest ciliates. It preys on Paramecium. Make a wet mount that mixes one drop of live Bursaria culture with one drop of Paramecium culture. Sketch a Bursaria. Observe the wet mount. Do you see predation?

Exercise 5.3: Examine ciliate Stentor coeruleus.

 Stentor is different in morphology than the other ciliates you have examined. It looks like a large trumpet and attaches itself to vegetation or other substrates by a holdfast. They have a ring of cilia at the anterior end, which they use to direct food into their oral apparatus. The macronucleus of Stentor coeruleus may appear to be blue. Sketch a cell. Can you see the blue pigment? What is the Stentor doing?

Exercise 6: Examine live dinoflagellates

Make a wet mount of the live dinoflagellate culture. There are three species. Can you distinguish them based on morphology? Examine at least at 63x magnification. You may wish to use Protoslo if they are moving too quickly. Draw a dinoflagellate.

Exercise 7: Examine apicomplexans

Examine a prepared slide of Plasmodium sp. The four species of Plasmodium that cause malaria are the most deadly eukaryote to humans worldwide. These slides are blood smears. The infected cells will be larger, with the Plasmodium visible as dark staining inside the cell. Draw an infected blood cell.


Exercise 8: Examine Foraminifera.  

Examine a prepared slide of foraminifera tests.  Draw a foram.

Exercise 9:  Examine Radiolaria.  

Examine a prepared slide of radiolarian skeletons.  Draw a radiolarian. Please also examine this slide under darkfield (available on two of the compound microscopes).