Finding Specimens for the Foldscope

Notes of Caution

While collecting specimens for this lab is a low-risk activity, you are responsible for using common sense and due caution. You should be able to collect and prepare interesting specimens without entering bodies of water or using

potentially dangerous tools such as blades or scissors. Collect only in a location and manner that you judge to be safe, and do not risk injury or misadventure for the sake of this lab.

Please DO:

 Please DO NOT:

 

Specimen Collection and Preparation Tips

We've chosen chloroplasts as the organelle of interest for this lab because they are relatively large and easily recognizable. If you can find your own specimens that clearly show chloroplasts, then that's great, but it's not strictly necessary. Flora or fauna, there's plenty to see with the foldscope, and the most important aspect about this part of the lab is that you get to experience the thrill of discovery!

Additional Equipment

We provide you with a foldscope, transfer pipette, and a pair of gloves. You should also gather together the following items:

Algae and Plants

Your best chance for getting a good view of chloroplasts is to find some filamentous green algae. At your collecting site (see Collecting Tips: Locations, below), look for rocks or muddy patches with a greenish cast or film on the surface. In lakes, you may also see obvious clumps of filamentous algae that are either clinging to rocks or floating freely in the water (but see Notes of Caution, above). On shore, look for a green film on the surface of rocks. If you or someone you know has a fish tank, you might find some algae there.

Plant leaves may also work, but they must be very thin - if a specimen is more than a few cell layers thick, then it will be too thick for the cells to be visible. Choose leaves from plants that that are naturally very small (rather than using fragments of larger leaves), and look near the exterior margins of the leaf or near the veins, where the leaf tissue is typically thinner. Mosses and other ground-hugging weedy plants are good candidates, as are fish tank ornamentals such as Elodea.

If you collect a small amount of mud from a damp or marshy area, you have a good chance of finding motile organisms, even if you don't find algae. You may even want to try collecting a spoonful of soil in a glass jar, adding some water, and leaving it to sit in a sunny location. After a few days, you may have some algae growing in the jar! (If you try this, choose soil from a damp or shaded area with lots of plants growing).

Other Specimens to Try (Optional)

None of these have chloroplasts, but they could be fun to try...

 

Collecting Tips: Locations

On / Near Campus

 

Further Afield

 

At the Site

Take a few photos of the site in general and the specific spot where you collect your specimen, safely collect the specimen, and make notes about the time, location, and weather conditions (see the assignment document attached to the dropbox for this lab).

If collecting wet or muddy specimens, nearly fill your specimen bottle with water from the site; then add your specimen. Or, bring some tap water with you, for algae that you may collect from relatively dry spots as well, such as the surface of rocks or soil. For sites on Halifax Harbour or the Northwest Arm, collect a small amount of water at the site. (This will be seawater; any specimens you collect that came from seawater should be stored in seawater, not fresh or tap water).

 

Finding Specimens

photo: filamentous algae, Lake Banook and Maynard Lake

 

Filamentous algae in various locations: attached to rocks in Lake Banook (1 and 3); on the surface of the mud near the shore of Maynard Lake (2 and 4 - look closely for the greenish film on the mud)

 

photos from around campus: moss, Ocean Pond, lichen

 

Locations around campus: (1) moss on a rock wall (2) Ocean Pond (3) lichen on a log behind Sheriff Hall (at the perimeter of the Dalhousie Outdoor Ecolab)

 

photos: walkway behind LSC

 

Locations around campus: the walkway behind the LSC, between the Psychology wing and Oceanoraphy (Sherriff Hall is in the distance, behind the trees; the Dalhousie Outdoor Ecolab is among the trees)

 

photos: beach at the end of South St.

 

Drift algae on the beach at the end of South Street, on the Northwest Arm.

 

photo: mud and algae in a spice jar

 

Grow your own algae in a jar - just add water!!

 

 

 


 


 


 

 


Image Credits
All photos on this page by Jennifer Van Dommelen.