What do aquarium snails eat?

 Goal:

• With the help of written directions or in a presentation, the student will prepare microscope slides of specimens that they have collected in the sample.
• Equipped with a microscope, the student will draw photosynthesizing and non-photosynthesizing protists.
• The student will observe the eating habits of the snails that inhabit the aquarium.

Materials:

• Aquarium in use
• snail.
• microscopic slides
• cover sheet
• microscopic
• toothpick

Process: 

1. Observe the snail activity in your classroom aquarium and record your observations.

2. Use a toothpick to take a sample of the green film from glass and other surfaces.  Place some on a slide sheet.

3, Mix the scraped material with a drop of water.  Carefully cover each sheet with a cover sheet.

4. Look for cells in the sheets and write down their appearance.  It is portable each sample contains several different types of cells.

5. It attempts to differentiate photosynthesizing protists from cyanobacteria.  Protists will have chloroplasts that will look like dark green areas inside the cells.  Cyanobacteria usually have a uniform color because they do not have organized chloroplasts; They are also smaller than protists.

Biggs, Kapicjka y Lundgren (2002) Biología Dinámica de la Vida, p. 523 

Analysis: 

1. What evidence did you find that the snails were consuming photosynthesizing organisms in the tank?

2, What do the cells you collected look like? Did they contain chloroplasts?

3. What conclusion did you get about the photosynthesizing organisms that are eaten by the snails in your aquarium?