Observation 3

There are markedly less Rotifer Philodinas this week; most are still swimming around, and there are more Rotifers that are much smaller in size, indicating that they are perhaps reproducing. There is also growth, either protist or algae, in small clumps on the inside walls of the Micro Aquarium.

Dr. McFarland identified many different types of microorganisms in the sample that I had not noticed before.

First, there are three types of cyanobacteria in the sample: Cyanobacteria Nostoc, Cyanobacteria Calothrix, and an unknown cyanobacteria. According to the Berkeley website on cyanobacteria, they are aquatic and photosynthetic bacteria, responsible for the generation of oxygen in the atmosphere billions of years ago, and are probably responsible for giving early plant forms the chloroplasts needed for photosynthesis. The website for more information is http://www.ucmp.berkeley.edu/bacteria/cyanointro.html.

Cyanobacteria Nostoc: a freshwater bacteria; are single-celled but can form colonies; perform photosynthesis without chloroplasts; do not have a nucleus or internal membrane system.*

Cyanobacteria Calothrix

unknown cyanobacteria

There was also a large array of protist life in the Mircro Aquarium. Protists are a kingdom of life that are eukaryotic and cannot be categorized into any of the other kingdoms (fungi, animals, plants). Three types of protists were identified in the water sample: Amoeba Protist, Protist Difflugia, and Protist Vorticella.

Amoeba Protist: single-celled protist; movement caused by extension of pseudopodia ("false feet"); it surrounds and engulfs its food; has a nucleus. **

Protist Difflugia: single-celled protist; has a protective shell that surrounds the cell.**

Protist Vorticella: has cellular specialization (stalk and inverted bell shapes); can swim freely or anchor themselves to small particles; reproduce by fission (budding); have cilia and a nucleus. ***

Dr. McFarland also located another type of rotifer: the Rotifer Lecane. In this picture also are some small spore-like dots that are attached to each other, and permeated most of the Micro Aquarium. They resemble spores from algae meiosis, and I believe are strong signs of the reproduction cycles of the algae in the aquarium.

Rotifer Lecane and spores

*http://www.microscopyu.com/galleries/confocal/nostoc.html

**http://www1.fccj.org/dbyres/protista.htm

***http://www.microscope-microscope.org/applications/pond-critters/protozoans/ciliphora/vorticella.htm