User:Sierra L. Stratton/Notebook/Biology 210 at AU

January 28th, 2015 Identifying Algae and Protists in Hay Infusion and Preparing and Plating Serial Dilutions

Purpose: In this lab we examined the protists and algae, under a microscope, living in our Hay Infusion from transect three. We took samples from two different niches in our Hay Infusion. We then identified the protists and algae using a dichotomous key, which consists of a set of questions concerning the physicality of the protist or algae. Because the samples were form two different niches I expected some variability in the protists found in the samples but I also expect some overlap in protists found because they are still from the same Hay Infusion. We also prepared and plated serial dilutions of our Hay Infusion culture to study next lab.

Materials and Methods: • Hay Infusion was very carefully, as to not disturb the contents, brought over to table

• Samples were taken from two different niches in the culture, the 1st was from the top of culture, the 2nd was taken from the bottom near a berry

• A wet mount was made from each of the samples

• Wet mounts were observed under a microscope, first at 4x, next 10x, then at 40x

• All organisms were identified using a dichotomous key

• Next we prepared and plated serial dilutions of our Hay Infusion culture

• The lid was placed on our Hay Infusion culture and the jar was shaken so the contents would mix

• Four tubes with 10mL of sterile broth were labeled 10-2, 10-4, 10-6, and 10-8

• Four nutrient agar plates and four nutrient agar plates with tetracycline were labeled 10-2, 10-4, 10-6, and 10-8 on the agar side on the plate, but the plates with tetracycline were also labeled with “tet”

• 100 microliters of our Hay Infusion culture was added to the tube labeled 10-2 then the tube was swirled

• 100 microliters from tube 10-2 was added to tube 10-4, and the tube was swirled

• This entire process was repeated two more times to create the 10-6 and 10-8 dilutions

• A spreader was disinfected, by being put into an ethanol bath, then put into a flame and was allowed to cool, before being used to spread each dilution onto a plate

• 100 microliters were pipetted onto both the agar nutrient plate and the agar nutrient plate with tetracycline

• Then the dilutions were spread onto their respective plates

• This process was repeated three more times for each dilution

• Plates were then placed on a rack to incubate for a week

Data and Observations: The Hay Infusion culture appeared to have several clumps of soil floating at the top, but there wasn't plant life growing in it. The culture smelled like stagnant water and mold, it was rather unpleasant. There were various different kinds of protists and algae found in the samples taken from our Hay Infusion culture. In sample 1, taken from layer, bursaria truncatella, gonium, and pelomyxa were found. In sample 2, taken around a berry at the bottom, colpidium, chlamydomonas, and blepharisma were found.

Table 1: Organisms found in Hay Infusion Culture

Sample	Organism	Size (micrometers)	Motile?	Protist or Algae
1	Bursaria Truncatella	90	yes	Protist
1	Gonium	100	no	Algae
1	Pelomyxa	300	yes	Protist
2	Colpidium	300	yes	Protist
2	Chlamydomonas	30	yes	Algae
2	Blepharisma	400	yes	Protist

Photo One:

Photo Two:

Conclusions and Future Directions: It was surprising that there were several different species found living in the different niches, even though they came from the same Hay Infusion culture. But it is understandable because some of the organisms were found near plant life, the berry. The organisms near plant life may differ because they could use the plant life as a food source or it needs the same conditions as plant life to survive. One organism we found that does this is the chlamydomonas. Chlamydomonas is a unicellular green algae found in stagnant water, damp soil, or even snow. This organism meets the requirements for life because it is a membrane bound cell, obtains it's energy through photosynthesis, passes genetic information on through both asexual and sexual reproduction, and it is a product of evolution. If my Hay Infusion were to "grow" for another two months I would expect to see more diversity of organisms present due to more things decaying and then being available as a food source.

SLS

January 26th, 2015 Biological Life at AU

Purpose:In this lab we began our study of a, roughly, 20 by 20 meter transect of land here at American University. From that transect we will take a soil and plant life sample, create a Hay infusion from the sample, and then discover what type of protists are found in our transect. By collecting samples from our transect, and observing it over several weeks we are able to study the community living in the transect. Through our study of the community in our transect we can discover the different niches, or the precise environmental necessities in their ecosystems, that the organisms have. All of this observing of organisms and our transect will aid in our study of biodiversity.

Materials and Methods:

• My group’s transect is number three, or the tall bushes transect.

• Group members observed the 20 by 20 area

• Drew an aerial view of the transect and took pictures of the area

• Collect soil and ground vegetation sample in a 50mL sterile tube

• Taking the sample back to lab we began to make our Hay Infusion

• Measure out 10-12 grams of the soil/vegetation sample

• Add the sample to a labeled plastic jar containing 500mL of water

• Measure out 0.1 grams of dried milk

• Add the dried milk to the soil and water mixture

• Put the lid on the jar and mix the contents of the jar together for about 10 seconds

• Take the lid off the jar and leave it in the lab for the week

Data and Observations: Within our transect we observed many abiotic and biotic factors in it. In our transect some of the biotic factors we observed were the bushes, trees, squirrels, birds, and spiders. Some of the abiotic components were rocks, metal plaques, the soil, snow, and we even found a rat trap in our transect.

Images of Transect Three:

Conclusions and Observations: Due to the several biotic components in our transect there will likely be many protists in our hay infusion. It is unlikely that our transect will change drastically over the next few weeks. So the abiotic and biotic components in the transect should remain the same.

SLS

January 21st, 2015

This is my first post for Bio 210.

SLS