User:Yasmine Yaiche/Notebook/Biology 210 at AU

Understanding Algae & Protists through a Dichotomous Key perspective – 01/25/2015

The Purpose: The purpose of the following Lab II is to familiarize ourselves with Unicellular Eukarya and to further identify the two large groups it entails: Algae and Protists. Furthermore, the purpose is to understand how to use a Dichotomous Key by obtaining an organism and focusing in on the organism under the microscope. In regards to a continuation from our lab I to this current lab, we are asked to observe our Hay Infusion Culture by gathering two inter-samples from the surface of our sample and from the interludes of our sample (i.e. the surface of the moss for my sample). The purpose for this is to just observe what we see under the microscope and use the Dichotomous Key to identify what seems to be living in our sample. It is believed that if we gather smaller samples from our Hay infusion culture then we will be able to clearly identify more organisms in our culture. It is predicted that there will be a plethora of organisms found in our culture (at least 4 different organisms confirmed through identification via the Dichotomous Key).

Materials & Methods: - Sample of Red Algae and Brown Algae to initially identify and understand what a protists or algae may look like under the microscope and how we can use this image to further identify the organisms scientific name through a Dichotomous Key - Dichotomous Key = given to us to understand the various organisms that could potentially be present in our sample.This key is typically a paper sheet and is listed below as a means of classifying these organisms. - Microscope = used to identify class examples of protists and algae as well as our own personal sample. Throughout lab it is KEY to begin at 4x and further proceed onto 10x and 40x. Some organisms are difficult to find under 10x and others under 40x - this is because of the likelihood that the organisms may be moving at a quick pace. In this case, using a special dilution drop will allow for accuracy in observation. - Hay Infusion Culture = which includes a mixture between our sample, deerpark water, and dried milk - Petri Dish plating of our sample in order to further confirm the existence of these organisms and the impact of its growth once placed in an incubator (this is to test what selective pressures would affect the community of our sample).

- How to perform the preparation/plating of Serial Dillutions: 1) Four tubes were provided in class (and should be provided by the professor). These tubes hold 10mL os sterile broth each with 10-2,10-4, 10-6, and 10-8. These tubes are labeled and a micropippetor (set at 100 mL) is used to administer the broth into the agar plates. The method of using the micropippetor is to increase accuracy in terms of how much of the broth makes it to the plate.

2) Eight plates are provided by the professor - exactly 4 nutrient agar and 4 nutrient agar plus tetracycline. Each of the four plates are labelled as 10-3, 10-5, 10-7, and 10-9. The reason these plates are labelled with a digit above that of the tubes may be due to slight error. Either way, the administration of the broth's into the plates are labeled in chronological order.

3) Therefore, the 10-2 broth is administered into the 10-3 broth, the 10-4 broth is administered into the 10-5 broth, and so-on.

• • To administer the broth onto the plate, one must obtain a inoculate "tube" that is sterilized once placed in a lit-fire or gas-exchange. This is to kill any unwanted bacteria from making it into the plate and affecting results. This inoculate sterilized tool is used to swirl the Hay Infusion Culture around the petri-dish to maximize growth accuracy. (KEY: ONCE YOU HAVE HEATED THE INOCULATION TOOL, DO NOT PLACE INTO THE BROTH-PLACED PLATE --> THIS WILL BURN THE BACTERIA AND THEREFORE KILL IT - WAIT A FEW SECONDS)

4) Repeat the procedure on each plate by placing the broth onto the petri-dish and then using the inoculation tool to spread it around the plate - the professor will be able to help, such that any questions arise.

5) The final step is to place the agar plates on a specified rack where incubation for exactly one week will take place (room temperature).

Data: When observing our sample under the microscope, we found that a majority of the sample embodied various organisms rather than one. This can create another assumption, rather prediction, that a plethora of places where biological life may be found (i.e. Marsh environment), contains an abundance of various protists or algae life. This is confirmed through observation under the microscope and collected data through identification via a Dichotomous Key. After identifying the organisms under the microscope, we found that sample 1 (surface water of our culture) displayed Paramecium Caudatum (280-300 micrometers in length), Colpidium (50-70 micrometers), Bursaria Truncatella. In Sample 2 (just beneath the moss sample found at the bottom of the culture) Vorticella, Paramecium Aurella, and Chlamydomonas, were three of the many organisms found in this section of the culture. The following Data entails several images gathered from lab that are important in displaying what was done and/or seen during the experiment. Two images display the Dichotomous Key as a basic visual on the various organisms that could be found (organisms in our sample are listed above - try finding these organisms in the Dichotomous key!). Additionally, one image displays a birds-eye view to show the surface of the water, whilst another shows where our moss sample was taken at the bottom of the jar, prior to observation under the microscope. One other picture is a caught image of a trial-and-error of the Paramecium Caudatum at 10x - exciting stuff!

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Conclusions & Future Directions: Conclusions cannot be deciphered at this time as the lab is still non-complete, however predictions of possible conclusions are mentioned above. Any possible future directions for this lab could be to gather more areas from our hay infusion culture by not only the surface or bottom of the culture but also from any plant-like material found in the sample.

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Earth’s Diversity through Natural Selection: A close look at Biological Life at AU – 01/24/2015

The Purpose: The purpose of the following Lab I is to observe three important organisms classified under the Volvocine Line and the significance of these organisms that happened to be found around various places around campus. The overall focus is geared towards the evolutionary specialization of members of the Volvocine Line, which entails the number of cells, colony size, specialization of the cells, mechanisms of motility, isogamous or oogamous characteristics, as well as understanding the view of these organisms under the microscope and its contribution to biological life through diversity in the ecosystem. Furthermore, a sample from the environment of AU will collected and tested/observed within the span of the next two labs. The Purpose of this is to understand biodiversity and its complexity in places as simple as moss or soil.

Collectively, classmates were operated into assigned groups and told to go to one specific place on campus that represents that of possible selective pressures that may contribute to increased complexity of the organism in its environment. In regards to my group, we were asked to go to a location of Marsh lands (mixture of moss, heavy soil, and collective rocks, wheat, and abiotic features in front of Kogod Business School). It is hypothesized that if a sample is collected into a tube half filled with soil from the marshy ground and half filled with botanic items such as damp moss, leaves, as well as particles from flowers found buried on the ground, that there will be a biodiversitized combination of protists, bacteria, and plant invertebrates in our sample. It is predicted that after using a Hay infused culture into our sample, that some sort of protest may grow within a span of the next week.

Materials & Methods: - Chlamydomonas, Gonium, and Volvox Samples 1) Chlamydomonas: Considered the origin of multicellular evolution in the Volvocine line. The specialization of cells are reproductive, rather vegetative. The mechanisms of motility consist of Flagella and they are isogamous. Information such as this is key to understand to better perform this lab and to better understand the organisms one is working with.

2) Gonium: Colony size is larger and mechanisms of motility are the flagella. These organisms are isogamous.

3) Volvox: These organisms require the use of a depression slide. Though they are vegetative and consist of reproductive cells, these organisms are oogamous. Use of a droplet to control movement of the fast-paced organisms are recommended to be able to better observe these organisms.

- Transect (Marsh Land in front of Kogod) a) Moss b) Dead leaves/grass c) Dead flowers and live petals from flowers d) Mixture of fertilizer and damp soil (previously rained) e) sticks - Microscope - Deerpark Water - 0.1 gm dried milk - Sterile 50 mL conical tube - Microscope

Methods regarding the Hay Infusion Culture Procedure:

1) Place about 10-12 grams of the ground/soil vegetation of your sample in the plastic jar provided by the lab instructor. 2) Add about 500 mL of deerpark water to increase chances of visualization of these organisms and any growth that may occur. 3) Add 0.1 grams of dried milk and close the jar. Mix the contents for about 10 seconds. 4) Remove the lid and place the jar in a safe place (labeled as well) so that the oxygen has a chance to reach any organisms in the jar.

• • By next lab: You will be able to observe and find a better "picture" of any organisms in your sample.

Data:

Map of Transect Location – The following are two images that exhibit the marsh environment through two parallel, yet different views. The picture exhibits the wheat, the marshy soil (zoomed out), the sticks, dead leaves, rocks, and all of the biotic/abiotic features.

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Figure 2:

List of 5 Biotic/Abiotic features in Transect Location: Biotic – Green Fallen Leaves, Grass, Moss, wheat Stocks, Bacteria or living organisms under the soil Abiotic – Sedimentary Rocks, snow, cement, sewage, metal sign planted into the transect location, trash with food items thrown around the transect (candy wrappers)

Conclusion: Conclusions cannot be made at this time as the experiment is still in the process of completion, however future directions should be to allow the student to observe organisms in a transect environment fairly different from the grounds of American University as similar chemicals are used around campus (i.e. fertilizer, plantations, etc.) that may kill or affect testing for any protists in the environment – this could ultimately alter biodiversity in the environment as well.

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01/21/2015

I would like to study Virology or Pathophysiology/Microbiology in the near future.

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