User:Corey J Salas/Notebook/Biology 210 at AU

LAB #2: Identifying Algae and Protists

PURPOSE:
The general purpose of this lab was to practice using a dichotomous key to identify unknown algae and protists from our transect at American University as well as gaining a clearer understanding of the characteristics of algae and protists.

MATERIALS & METHODS:
This lab was divided into three main parts. The first was to assist students in using a dichotomous key, the second was to identify life at the microbiological level in the hay infusion culture prepared the previous week, and third to prepare and plate a serial dilution. In the first part of the lab, students were instructed to go around the room and observe different microscopic slides and use the dichotomous key to attempt to align their observations with the organism deduced using the key. Students were then instructed to prepare a wet mount of known organisms and observe them with the microscope at 4x and 10x magnifications.

In the second part of the lab, samples were taken from the hay infusion culture from the bottom, middle, and top sections arbitrarily assigned by the group members. Wet mounts were prepared and a determination of which protists or algae was undertaken using the dichotomous key.

The third part of the lab required students to create a serial dilution with a sample of the hay infusion culture and 10mLs of sterile broth. Four test tubes labeled 10^2, 10^4, 10^6, 10^8 with approximately 10mLs of sterile brother were used in the dilution. 100µl of the culture were added to the 10mLs of broth labeled 10^2, 10µl of the broth from the tube labeled 10^2 were then added to the tube labeled 10^-6, 10µl of the broth from the tube labeled 10^6 were then added to the tube labeled 10^8 which completed the serial dilution preparation. These dilutions were then plated on the nutrient rich agar plates in two sets, one set with +TET and one set without. See the serial dilution diagram below (Diagram1).

DATA & OBSERVATIONS:
The second portion of the lab yielded the most interesting results as organisms from the group hay infusion culture were being observed. All organisms observed appeared to be motile and were in both the algae and protazoan lineages. None of the organisms were more than 200µl in size and were not visible to the naked eye; therefore an assessment of their loitering near plant matter in the infusion culture is difficult . Observed in the samples placed on the wet mounts were the following:

Top: Chlamydomonas, Euplotes sp. Middle: Busaria Truncatella & Paramecium Aurelia Bottom: Paramecium Bursaria & Vorticella

Upon initial contact with the hay infusion culture, it is notable that the smell had changed from the initial preparation of the culture. There was a smell of putrefaction exuding from the jar as well as a white film that had formed in the top portion of the jar - the group assumes this is mold.

http://i35.photobucket.com/albums/d197/corey92/80c06dfa-4e75-43d9-96ca-57d17874c5fc_zpsea1eab04.jpg http://i35.photobucket.com/albums/d197/corey92/54c8cfee-37db-42bc-9a27-2017949fbc98_zps91100938.jpg

http://i35.photobucket.com/albums/d197/corey92/1d54e7bc-d75a-4d97-9a08-8281a6d174a3_zps3e6e7af0.jpg http://i35.photobucket.com/albums/d197/corey92/34c8d0aa-8417-4a12-9c91-9066bac5ee23_zps698186af.jpg

Figures 1-4: Hay infusion culture exterior and microscopic observations.

http://i35.photobucket.com/albums/d197/corey92/HayInfusionDilutionDiagram-01_zps7cc27795.png Figure5: Serial dilution of hay infusion cultures to agar plates.

CONCLUSIONS & FUTURE DIRECTIONS:
Due to the biological nature of our study this semester, it is important to relate what we observe back to what we know about our definition of life. Thinking about the organisms observed in the hay culture, chlamydomonas serve well to bridge the gap between how we define life and how we observe the characteristics of that definition. Chlamydomonas has cells, uses energy (photosynthesis), grow and can reproduce - these are all characteristics that define life as well as characteristics of chlamydomonas itself. Thinking forward about how this culture might grow in the future, depending on environmental conditions, the infusion culture might grow more organisms or could very well kill them off due to lack of resources, it really all depends.

• Corey J Salas 17:16, 28 January 2015 (EST):

1.27.15 Excellent first lab book entry. Well structured and organized. Nice photo. Transect is 20 ft by 20 ft there is a typo in the manual. SK

LAB #1: Biological Life at AU

PURPOSE
The general purpose of the lab observations were to observe biodiversity as it exists in the environment as well as providing a means for a sample in order to create a Hay Infusion Culture which would further allow students to observe biodiversity on a more microbiological level.

MATERIALS & METHODS
During the in class portion of the lab, the volvocine line was observed in order for students to view the evolution of a line as well as to reorient themselves with the use of the microscope.

The materials used in the latter half of the lab were a sterile 50mL conical tube in which a soil/ground vegetation sample was placed as well as a clip board, notebook paper, and pencil in order to take accurate and detailed notes. A cell phone with a camera was also recommended in order to take photographs of the area. Students were randomly assigned a transect and were instructed to then travel to and observe the area, take detailed notes, as well as take a soil sample which was representative of the entire transect. In addition to making notes about the topography and general characteristics of the area biotic and abiotic features of the area were also recorded.

A secondary part of the lab was to prepare a hay infusion culture from the approximately 10-12 grams of the soil/ground vegetation sample mixed with 500mL of deer park brand water and 0.1g of dried milk powder. The mixture was mechanically disrupted with a lid on the jar and allowed to sit for approximately one (1) week. The hay infusion culture will be used to observe, on a microbiological level, the biodiversity present in the assigned transect.

DATA & OBSERVATIONS
General Transect Characteristics: The transect observed is an approximately 20 ft by 20 ft plot marked with four popsicle sticks. The transect was labeled transect #3 and is not perfectly rectangular in shape, rather one might compare it to the shape of a trapezoid. The ground is relatively mound shaped with consistent elevation in the center of the transect gradually decreasing toward the outer regions of the plot with concrete sidewalks surrounding the edges of the transect. The highest point of the transect is approximately 2.5 feet at its highest point measuring from the level of the concrete sidewalk. The transect is located approximately 20-30 feet from the bender sports arena and is located at approximately 38 degrees N and 77 degrees W. It is located near other areas of the recreational park as well as a major roadway that runs through the American University campus. The area is primarily used as a park area for students, faculty, staff and visitors to American University to relax and perform recreational activities. There are small shrubs, taller trees, and rotting foliage present within the plot as well as a diversity of animals and humans that come through the area at various times.

Biotic Features: 1) Squirrel, 2) Human, 3) Leafy Green Plants 4) Trees, 5) Small bushes
Abiotic Features: 1) Metal light post, 2) plastic meter box, 3) ribbon 4) concrete side walk, 5) stones

http://i35.photobucket.com/albums/d197/corey92/IMG_8206_zps21726b40.jpg

CONCLUSIONS & FUTURE DIRECTIONS
Based on the observations of the transect and the sample collected and prepared in the hay infusion culture, it is advantageous to say that there is much biodiversity present in and around the American University campus. It is also important to note that the changing biotic and abiotic features of the transect will be of particular interest to observe as the semester progresses.
--Corey J Salas 22:54, 26 January 2015 (EST)

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Test. Wednesday, January 21, 2014. *Corey J Salas 15:02, 21 January 2015 (EST):