User:Claudia J. Woloshchuk/Notebook/Biology 210 at AU

Thursday, January 29, 2015: Lab 3 Microbiology and Identifying Bacteria with DNA Sequences

Purpose: The purpose of this lab was to understand the characteristics of bacteria, to observe resistance and to understand how DNA sequences are used to identify species.

Materials and Methods: In order to understand bacteria and observe resistance bacteria from the Hay Infusions were placed on 8 serial dilutions. Four of the serial dilutions had just an agar nutrient and the other four had agar nutrient and tetracycline. Therefore if any bacteria grew on the agar plates with tetracycline, it would be understood that that bacteria was antibiotic resistant. Bacteria cell morphology was the observed using the bacteria from the agar plates, including the plates with tetracycline if bacteria had grown. This was done by creating four wet mounts using two bacterial samples from the agar plates without tetracycline and two samples from the agar plates with tetracycline. The bacteria was observed under a microscope at 10x and 40x. Then oil was used to observe the slides at 100x. Four gram statins were then made using bacteria samples from the same colonies within the agar plates. Lastly, PCR set up was completed for 16s sequencing.

Data and Observation:

Conclusion:

1.27.15 Good first entry. For future entries try to organize lab book into: Purpose, Materials & methods, data & observations and conclusion future directions. You also need to address the red text from the manual. SK

Thursday, January 22, 2015: Lab 2 Hay Infusion Culture

The Hay Infusion Culture, filled with soil and ground vegetation from the transect, smelled rotten (similar to a dirty fish tank). At the top of the jar there is floating berries, a wood chip and a layer of what looks like slime. This layer could be algae. At the bottom of the jar there is soil, moss, and some pieces of wood. In the middle of the jar there is dirty water with small bits of brown debris floating in it.

We took two samples for microscopic observation. One came from the very top layer of the jar with the layer of algae and the other came from near the moss at the bottom of the jar. The organisms may differ based on the location that we pulled samples form due to the fact that some organisms may prefer an area with more light and algae and others may prefer an area with more soil and plant matter.

From the wet mount made from the sample taken from the bottom of the jar we observed a Colpidium. This organism was motile, is a protozoa, non-photosynthesizing and consumes nutrients. It measured to be 26 μM. We found many of these organisms, around 20, on the slide that was made from the sample taken from the top of the jar as well.

Image taken from microscope:

From the wet mount made from the sample taken from the top of the jar we observed Gonium. This protozoa contained about 16 cells and was 20μM. Gonium are motile and are non photosynthesizing.

The Gonium that we found meets all the needs of life because it is alive. It is a live due to the fact that it acquires and uses energy, is made up of one or more cells (ours was made of 16 cells), it processes information, is capable of oogamous replication, and it is a product of evolution because it is part of the volvocine line.

If the Hay culture grew for another two months I predict that different organisms would develop and the organisms that were found already would grow, multiply and some would die.

One selective pressure that would affect the community of our samples would be the amount of sunlight let into the Infusion Jar, which would effect the photosynthesis of some organisms in the culture. Another selective pressure would be the variety of organisms living in the culture. A community needs a variety of organisms to go on and if organisms die off or were never there, this may be detrimental to the community.

-C.W.

Thursday, January 15, 2015: Lab 1 AU Transect

My lab group, Group 2, was assigned a 20 by 20 meter transect on American University's campus. The transect is located in between two sidewalks and a dorm building. It is part of a garden with benches, grass, many plants and trees.

Biotic components: trees, moss, bushes, shrubs, grass, berries Abiotic components: stepping stones, arboretum signs, shade from buildings, benches, pebbles, soil, the little bit of snow

Aerial view of transect:

Pictures taken of transect:

-C.W.

Thursday, January 15, 2015: Observing Evolution

Organism	Size	Reproduction
chlamy	10	iso
gonium	50	oo
volvox	214	oo

-C.W.