User:Austin Cohen/Notebook/Biology 210 at AU

Bio-Lab 210 Exercise 2: Identifying Algae and Protists 07/2/15

Introduction:

Although algae and protists are very small, with the invention of the microscope we are able to observe and characterize these different organisms. Sometimes identifying them is a difficult task as well because of there small size, so a Dichotomous Key can be used. This key puts the observer of these small protists through a series of observations to guide them in their identification of the algae and protist.These can include observations about the size, shape, color, and movement Identification of protists is important for many reasons such as understanding the evolution of the organisms as well as their function in the ecosystem.

Methods:

First the group practiced using the Dichotomous key using a known sample. To do this we made a wet mount of a known organism and observed it under a microscope start at 4x and increasing to 100x. After following the steps given by the Dichotomous key we were able to identify many different organisms our known experiment. Before putting samples from our niche created in the Hay infusion from the previous week under a microscope to identify organisms in it, we made observations about it. The group then split up the niche in the jar into two different areas to take sample from. We took two samples from the surface of the top of the jar and two samples from the bottom of the jar which all included some plant matter. After this the group made a wet mount of the 4 different places within the niche and observed them under the microscope while using the Dichotomous key to identify organisms. After performing this we prepared our plates and serial dilutions (see key in results section).

Results:

Our hay infusion jar had a very strong dry odor that smelled moldy. There also appeared to be life in the jar as the top and bottom of it contained a brown moldy substance. The protists appeared to cluster around plant matter. This could be due to their scavenging for nutrients and it is present near the plant matter versus away from it. The the two images below to the furthest left are photos of our jar used for the Hay Infusion. The picture to the right of those two photos is a drawing of what we saw in the microscope form the two samples. The next two to the right from that are the samples from the top and then the next three are samples from the bottom. We were able to identify Parenema (30 micrometers) and Gonium (80 micrometers) from the top sample as well as Stentor Coeruleus (2 micrometers), colpidium (50 micrometers), and Spirostomum (2 micrometers) from the bottom sample.

AustinCProtist1.JPG AustinCProtist2.JPG AustinCProtist3.JPG AustinCProtist4.JPG AustinCProtist5.JPG AustinCProtist6.JPG

Discussion:

The group was successful in identifying the organisms in our Hay infusion culture. The organisms we found meet all of the need of life by the way that they are all made up of cells, they use energy, they pass down information, replicate as well as evolve to the niche we put them in. Because they can evolve if the Hay Infusion culture grew for another two months we would observe a large change in the types of organisms in the jar. Assuming that the jar is not left in the sun, non-photosynthesizing organisms would be more abundant than those that photosynthesize. This is an impactful selective pressure that could occur. The amount of organisms in the jar would also increase due to reproduction as well.

Bio-Lab 210 Exercise 1: The Transect and the Volvocine Line 06/30/15

Introduction:

The Transect used was a green lawn on the American university campus and rich in vegeation. Analyzing transects is very important in order to study the ecology around the American University Campus. The transects contains both biotic components, which are the living components, and abiotic components, which are the nonliving components. Both of these components are necessary for ecological research.

Methods:

In a group of four students, the 20x20 foot dimensions of the transect marked with four popsicle sticks was located. The transect was in between Hurst Hall and the East Quad Building on the side next to the the street, Nebraska Avenue (Map in results section). General characteristics, an aerial map with North, East, South, and West labeled, as well as a list of the biotic and abiotic components of the transect were created. A ground sample of soil was taken for the hay infusion. The group was careful to only take soil and leave out extraneous vegetation. The soil was then brought back to the lab to proceed with the hay infusion. In the lab we weighed and mixed 10 grams of the soil with 500 mL of Deerpark water in a plastic jar. 0.1 grams of dried milk was then added to the jar and then mixed, after putting on the lid, for 10 seconds. The jar was then labeled and placed with the lid off in a safe place in the lab.

Results:

The general characteristics that were observed about the transect was that there were many leaves on the ground, as well as a lot of green vegetation, the grass was not maintained and therefore very tall. It contained statues, lampposts, and sprinklers as well. There did not appear to be very much human interaction with the land. The group also listed the biotic and abiotic components of the transect. This included the biotic components of insects, trees, flowers, and fungi. It also included the abiotic components of sunlight, water, heat, air, rocks, and soil. The biotic and abiotic factors were all spread about the transect, but most of the biotic components were on the ground surface or in the soil. Below shows an aerial map of the transect as well as a few images of it.

ACTransectMap.JPG ACTransectlab1.jpg ACTransectlab2.jpg ACTransectlab3.jpg ACTransectlab4.jpg

Discussion:

This experiment included both the general observations of the transect as well as the preparation to do more specific studies on the ecology of it. We were successful in gathering this general information as well as prepare the hay infusion to set up our further studies in the next lab. Information about the ecology of our transect will be useful in assisting us in our interactions with land around campus as well as making us more aware of the health of our campus environment.