User:Sydney Marshall/Notebook/Biology 210 at AU
February, 9, 2014
The title of this lab is Identifying Algae and Protists from a Hay Infusion Culture using a Dichotomous Key and Preparing and Plating Serial Dilutions. The purpose of this lab was to understand the characteristics of Algae and Protists and utilize a dichotomous key to identify the species of such organisms. This procedure helped in determining the organisms observed from different niches in our hay infusion culture. The main hypothesis for this experiment is as follows: *If our transect consisted of a large variety of botanical the hay infusion culture is going to have a large variety of organisms.
Procedure I: Using a Dichotomous Key to Identify Organisms in Hay Culture Observations
- Carefully, bring the jar to your workstation and note its appearance and smell.
- Take 1-drop samples from two major niches in the jar (middle and bottom) using a transfer pipette and note specific locations of the samples.
- Observe the organisms on a microscope and sketch detailed pictures of what is seen in the slides while noting its size in micrometers.
- Characterize the different organism by determine the mobility, photosynthesizing ability, and similarities with the dichotomous key.
Procedure II: Using a Hay Infusion Culture to Prepare and Plate Serial Dilutions
- Take 4 tubes of 10mL sterile broth and label them 2, 4, 6, and 8.
- Obtain four nutiret agar plates and four agar plus tetracycline plates and label them 10-3, 10-5, 10-7, and 10-9.
- Using a micropipeter, obtain 100 microliters of hay infusion culture and place it in the tube 2 to make a 10^-2 dilution. Mix well.
- Obtain 100 microliters of the mix in tube 2, and place it in tube 4 to make a 10^-4 dilution. Mix well.
- Repeat for tubes 6 and 8 to make 10^-6 and 10^-8 dilutions, respectively.
- Take 100 microliters of mixed liquid in the 10^-2 tube, and carefully spread it on the surface of the nutrient agar plate labeled 10^-3.
- Repeat step 5 using tube 4 on the 10^-5 plate, tube 6 on the 10^-7 plate, and tube 8 on the 10^-9 plates.
- Incubate for a week at room temperature.
Procedure I: Using a Dichotomous Key to Identify Organisms in Hay Culture Observations
Description of Hay Infusion Culture
- Smell: strong and musty
- Appearance: dirty, murky, moldy, has a layer of film on the surface of water
Figure 1: Two organisms found in middle and bottom of hay infusion culture, respectively.
Table 1: Descriptions of the two organisms found in hay infusion culture
| ' | (left) | (right) |
| Type of organism | Bacteria | Algae |
| Shape | Bacilli | Oval |
| Color | Black | Green |
| Size | 2 micrometers | 2 micrometers |
| Photosynthesic capabilities? | No | Yes |
Figure 2: Nutrient Agar Plate Set-Up
In this lab, we were supposed to determine whether the diversity of botanical life corresponded to the amount to life in our hay infusion culture. I determined that since I was only able to identify two organism that my hypothesis was proved false. I interestingly found bacteria in addition to algae and thought it met all the needs of life because it is unicellular, acquires and uses energy by decomposition of organisms, processes and transfers genetic material by means of conjugation, capable of replication through colonies that will be observed next week, and is a product of evolution because it can evolve by being resistant to certain antibiotic strains.
If the hay infusion culture were to be observed for another few months, I would predict that more organisms could be easily identified. I managed to find bacteria as one of my organisms which is usually very tiny, and given time, more could have been found in the culture. Also, more mold could grow on the sides of the culture. Some selective pressures that affected the compositions of my samples were that my transect was in a very shady area surrounded by large trees. Therefore, there is a lot of moisture held in this area giving rise to diverse populations of algae. Even though I was only able to find one algae sample, it is possible that there were more types in other niches in my culture.
January 30, 2014
The title of this lab is Observing the Evolutionary Specializations of Cells in the Volvocine Line and Determining the Characteristics of a Niche on Campus. The purpose of this lab was to determine the evolutionary changes of cells within the Volvocine line, specifically from the Chlamydomonas, Gonium, and Volvox. The second procedure was to take a sample of our transect #2 in order to make a hay infusion culture for studying bacteria in the following week. The two hypotheses for each procedure this experiment are as follows:
- If the origin of the Volvocine line is Chlamydomonas, then the evolutionary progress of the following cells should exhibit more complexity.
- If the transect is in an area not frequently disturbed by human presence, then there will be a wide range of organisms to observe.
Procedure I: Observing the Evolutionary Changes in Cells within the Volvocine Line
- Prepare slides of Chlamydomonas, Gonium, and Volvox using a light microscope.
- Analyze the evolutionary specializations such as number of cells, colony size, relations of structure to function, and reproductive specializations.
Procedure II: Observing Characteristics of a Transect on Campus
- Go to a 20x20 foot transect near campus and describe general characteristics such as location and land profile.
- Determine the biotic and abiotic components of of the transect.
- Take a soil sample from the transect that is an accurate representation of the transect as a whole.
- Create a hay infusion culture using the retrieved soil sample.
- Put sample in a jar with 500ml of deerpark water.
- Add .1 grams of dried milk in the jar and label it for next week's use.
Procedure I: Observing the Evolutionary Changes in Cells within the Volvocine Line
Table 1: Evolutionary Specialization of Members of the Volvocine
| Characteristic | ' | Chlamydomonas | Gonium | Volvox |
| Number of Cells | 13 | 14 | 10000+ | |
| Colony Size | 1μm | 4μm | 5μm | |
| Describe any functional specialization of cells | motility (flagella) | form colonies with similar cells | motile flagellate cells, form spherical colonies made of glycoproteins | |
| Describe any reproductive specialization (isogamy vs oogamy) | isogamy of motile cells fusing together to make a gamete | isogamy - cells can function as gametes and fuse together to make a zygote | oogamy - female is nonmotile and males are motile |
Figure 1: Sketches of Three Organisms within the Volvocine Line
Procedure II: Observing Characteristics of a Transect on Campus
General Characteristics:
- Located Behind Cassell Hall and in front of Wesley Theological Seminary
- Shaded under flowering and non-flowering organisms
- Abiotic components:
- Holly
- Ivy
- American Sycamore
- Pine Tree
- Biotic components:
- Aluminum Foil
- Soil
Relating back to the purpose of the lab, our group was to determine whether there was significant evoltionionary change in the original Chlamydomonas algae based on its predecessors, the Gonium and Volvox. According to Table 1, the number in cells in each slide increased, as the Chlamydomonas algae evolved over time. Also, the colony size increased from 1um to 5um. The most significant differences were the structures, starting as individual motile cells to spherical motile colonies made from glycoproteins. In addition, the reproductive specialization changed from isogamy, the fusion of cells to make gametes to oogamy, with the female gamete being nonmotile and the male sperm motile. Therefore, the original hypothesis is confirmed by this increase in complex progression over time. A sample sketch of what was seen in the slide can be found in Figure 1.
Based on the transect observations, it was to be determined whether or not a lack of human presence within the transect indicated a large amount of organisms. Our group found that there were a variety of biotic factors found such as Ivy, holly, pine, and sycamore. Only one unique abiotic component, other than soil, was found, which was aluminum foil, and I assumed that because of this, this transect was not commonly disturbed by human company. Although this information is not enough to determine whether the transect is a place containing a large variety of organisms, I conclude that my data does not support my hypothesis because visually, our group could not find organisms other than botanical organisms . However, I believe that in next week’s lab, I will be able to look at a microscopic view of the organisms that the transect can contain, possibly supporting or refuting my hypothesis. Because of this lack of information in the experiment, I would maintain my hypothesis for the next experiment to determine whether or not there is a large variety of bacteria and protists, In addition, it was hard to see the transect in the dark, therefore had there been an adequate amount of light, there would have been other organisms that our group could have observed.
Excellent Lab 1 entry. Very thorough, well explained and organized. SK
January 22, 2014
Test.
