User:Kelly Donovan/Notebook/Biology 210 at AU

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3/22/14

Introduction: This lab serves to test a hypothesis dealing with embryology and the effects of something, in this case Alcohol, has on the development of zebra fish embryos. This expedient serves to provide insight into the effects of pregnant mothers drinking. Zebra fish embryos act very similar to human embryos and also can yield the same results. Because of this, they serve as great organisms to use in place of human embryos but still allow for incite into fetal alcohol syndrome.

Methods: Set up the control group and the test group in covered petri dishes. Then take 20 mls of Deerpark water and 20 healthy translucent embryos and place them in each dish. Use a dropper to transfer the eggs to the dishes with the appropriate water. Count the following: the number of dead eggs, the number of living embryos still in egg cases, the number of living zebra fish and the number of dead zebra fish On day 4: Remove 10 mls of water, any empty egg cases and dead embryos. then add 25 mls of test solution to test dishes and add 25 mls of water to the control dishes 3. On day 7: Add one drop of food to each dish. 4. Days 4 and 7 and 11: Observe larvae from each plate with the microscope. Place a couple drops of sample with some of the organisms in a depression slide and use the 4X objective. Record the following: degree of body and tail pigmentation (melanophores) - eyes and eye movement
- heart and possibly heart rate
- pectoral fin development

yolk sac size (absorbed by day 5-7)
- development of the swim bladder
- development of the mouth (protruding jaw)
- general movement; assign a quantitative score based on a rubric you develop.

5. On day 7: Fix at least three larvae from the control and at least three from the test dish. Use a dropper to get them into the tube. Add 1 drop of tricaine solution per ml of water. 6. On day 7 and day 11: Add 10 mls of water to the control and 10 mls water plus test additives to the test sample. 7. Final day with fixed samples:
- make observations listed in step #4
- measure the length of the tail
- measure the length of the entire larvae - measure diameter of the eyes Raw Data: On the first day of observation in the control 5 have hatched, all are alive. They are moving within their eggs, and are very sporadic. They are about 42 hours old and their yoke is still large but has shrunk. Their eyes are darker and moving to the sides of the fish. The tail has two black stripes on it and the side fin has started to form. Their heartbeat is 112 beats per min. The sizes range from 3-4mm. The alcohol treated embryos are all alive, 6 of them have hatched. The ones that are hatched sporadically dart from one end to the other. They are about 42 hours old and their yoke is still large but has shrunk and their eyes are darker and moving to the sides of the fish. Their tail also two black stripes and the side fin has started to form. They have a heart beat of 128 beats per min. Their size ranges from 2-4mm (Table 1). On the second day of observation the control embryos 14 have hatched 2 have not and 2 are dead. They still have decent amount of yoke, which makes sense because they are three days old. Their heart is beating 128 per minute. Their tails are long and very well shaped. The alcohol embryos have all hatched and zero are dead, however they still have decent amount of yoke because they are only three days old. The distance between the eyes is smaller and they have curved tails. Their heart beats 144 times per minute (Table 2). On the third day of observation the control zebra fish all have hatched and all are alive. They are moving and darting very quickly across the dish and there is still some yoke left. The development is normal and standard. The tails are longer, 3 black lines going across and their fins are ore developed and constantly moving, simmer blades are darker in color. Their heartbeat was 108 beets per minute. The treated zebra fish were all hatched and all were alive. They were very sporadic and fast/crazy and there is still some yoke left. They were smaller then the control and their tails are shorter and they were yellowish and they had smaller eyes. Their heart rate was 140 beets per minute (Table 3). On the fourth day of observation the control group have all hatched and 12 are alive. They are swimming around but not as fast or sporadically as wednesday. The fish are a little over a week old the yoke is almost entirely gone. The eyes are very dark and have grown. The tails have grown and now have three lines going down them. The fins are much more developed and are more efficient, the tail has grown. Their heartbeat was 105 beats per min. The alcohol treated fish have all hatched and 9 are alive. They are moving really slowly if at all. They are a little over a week old the yoke is almost entirely gone. The eyes are smaller than control and are not as dark. The tails are shorter and the lines on them are not as dark. The fins have developed normally and are larger, the tail has also grown. Their heartbeat was 132 beats per min (Table 4). On the fifth day of observation the control group have all hatched and 2 are alive. They are not moving unless poked. There is none to very little yoke remaining. The tails are larger and have continue to darken and the fins are more developed. Their heartbeat is about 72 per minute. The treated zebra fish have all hatched and all are dead. There was none to very little yoke remaining. The tails are shorter and they are curved rather than straight, they have smaller eyes and have a yellow color to them (Table 5). On the final day of observation all of the zebra fish were dead so the fish that were preserved on 2/26/14 were observed. The control group are much darker and they are larger than the alcohol. They have a tail length of 140 ocular spaces, a total length of 170 and an eye diameter of 14. The treated group are dark in color but it is not as dark as the control, they have a pupil. They have a tail length of130 ocular spaces, a total length of 160, and an eye diameter of 12 (Table 6).


Conclusion and future plans:
In conclusion all of the zebra fish died in both the alcohol dish and control dish, which is most likely due to the temperature of the laboratory. However, what was able to be observed was that the treated fish were smaller and pigmented yellow. They also did not have as dark of stripes in their tails or very large and dark eyes. In the future I would like to repeat this experiment with a better lab temperature and see if the results were different. I would also like to grow them for a longer period of time to see if the developmental impacts prove to serve to be detrimental as the fish get older.

Tables: https://docs.google.com/a/student.american.edu/spreadsheet/ccc?key=0Ar2AbpCFgv4xdHB0eGNKcmdCX1J3WlRWRENtX3dlR3c#gid=0 -KMD

3/13/14

Introduction This lab’s purpose is to gain a better understanding as to which bacterias are in the studied transect. It also helps to check our previous results to see if the correct bacteria was identified.

Procedures 1. Select a bacteria colony from each of the two plates that has the best characterization 2. Transfer the single colony of bacteria to 100 µl of water in a sterile tube 3. Incubate at 100°C for 10 min and centrifuge 4. Use 5 µl of the supernatant in the PCR reaction 5. Using an online database assess the DNA sequences of the bacteria

Discussion As Table 1 illustrates there were two different types of bacteria found in the DNA sequence for the Biology II Section 6 Transect 4 sequence 2. Both had very similar descriptions to bacterias originally described in the lab upon initial observation. The first bacteria is called Chryseobacterium and was originally described in lab as yellow in color, circular as well as some rods, glossy, uniform colonies, and gram negative. After identification, the bacteria was googled and officially described as yellow pigmented, Gram-negative, circular and rod shaped and can be found in soil, plants, foodstuffs and water sources. The second bacteria is called Flavobacterium and was originally described as irregular, light yellow cloudy, glossy, large and different in sizes, and gram negative. After it was identified by the online database the bacteria was googled and identified as 2-5 um long, 0.3-0.5 um wide, rounded ends that are motile by gliding, and yellow in color.

Conclusions and Future plans: As Table 1 indicates the two bacteria identified by the online database from the DNA sequence appear to be two of the same bacteria that were originally described in lab. This proves that the original descriptions were accurate. In the future I would repeat this experiment a few times to see if the results were the same. In addition, I would conduct this experiment at different times of the year to see if the experiment would yield different results and if they do, why that is.


Tables: https://docs.google.com/a/student.american.edu/spreadsheet/ccc?key=0Ar2AbpCFgv4xdDdKQW5qelV1dF9DTjR5S3ZjVWZRWnc#gid=0

Sources: http://microbewiki.kenyon.edu/index.php/Chryseobacterium_indologenes

http://microbewiki.kenyon.edu/index.php/Flavobacterium

-KMD


2/26/14

Introduction This lab is to try and help students understand the importance of invertebrates, and to learn how simple systems, including specialized cells and overall body plan, evolved into more complex systems. It looks at the different invertebrates that live in the transect and how different families of worms have specialized and evolved.

Procedures 1. Observe the acoelomate, Planaria with the dissecting scope 2. Observe the nematodes and a cross sectional slide of their pseudocoelomate structure 3. Observe the coelomate, Annelida 4. Break down the Berlese setup 5. Transfer the preservative solution to a Petri dish 6. Examine under a dissecting microscope 7. Identify the main groups of invertebrates

Discussion

The antagonistic worm moved very rigidly, it was not very fluid movement. This is because the muscles have to act through a skeleton because they do not have any natural muscle to both extend and contract their muscles (Britannica). The Pseudocoelomate worm moved in thrashes or jerks, due to the way their muscles contract to send them forward (Free thought). The Coelomate worm moves fluidly because its body structure allows for the muscles to move and contract independently from one another (Madsci). As table 1 indicates five organisms found in the transect were biting lice, which are 1-2.5mm in length, Fleas, which are 1.5-3.3mm in length, Flies, which are 3-4mm in length, and two different centipedes, which are 5.5-8.5mm in length. The biting lice have no wings but its body is not laterally compressed and it also has chewing mouth parts. The fleas have no wings and its body is laterally compressed with longer legs so that the organism can jump. The flies have a single pair of wings with a two part black body with large eyes and antennae. The first centipede is light brown with antennae, many legs and one central body cavity (Figure 2). The second centipede is dark brown and was living amongst the dirt in the transect. It has many legs, two antennae and one central body cavity (Figure 3). Most of the organisms in the transect are between the sizes of 2-3mm. The centipedes are the largest organisms and the fleas and flies are the smallest organisms. All of these organisms are common in leaf litter. Table 2 illustrates the classifications of the organisms looked at in lab, which included, and insect (Cicada), centipede, a crustacean (Crayfish), an archnid (Spider), and a millipede. The table indicates if the organisms have wings, if so how many, the number of antennae, the number of legs and the number of body parts or segments. As Table 3 indicates five vertebrates that would be common to the transect. They include, the common Virginia lizard, which is a part of the Reptilia classification, the Robin, which is a part of the Aves classification, the Crow, which is a part of the Aves classification, the common garter snake, which is a part of the Reptilia classification, and the common Virginia frog, which is a part of the Anphibia classification. They all have biotic and abiotic benefits that can be gained from the transect. Figure 5 shows the food web of the transect.

Conclusion

This lab showed how different organisms can have many different characteristics. In addition, it indicated which types of organisms benefit from the transect. In the future I would like to see if the types of invertebrates present in the transect changed throughout different times of the year. It would be interesting to see if the seasons had an effect on the number or types of organisms present. In addition, I would like to compare my group’s results with other groups’ in order to see if the different ecosystems played a part in the types of organisms.


Sources:

http://www.britannica.com/EBchecked/topic/25501/animal/31736/Acoelomates

http://www.freethought-forum.com/forum/showthread.php?t=18747&garpg=3

http://www.madsci.org/posts/archives/2005-03/1110764170.Zo.r.html

Tables: https://docs.google.com/a/student.american.edu/spreadsheet/ccc?key=0Ar2AbpCFgv4xdHBMS05HeV83SEhIS0hXeTN3UGx4VVE&usp=drive_web#gid=0

Photos: https://docs.google.com/a/student.american.edu/document/d/1G-kNx_36AWd7dC8YIjLzGmGqM_bfCnE8elTGMblg5LE/edit

-KMD


2/24/14

Introduction

The purpose of this weeks lab is to understand all of the many characteristics of plants as well as how diverse they can be. In addition this lab looks into the function and importance of fungi. It is widely accepted that land plants evolved from aquatic green algae. Over time, just like animals, the plants evolved based on the environment they were in and became different species with speciations. The types of plants found in an environment can indicate many things about the type of environment it is in addition to the other organisms that may reside there.

Procedures 1.  Bring three plastic bags to your transect 2.  Obtain a leaf litter sample from a site at your transect a. Find an area with soft soil and dead leaves or ground cover b. Dig only into the top layer of the soil and the plant matter above it c. Place about 500g of litter into one bag 3. Take representative samples from five plants 5.  Find any seeds, pine cones, flowers etc. from the plants 6. Bring them back to lab 7. Observe the moss, Mnium 8. Note the height of the plant 9. Examine the cross section slide of the lily stem 10. Find the xylem and phloem layers 11. Measure the height of the lily plant stem 12. Make a Berlese Funnel a. Pour 25 ml of the ethanol/water solution into the flask b. Cut and place a piece of the screening material into the bottom of the funnel c. Tape the sides of the screen d. Place the funnel into the neck of the square-sided bottle e. Put the leaf litter sample at the top of the funnel f. Place a lighted 40 watt lamp above the funnel with an incandescent bulb about 1-2 inches from the top of the leaf litter g. Cover everything with foil 12. Leave the lighted setup on the lab bench for a week

Raw Data The first plant was retrieved from what has been previously been labeled as pod 6, in the far east section of the transect (Figure 8). The plant has three leaves, with a long stem, the plant is green in color and each leaf is on average two inches long and a an inch wide (Figure 11). This plant is vascular because of its roots and how it produces daughter plants. Three leaves per stem, the leaves are edged with ridges. There were no seeds or evidence of flowers, it appears to be a weed. The second plant was retrieved from the outer edge of what has been previously been labeled as pod 3, in the far east section of the transect (Figure 5). The plant has five leaves, with a stem, it is green in color and each leaf is on average and inch and a half long and a quarter of an inch wide (Figure 12). This plant is vascular because of its roots and how it produces daughter plants. The five leaves are long and skinny, they also have many ridges on the leaves and there are veins running through them. There were no seeds or evidence of flowers, it appears to be a weed. The third plant was retrieved from what has been previously been labeled as pod 6, in the far east section of the transect (Figure 10). The plant is an herb that appears to be classified under the name of Rosemary, the leaves are long and skinny, the plant is tall and This plant is non-vascular has many branches, it is a light green and deep purple in color (Figure 2). This plant is non-vascular. The leaves are abundant for each stem, there is not a specific number of leaves per stem, they are long and skinny, about two inches long and less than a quarter of an inch wide, they have very small ridges with ridges and veins on the surface of the leaves. In the spring and summer time this herb does produce flowers. The fourth plant was retrieved from what has previously been labeled as pod 2 in the middle of the southern portion of the transect (Figure 3). There are five main branches that each have an abundant amount of leaves on them, the plant is green and stands about five inches tall (Figure 13). This plant is vascular because of its roots and how it produces daughter plants. The leaves are abundant on each branch of the plant, they are very small an average of 3 centimeters long and 1 centimeter wide, they form around the entire branch and almost make a flower formation they are smooth around the edges as well as their top and bottom. There were no seeds or evidence of flowers, it appears to be a weed. The last plant was retrieved from what has previously been labeled as pod 4, in the north west section of the transect (Figure 4). There are eight branches each with one green leaf on it, each leaf has purple veins, the plant stands four inches high (Figure 14). This plant is vascular because of its roots and how it produces daughter plants. The leaves are dark green, they have multiple purple veins and have smooth edges, the top and the bottom of the leaves are also smooth, they are on average one inch long and half an inch wide. There were no seeds or evidence of flowers, it appears to be a weed. All of the previous information can be found on Table 1. There were no seeds present at the time of the plant collection but a Lily seed was cut open in lab to observe (Figure 20). The seed from the Lily is a monocot. We also looked at Fungi in lab and one of the most important things in a fungi is the sporangia. Fungi Sporangia is the structure containing the spores in fungal species, they allow the spores to reproduce and ultimately allow the fungi to continue to exist (oxford dictionaries).


Conclusions and Future plans

The different plants in the transect indicates how many species have adapted to different environments. It also indicated how even the slightest different of environment can produce new plant species. In the future I would cross-examine the species against the different seasons throughout the year to see if different species of plants species are present only in certain times of the year or if some species are present throughout the entire year. I would also like to further investigate the different species in the different transects and see if they have any species in common.


Sources: http://oxforddictionaries.com/definition/sporangium

Photos: https://docs.google.com/a/student.american.edu/document/d/1DcrlFtdHl8nQ5lsN6cWgrbbJ9kI0UCDG-rLwQL3juwA/edit

Table: https://docs.google.com/a/student.american.edu/spreadsheet/ccc?key=0Ar2AbpCFgv4xdG40Qy12bW8xSFhmTUNmSWpQZ1NfQ0E&usp=drive_web#gid=0


-KMD


2/15/14

Introduction

The purpose of this week’s lab is to understand the characteristics of bacteria, observed antibiotic resistance and to understand how DNA sequences are used to identify species. This will be done through a series of experiments involving staining, observation, and microscopic observation. The bacteria from the Hay infusion was tested in a dilution, as well as against the antibiotic, tetracycline, to see which bacterias were antibiotic resistant. The gram stain helps to better determine the type of bacteria, either gram positive or gram negative. A gram positive bacteria retains the dye and as a result is a dark purple color, indicating that their cell wall consists of a thick layer of peptidoglycan. A gram negative bacteria does not retain all of the dye, and as a result it is a pink color, indicating that the bacteria’s cell wall consists of a tinnier peptidoglycan and a phospholipid bilayer. By understanding the characteristics of bacteria you can begin to understand how it develops different strains that become antibiotic resistant.

Procedures

1. Obtain a prepared slide containing different types and shapes of bacteria 2. Put a small amount of oil on the slide 3. Observe stained areas of the slide with the lower objectives of the microscope 4. Proceed to view the slide at higher objectives 5. Clean the objective lenses and microscope stage with lens paper 6. Make a wet mount

             (a) Sterilize a loop over a flame and use it to scrape up a tiny amount of growth from the surface of the agar  
             (b) Mix it into a drop of water on a slide
             (c) Place a cover slip over the drop 
             (d) Make a second drop on a second slide 
             (e) Smear a small amount of the colony in the drop over the surface
             (f) Circle the area underneath this slide with a red wax pencil

7. Make sure to label the slides. 8. Pass the slide through a flame three times with the bacterial smear side up 9. Cover the smear with crystal violet dye for 1 minute 10. Rinse off the stain 11. Cover the smear with Gram's iodine mordant for 1 minute 12. Rinse gently 13. Cover the smear with 95% alcohol for 10-20 seconds 14. Rinse gently 14. Cover the smear with safranin stain for 20-30 seconds 15. Rinse gently 16. Blot the excess water with a paper towel and let the slide air dry 17. Observe the slide under 40X


Raw Data

All three domains of life, the Eukarya Domain, the Domain Bacteria, and the Domain Archaea, include unicellular organisms. The hay infusion looked into the Eukarya Domain, which when looked at this week all the sediment in the water had completely settled to the bottom of the jar, the water level had dropped and its color was lighter, there were also white stringy substances floating towards the bottom of the sample. It smelled even worse and stronger than the previous week. The change is most likely due to growth of new organisms or the rotting of the organic materials in the sample. A species from the Domain Archaea will most likely never appear in lab this semester due to the fact that species of the Domain Archaea tend to grow in the most extreme environments, for example the bottom of the ocean or a hot spring. The petri dish experiment done in this weeks lab looked into the Domain Bacteria. The plates without the antibiotic produced bacteria colonies with a lighter yellow color and irregular shape. The plates with the antibiotic produced bacteria colonies with a deep orange color and circular in shape. This leads to the indication that the antibiotic, tetracycline prevents some bacteria from forming and as a result there was a lower number of colonies on the tetracycline petri dishes. Not very many bacteria are resistant against tetracycline, in order to develop a resistance to the antibiotic they have to acquire a horizontal transfer gene that does one of two things, encodes an efflux pump or a ribosomal protection protein (Chopra). Tetracycline works by prohibiting protein synthesis by blocking the binding site of an amino acid that is a part of a t-RNA (Mehta). The first plate was only the nutrient without the tetracycline with a dilution of ten to the negative seven which was the bacteria sarcinae, which is a part of the cocci arrangements (Figure 1 and 4). It is circular, pasty yellow in color, convex, glossy (smooth, and is 2mm in length (Table 2). The second plate was also only nutrient without tetracycline and had a dilution of ten to the negative five, it illustrated the bacteria diplobactilli which is a part of the bacilli arrangements (Figure 2 and 5). It is irregular, light cloudy yellow in color, glossy, and is different sizes and large (Table 2). The third and final plate had the nutrient and the tetracycline antibiotic, it illustrated the bacteria, fusiform bacilli which is also a part of the bacilli arrangements (Figure 3 and 6). It is a deep orange color, circular, convex, glossy, and 1mm in diameter (Table 2). Table one illustrates the number of colonies that are present on each plate containing the dilutions (Table 1). Table 2 also illustrates the number of colonies per ml of culture as well as if the cells are gram positive or gram negative (Table 2).


Conclusion and future plans

The purpose of the dilution and the exposure to the antibiotic, tetracycline, was to determine what types of bacteria were present in the transect. The experiment showed the diverse populations of bacteria and how they grow, move, interact, as well as how they react to antibiotics. The dilutions allowed the bacteria concentrations to be lower and be easier to determine their species. In the future I would let the petri dishes sit longer and compare them against the ones in lab this week to see if more colonies or new species of bacteria have formed. I would also want to use different antibiotics to see how the results very.


Tables: https://docs.google.com/a/student.american.edu/spreadsheet/ccc?key=0Ar2AbpCFgv4xdF9rbzVhbUJWMUYyczFmVmh3cDFEb2c#gid=0

Figures: https://docs.google.com/a/student.american.edu/document/d/1Q-0r2---VdGSsSufXSbmq8EX0DaaBbkcmwG7LWZNF4Y/edit

Sources:

Mehta, Akul (2011-05-27). "Mechanism of Action of Tetracyclines". Pharmaxchange.info. Retrieved 2012-06-07.

Chopra I, Roberts M (June 2001). "Tetracycline Antibiotics: Mode of Action, Applications, Molecular Biology, and Epidemiology of Bacterial Resistance". Microbiol. Mol. Biol. Rev. 65 (2): 232–260. doi:10.1128/MMBR.65.2.232-260.2001. PMC 99026. PMID 11381101.


-KMD


2/08/14

Introduction:

This weeks lab dealt with the system of the dichotomous key as well as to understand the characteristics of Algae and Protists. Algae and protists are two large groups of unicellular eukaryotes. Algae photosynthesize and protists consume nutrients. The Volvocine Line observed in last week’s lab is a good example of an algae. It is important to know and understand the differences between the organisms in order to know how they act and work to better understand the organisms’ role or function in an ecosystem. The dichotomous key helps to identify a group of organisms. It contains a series of two morphological choices based on observed characteristics such as, size, shape, movement, and color. The choices will eventually lead you to an organism which corresponds to a picture where you can check against the organism in which you hope to identify. Finally this lab contains preparing and planting serial dilutions. The dilutions allow for the study of an ecosystems bacteria and its resistance against the antibiotic, tetracycline.

Procedures:

1. Make a wet mount of the sample with the known organisms and observe with the microscope 2. Focus on one organism and characterize it 3. Determine the organisms size with the ocular micrometer 4. Obtain a Key that describes eight known organisms and use it to determine the organism 5. Repeat with a second organism 6. Then carefully bring the Hay Infusion culture to your work area without disturbing it 7. Take a few samples for microscopic observation from different locations 8. Note where you obtain these samples from the culture 9. Use a dropper to place a drop of liquid from the culture onto a slide and put a cover slip on top 10. Draw pictures of the organisms you observe 11. Characterize 3 different organisms from each of two areas of your culture 12. Measure the organisms size with the ocular micrometer 13. Obtain four tubes of 10 mls sterile broth and label them 2, 4, 6, 8 14. Find four nutrient agar and four agar plus tetracycline plates 15. Swirl the Hay Infusion Culture 16. Take 100 mls from the mix and add this to the 10 mls of broth in the tube labeled 2 17. Swirl the inoculated tube well 18. Take 100 mls of broth from tube 2 and inoculate tube 4 and swirl it 19. Repeat two more times to make 10-6 and 10-8 dilutions 20. Take 100 mls from the 10-2 tube and place it on the surface of the nutrient agar plate labeled 10-3 21. Spread the sample on the plate 22. Repeat the exact procedure on the “tet” plate labeled 10-3 23. Repeat this exact procedure with the number 4 tube on the 10-5 plates, number 6 tube on the 10-7 plates and the number 8 tube with the 10-9 plates

Raw Data:

When the Hay Infusion was first obtained the smell was a poignant, sewage, rotten, mildew smell. It had plants hanging from the top, the water was a murky light brown color. There was black sediment at the bottom and light brown sediment around the edges. There seemed to be some mold growing on the top of the water. Some of the selective pressures that could have influenced the hay infusion are the availability of nutrients meaning the amount of plants in the sample, the length of the roots of those plants, the amount of sunlight that was available to the container, the amount of air that it was exposed to, as well as if the water was polluted. I think specimens should be different in different parts of the ecosystem because of the different fitnesses of the organisms. Specimens at the bottom of the sample, were taken from the soil at the very bottom of the sample. One organism that was found was Arcella, it is living protozoa that is colorless and moves (Figure 2). They reside around the sand and dirt particles. They are not completely spherical. The one found in the bottom of the sample was 50 micrometers long. Arcella feed off of diatoms, unicellular green algae or animal protozoa. They are enclosed in an umbrella-shaped cell and can have multiple nucleases. There are multiple species of arcella depending on its environment, they can survive in freshwater pools, eutrophic waters, marshes, mosses, as well as wet foliage. They are the evolved form of the amoeba and is a protist. Arcella reproduce by binary fission (Arcella). Another organism that was found at the bottom of the sample was Euglena, a moving, elongated, green organism with one locomotor flagella (Figure 3). It was 40 micrometers long. Specimens at the middle of the sample, were taken from solution at the middle of the sample. One organism that was found in the middle of the ecosystem was a clopidium which is a fast moving organism with a small, oval-shaped body covered in cilia (Figure 5). It was 55 micrometers long. Another organism that was found int he middle of the sample was a spirostomum, a moving organism with a flattened, elongated body with blunt edges covered in cilia (Figure 4). It was 2 millimeters long. Specimens at the top of the sample were taken from solution at the very top of the sample near the surface of the water. One organism from the very top of the sample was a clopidium, which is described above (Figure 5). Another organism found at the very top of the sample is a paramecium bursaria which is an organism that swims in a corkscrew pattern and has a round, cigar-shaped, elongated body that is covered in cilia (Figure 6). Another type of organism that can grow in an ecosystem is bacteria. The best way to look and observe bacteria is in cultures and how they respond to antibiotics. The bacteria are in such high concentrations that they need to be diluted before they are cultured. The serial 100-fold dilution is what worked for this lab’s culture (Figure 1).

Conclusions and future plans:

The conclusions of this lab consist of the fact that the experiments revealed that different organisms live in different environments within an ecosystem. This makes sense, there are many different organisms that live in one ecosystem, this can be seen very easily in an ecosystem such as a pond where there are fish, frogs, different insects, and many other organisms. However, this lab showed that this is also true on the microscopic level. Some organisms have a higher fitness for living near the bottom of the liquid solution, maybe they rely on the sand or soil at the bottom for camouflage. Some organisms have a higher fitness living in the middle of the liquid solution, and some may need more oxygen or sunlight and as result have a higher fitness near the top of the liquid solution. If the infusion were to sit and be observed for another two months I would expect the water to become more murky and bacteria and mold to be in large quantities. In addition, the dichotomous key revealed itself as a useful tool in identifying the different organisms in the ecosystems. In the future, I would like to cross examine the organisms found in all of the different ecosystems by all the groups in lab and see if there are any commonalties or differences in the organisms that were found and where those particular organisms were found.

Link to photos: https://docs.google.com/document/d/1iiHIrQ0Qlm3xJa9eRlDAwC1yzSnlyLdMESYYpzrxDiQ/edit?usp=sharing

Sources: http://www.arcella.nl/arcella

-KMD


2/6/14, lab 1notes

GREAT characterization! Make sure you upload pics from lab 1 and lab 2 by Sunday. Also, start working on building a map of your transect to detail your land and where your samples are taken from. We will talk about this more Wednesday. awesome job!

AP

1/28/14

Introduction:

This weeks lab dealt with the theory of evolution introducing concepts such as natural selection, genetic drift, a founding population, and population genetics. The purpose of this week’s experiment was to begin to determine if different types of ecosystems yield different species. To achieve this three organisms from the same line were observed for differences and speciations. The second part of this lab worked to gain an understanding the environment in which organisms evolve to or their ecosystems and niches. Concepts such as a species, population, community, abiotic and biotic organisms, and biodiversity were discussed and studied. This was done by groups being formed and assigned to a location on American University’s campus to be sampled and studied. In addition this lab taught how to properly obtain soil and ground vegetation samples as well as prepare the samples for future study and make thorough and insightful observations of an ecosystem.

Procedures:

1. Prepare a slide of living Chlamydomonas with protoslo to slow them down and examine it under a microscope 2. Record the number of cells that were found, the colony size, any functional specialization of cells, and determine if the organism reproduces isogamy or oogamy 3. Prepare a slide of living Gonium and examine it under a microscope 4. Record the number of cells that were found, the colony size, any functional specialization of cells, and determine if the organism reproduces isogamy or oogamy 5. Prepare a slide of living Volvox and examine it under a microscope 6. Record the number of cells that were found, the colony size, any functional specialization of cells, and determine if the organism reproduces isogamy or oogamy 7. Obtain a sterile 50 ml conical tube from the lab 8. Locate assigned transect on campus with assigned group 9. Fill the sterile 50 ml conical tube with soil and ground vegetation from different locations on the transect 10. Make observations in lab notebook about the appearance and contents of transect 11.Go back to the lab once the lab instructor checks your work 12. Obtain a plastic jar 13. Weigh 10 to 12 grams of the soil/ground sample and place it in the plastic jar 14. Measure 500 mls of deerpark water and add it to the plastic jar 15. Weigh and add 0.1 gm of dried milk to the plastic jar 16. Stir the contents of the plastic jar gently for 10 seconds 17. Remove the top of the plastic jar and place it in the indicated place in lab to be used for next weeks lab


Raw Data: The transect It is a twenty foot by twenty foot area of terrain in the North side of campus. It is East of the basketball courts, North of the Sports Center Annex building, West of the Wesley Theological Seminary, and is a part of the American University Community Garden. When looking from the entrance of the garden the transect is slanted slightly to the right, meaning that it is not flat. The transect contains six isolated pods sectioned off by four pieces of plywood (Figure 1,2,3,4,5,6,10,12,13,14). Each of the pods is 6” high and contains its own soil. The pods purpose is to contain different plants ranging from flowers, spices, herbs, fruits, and vegetables, however, it was not clearly indicated as to what if anything was being grown in the different pods. Four of the six pods in the square did not appear to have anything growing in it, however, further testing of the soil or the passing of time would provide a clearer insight as to if there is anything growing and if there is what is being grown. The fifth pod contained some green foliage but we were unable to identify it on the sight, we took a sample so that it could be further looked at in lab (Figure 11). The sixth pod was full of different types of foliage, by the smell we identified of the plants as the herb Rose Mary, however, further testing of the plant would confirm the plants identity (Figure 7, 8). The other foliage we were not able to identify upon first examination (Figure 9). We took samples from each of the plants so that we would be able to identify them in lab. Between the six pods there is dark brown soil covered in wood chips. The abiotic components identified in the transect were, water, dark brown soil on both the ground and in the six pods, sunlight, air, wood, rocks, and we also speculated that because of the presence of the garden and the trends of modern society, that there were also pesticides present. The biotic organisms identified were bacteria, microbes, vegetation (herbs, weeds), worms, and vegetables.

Conclusion and Future Plans:

When observing the three different organisms in the Volvicine Line the farther down the line the organism that was observed was the more cells it had and the more specialized it was. The Chlamydomonas is at the very beginning of the line and is single celled and has an isogamous reproduction speciation. On the other hand, Volvox is at the peak of evolutionary complexity for the Volvicine line and is multicellular and has an oogamy reproduction speciation. The soil samples that were obtained from the specific transect are fully prepared for observations and conclusions to be made about the organisms they contain next lab through a Hay Infusion. Because the soil needs to settle and react to the water and dried milk, the observations and conclusions could not be made in this weeks lab and will be conducted at the beginning of next weeks lab.

link to the photos: https://docs.google.com/a/student.american.edu/document/d/1zA_06YV1rZj4B6rX7SElL1HbgPB0YX52Zy7I5kPFnQ8/edit?usp=sharing

-KMD


01/22/14

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-KMD

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