User:Madison Prieto/Notebook/Biology 210 at AU

January 22, 2016 Exercise 2: Identifying Algae and Protists

Purpose The purpose of this lab is to use a Dichotomous Key to identify protists from our Hay Infusions and to know the defining characteristics of protists. We also identified the characteristics of the protists in our transect. We then did serial dilutions to plate the bacteria and characterize the bacterial diversity.

Materials and Methods Procedure one involved making a wet mount from the Hay Infusion to observe with the microscope at 4x and 10x. Focus on an organism, describe it, and record its size. Use the Dichotomous Key to identify organisms. Procedure two involved prepare for next week’s microbiology lab by preparing agar plates.

Data and Observations

Our Hay Infusion was filled halfway with brown dirty water. There was some dead plant life sitting at the bottom on top of sand or dirt that had collected at the bottom of the jar. All of the plant life looked destroyed. There was a sort of film over the surface of the water. We took samples from the top, middle and bottom of the Hay Infusion and viewed the samples under a microscope.

We used the Dichotomous Key to determine what protists were living in our Hay Infusion.

Description of cell from bottom of hay infusion:

-Cell is colorless

-Cell is stagnant

-Cell is not spherical

-Shape of cell remains constant

-Seems as if cell has very thick cell walls

-Parts of cell would range from 2-30 ocular spaces at 100x

This protist sample is a type of algae known as Pandorina.

Description of cell from middle layer of hay infusion: -4 ocular spaces (at 10x objective) -small body -oval shaped -fast swimmer -Colpidium

Description of cell from top layer of Hay Infusion: -random, quick movements, -cell compresses as it is moving -10 ocular spaces -Stentor

Another cell from top layer of Hay Infusion: -5 ocular spaces -colonies -Gloeocpsa

Another cell from top layer of Hay Infusion: -150 ocular spaces -resembles a large blob -Hydrodictyon

M.P.

January 15, 2016 Exercise 1: Examining Biological Life at AU

Purpose The purpose of this week's lab experiment was to examine and compare different members of the Volvocine Line and to examine the biodiversity on the campus of American University. At the end of the lab, we set up a Hay Infusion with abiotic and biotic compontnets found in our transect.

Materials and Methods Procedure one involved examining members of the Volvocine Line: Chlamydomonas, Gonium, and Volvox. We recorded the colony size, number of cells, specialization of these cells, and whether the cell was isogamous or oogamous under the microscope. Procedure two involved going to our transect and recording everything we observed. We also took samples of our transect and brought the samples back to the laboratory. Procedure three involved making a Hay Infusion. To do this, we placed 10-12 grams of our sample into a jar with 500 mLs of deerpark water, added 0.1 gram of dried milk, and mixed the jar for 10 seconds.

Data and Observations Transect Four included many different biotic and abiotic factors. The abiotic factors included rocks, water, soil and benches. The biotic factors included trees, bushes, flowers, fishes, and many organisms. This transect was interesting to survey and collect from. There is so much plant life and animal life, although we were only able to view the organisms under the microscope. A majority of the plant life was wilted and brown due to the cold weather.

Sketch of Transect Four:

Images of Transect Four:

Conclusion Transect four had many abiotic and biotic components to it. These abiotic and biotic components will help us examine the biodiversity at AU. Further experiments will show the different types of organisms that live in transect four at American University.

M.P.