User:Portia P. Ofori/Notebook/Biology 210 at AU

1/21/16

Header: Hay Infusion culture observations.

Purpose: To observe the invisible world of unicellular eukaryotic organisms under a microscope and use the dichotomous key to identify protest and algae.

Hypothesis: Organisms in the various niches of the hay infusion will exhibit slight differences between them.

Materials: Microscope slides, cover slips, microscope, plastic pipette.

Method:

-Obtain three clean microscope slide and put a drop of the specimen from each niche.

-Cover with a cover slip and observe with a microscope at 4X and 10X.

-Use the 40X for resolution. Record the sizes using ocular micrometer

-Obtain a dichotomous key and use it to determine organism present.

Observations: The hay infusion culture appeared cloudy with a pungent smell. The hay infusion had changed color to light brown with three distinct layers. Molds were present on top of the liquid. There were no green shoots present. Fine granular-like sediments were seen at the bottom layer.

Organisms differ close to verses away from plant matter because they have different carrying capacities (the maximum number of individuals of species that can survive in a particular niche)

Using the dichotomous key to identify 3 different organisms from three niches in the hay infusion.

Top niche:

Paranema: Cell elongated, colorless with a broad or truncate posterior during locomotion. Highly plastic when stationary, often appears to vibrate when in motion. Amoeba: Small, creeps using pseudopodia and has a single disc shaped nucleus. Actinosphaerium: Colorless organism sliding slowing without apparent motion, spherical shaped with radiating spines.

Middle niche:

Colpidium: Small body, oval shaped and covered in cilia. Fast swimmer. Paranema: Cell elongated, colorless with a broad or truncate posterior during locomotion. Highly plastic when stationary, often appears to vibrate when in motion. Pelomyxa: large, creeps using pseudopodia, many (100s) of small nuclei.

Bottom niche:

Chilomonas (algae genus): Colorless, cells organ of locomotion is a long whip-like flagella (no cilia), single motile cell, 2 observed locomotor flagella at one end, cell elongated with narrowed posterior. The cell measures 20 ocular spaces using 40X objective lens. Paranema (protozoa): Cell elongated, colorless with a broad or truncate posterior during locomotion. Highly plastic when stationary, often appears to vibrate when in motion. Chlamydomonas (Algae): Cell is greenish, a single motile cell, two observed locomotor with an oval shaped body. The green color suggest photosynthetic activity.it measures around 10μm.

Description of how Chlamydomonas meets all the needs of life as described on page 2 of the freeman text. Chlamydomonas has photosynthetic activity therefore absorbs sunlight as its source of energy. It has a cell membrane that regulates the passage of materials in and out of the cell. Chlamydomonas has a flagella which aids in movement. It can undergo both sexual and asexual reproduction.

If the hay infusion grew for another two months my prediction will be a reduction in the number of organisms present. Struggle for resources through which organisms survive and pass on genes to the next generation will be very evident. One selective pressure that will affect the community of my sample will be limitation of nutritional resources leading to competition for food and energy among microorganisms. Therefore if certain organisms have a lower chance of survival, they cannot stay alive to reproduce.

Diagrams of organisms observed in the different niches.

Header: Serial Dilutions.

Purpose: To prepare and plate serial dilutions of organisms in the hay infusion nutrient agar and enriched agar.

Materials: Four test tubes containing 10ml of sterile broth, micropipette set at 100μl, micropipette tips, four nutrient agar petri dishes, four nutrient agar with tetracycline petri dishes, test tube rack, inoculation spreader, Bunsen burner.

Method:

-Swirl hay infusion to mix up organisms.

-Aliquot 100μl of sample from hay infusion and add to 10ml of sterile broth (10-2 dilution)

-Swirl inoculated tube to mix and add 100μl from 10-2 dilution to 10-4 tube.

-Repeat above step to make the 10-6 and 10-8 serial dilutions.

-Pipette 100μl and inoculate on both nutrient and nutrient agar with tetracycline for each of the serial dilutions

-Place agar plate in a rack with the agar side facing up.

-Incubate at room temperature for one week.

Diagram of serial dilution procedure

1/14/16 Observation of a 20/20 transect

Location: The transect is located in an area behind the AU library close to the student health center. It is a 20 by 20 foot dimension marked with four Popsicle sticks with a pond at the center.

Topography: The transect had Cornus florida commonly called flowering dogwood, Parrotia persica treesome trees and some budding flowers as well. The soil was moist and covered mostly with fallen leaves. The sides of the pond was riprapped with rocks to protect it from wind, wave action and erosion. There were grass grown around the pond probably to prevent erosion.

Biotic Components: 1. Pond 2. Two big trees without leaves 3. Three short trees with green leaves and budding flowers 4. Mushrooms 5. insects

Abiotic component of transect: 1. Bamboo grid used to cover the pond 2. Net used to cover the pond. 3. Classroom block. 4. Lights form the classroom wall 5. Two lovers seats 6. Two statues ( Duck statue in the pond and a woman with three birds at her feet on land) 7. Irrigation control valve just above the pond. 8. Deflated balloon on land 9. Paper on land 10. Wiring that goes into the pond 11. Large and small rocks outlining the pond

Characteristics	Chlamydomonas	Gonium	Volvox
Number of cells	1	4	1(containing many smaller cells)
Colony size	4os / 10μm	8os /22μm	22os / 220μm
Specialization of cells	Unicellular, egg-shaped, cup-shaped chloroplast	Gelatinous matrix	Multicellular, presence of spiked cells
Mechanism of motility	Flagella	Flagella	Flagella
Isogamous or Oogamous	Isogamous	Isogamous	Oogamous

Pictures from the transect.

Aerial diagram of the transect