1. Presented by: Randy McCroskey Lauren, Selima, Kelli, Lacey
Coral Bleaching
Group 2
Presented by: Randy McCroskey
Lauren, Selima, Kelli, Lacey
When ZOOX hit the HIGH SEAS!

2. What are Zooxanthellae?!
Yellow, Brown Dinoflagellate Algea
Live symbiotically in the gastrodermis of reef-building coral
Zoox provide nutrients needed for growth in form of photosynthetic products
Coral provides protection and access to sunlight
Zoox in gastrodermis pockets of Coral

3. Possible Bleaching Stressors Include:
Light Intensity
Salinity
Temperature
UV Radiation
Stressors cause coral to secrete their zooxanthellae resulting in the bleaching effect.

4. UV Radiation will have no effect on Zooxanthellae density .
Null Hypothesis
UV Radiation will have no effect on Zooxanthellae density .

5. Anemone Tested : Aipstasia
Small, Light-brown Anemone of the species A. Pallida and A.Pulchella.
Typically less than 1.5”.
Semi-transparent (Glass Anemone)
Photosynthetic but will also consume prey small enough to catch.
Found in Tropical and Sub-tropical oceans worldwide.

6. Phylum: Cnidaria Class: Anthozoa Order: Actiniaria Family: Aiptasiidae Genus: Aiptasia (often spelled Aptasia).

7. Protein concentration will be calculated using the Bradford Assay
Experimental Design
Set up two tanks each containing a relatively equal amount of Aipstasia. One will serve as the Control Tank and the other will serve as the Experimental Tank.
Experimental tank will be equipped with a UV light bulb emitting 358nm and will be left to radiate for the duration of data collection.
The following factors will be measured periodically from Aiptasia in both the Control and Experimental tanks. The data will be analyzed to make conclusion concerning hypothesis.
Zooxanthellae density will be calculated by homogenizing polyps and utilizing a microscope hemocytometer to count cells.
Portion of homogenate will be mixed with acetone, vortexed, centrifuged, and the supernatant put into a light spectrometer to measure the amount of chlorophyll.
Protein concentration will be calculated using the Bradford Assay

8. Control Raw Data Zooxanthellae Count and Chlorophyll Concentration
Protein Concentration

9. Control Analysis Mean Protein Concentration 1.597913119mg/g
Approximately 1.6 billion mg of protein per gram of Aipstasia.
Mean Zooxanthellae Density
z/g
Approximately 207 billion zooxanthellae per gram of Aipstasia.
Mean Chlorophyll Concentration
x106 mg/ml
Approximately 35,000 mg of chlorophyll per ml of Aipstasia.

10. Experimental Raw Data
Zooxanthellae Density and Chlorophyll Concentration
Protein Concentration

11. Experimental Analysis
Chlorophyll Concentration
,000 mg/cell Control
,000 mg/cell 35,000mg/cell
,000 mg/cell
40% Decrease!
Zooxanthellae Density
Billion z/g Control
Billion z/g Billion z/g
Million z/g
80% Decrease!
Protein Concentration
mg/g Control
mg/g mg/g
mg/g
84% Increase?

12. What does ALL this MEAN?! Overview:
Zooxanthellae Density and Chlorophyll Concentration both decreased significantly from the first experimental group to the last; however, protein concentration increased an ample 84%. The UV radiation seems to have effected the aipstasia yet it is still producing protein which requires energy that is provided by zooxanthellae metabolic byproducts. If zooxanthellae is not producing chlorophyll, what is it producing?!

13. Microsporidian Amino Acids
“Natures Sunscreen”
Shallow-water environments of tropical coral reefs are characterized by high levels of ultraviolet-A (UVA, nm) and ultraviolet-B (UVB, nm) radiation. This is due to the thinness of the earth’s ozone layer near the equator and to the UV-transparency of tropical ocean waters.
MAA’s were extracted from the experimental aipstasia using methanol alcohol solution and centrifuged. The supernatant was placed in a spectrometer to measure wavelength absorption. The results are displayed in the following graphs.
UV light can penetrate up to 20 meters. Coral tissue must be clear in nature in order for the zooxanthellae to photosynthesize; thus, rendering coral tissue susceptible to harmful amounts of UV light.
In DEFENSE, zooxanthellae produce MAA’s which absorb high amounts of excess UV radiation.

17. Graphs have a local maximum of absorption at 450nm.
Graph Observations
Experimental absorption is higher than in control possibly due to elevated UV exposure.
Graphs have a local maximum of absorption at 450nm.
From first to last experimental group, the amount absorbed decreases. This may be due to decreased production of MAA’s.
Explanation: The zooxanthellae seem to be exerting more metabolic energy on producing MAA’s instead of photosynthesizing which in the long run will weaken the coral, decreasing zooxanthellae count, decreasing amount of MAA’s being made, making coral more and more susceptible to the UV, ultimately bleaching and killing the coral.

18. Bleaching did not occur instantaneously with zooxanthellae density decrease.
Null Hypothesis was rejected. Increased UV exposure decreased zooxanthellae density.
Discussion
Increased UV radiation is then said to act as a photoinhibitor for a period of time. Prolonged exposure may exhaust coral energy/nutrients and bleaching may occur resulting in coral destruction.
Zooxanthellae produced microsporidian amino acids to absorb harmful UV light. Seemingly devoting more metabolic energy creating MAA’s instead of photosynthesizing.

19. THE END