Relationship Between Amounts of Zooxanthellae
Intertidal Zone Distribution in Anthopleura
xanthogrammica
Bi 3B
Patricia Seabourne
and
Introduction
Zooxanthellae are photosynthetic algae that inhabit the endodermal tissues of their
hosts (Weiss 10996). Anthopleura xanthogrammica is common in the lower and middle
intertidal zones in the west coast of North America, and it forms symbiotic relationships
with photosynthetic algae. The color of the algae makes the anemone brownish green.
Anemones with Zooxanthellae can be found throughout the intertidal zone, but favor the
upper levels (Bates 2000; second et al. 2000). Bates explains that high-shore individuals
of A. xanthogrammica tend to have predominantly Zooxanthellae and are brownish-green
in color. Zooxanthellae favors higher temperatures and higher light conditions. In order
to determine the relationships between amounts of Zooxanthellae present and intertidal
zone distribution, I developed the hypothesis that A. xanthogrammica living in the middle
intertidal zone, contain higher amounts of Zooxanthellae.
Methods
Six tentacles were collected at Aliso Creek Beach, Laguna Beach, California, and
six tentacles were collected at Woods Cove, Palos Verdes, California. I wane to Aliso
Creek Beach during the lowest tide (Lowest tide=1.2) and started collecting tentacles at
the lowest point of the intertidal zone. I walked toward the bottom of the lower zone,
found an animal. And cut a tentacle. . Then, I continued walking until I found another
anemone, and I cut another tentacle. It was difficult to cut tentacles from anemones that
were contracted, thus I avoided those. I also avoided anemones I found in crevices, and
under rocks. I continued walking the lower intertidal zone until I collected six tentacles
from six different A. xanthogrammica. Then, I moved to the middle zone and I began
collecting six tentacles in the same manner. Collection at the Palos Verdes location was
carried in the same way with a low tide of -0.6. After collecting the samples, I placed
them in plastic containers and immediately froze them. Tips of A. xanthogrammica were
used for analysis. All tentacles were cut into the same volume (0.2 grams), placed in an
Eppendorf tube, and dipped in a 15 ul of distilled water. The tentacles mixture was
homogenized using a glass rod, and the density was calculated. The mixture was placed
in a hemacytometer under a light microscope. The number of Zooxanthellae was counted
in eight squares. Then, the cell concentration was calculated by dividing the average cells
in the eight squares by the volume of a square. The final Zooxanthellae volume was
calculated by dividing the obtained density multiplied by the initial value by the
recommended cell density.
Results
Anemones with a higher concentration of Zooxanthellae were observed in the
higher intertidal zone, or middle zone, while the anemones with the lower concentration
of Zooxanthellae were observed in the lower intertidal zone.
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For the graphs, you need to follow the correct format for bio papers. This includes getting
rid of the black border on each graph, getting rid of the back lines, changing the color of
each sample, fixing the error bars to go higher and lower than the value, add axis titles
and define the units for each axis title, etc, etc. Use some of the other papers as examples
on how your graphs should look.
Figure 1. Amount of Zooxanthellae in Lower Intertidal Zone and Middle Intertidal Zone.
Correlation between amount of Zooxanthellae and tidal zone distribution was clear. The
mean amount of Zooxanthellae present in anemones from the middle intertidal zone was
higher. (Figure 1).
You need to include figure caption for each graph; you have two graphs; therefore, you
should have two figure captions.
Discussion
The location in the intertidal zone seems to affect the number of Zooxanthellae
present in the anemone; the anemones with a higher number of Zooxanthellae seem to
prefer locations in the middle intertidal zone, and the anemones with lower numbers of
Zooxanthellae are more likely to be found in the lower intertidal zone. As Bates (2000)
mentioned, anemones with Zooxanthellae are usually found in the higher intertidal zones.
Higher numbers of Zooxanthellae found in anemones further from the water ay help
anemones survive better. Also, anemones can always find a crevice or shaded area where
to hide. These shaded microhabitats may help the Zooxanthellae survive.
While
collecting specimens of A. xanthogrammica, I only chose specimens exposed to the sun
and light, thus my results indicate the amounts of Zooxanthellae found in anemones
which are exposed. If tentacles were collected from anemones found in shaded areas, the
results may differ. The amount of Zooxanthellae seems to be directly correlated to the
amount of Zooxanthellae present in the anemone. Figure 1 suggests that the standard
deviation and mean standard error is also lower for anemones found in the middle
intertidal zone. Figure 1 also indicates that middle zone anemones have the higher mean.
This result supports my hypothesis that anemones with higher concentrations of
Zooxanthellae are more likely to be found in higher intertidal zones. Even though my
results support my hypothesis, some points should be mentioned. All the results are based
in samples collected from anemones exposed to sunlight. If the tentacles would have been
collected from specimens living in shaded areas or crevices, the results might have been
different. Also, counting Zooxanthellae cells using an hemacytometer needed to be done
very precisely. Counting errors can alter the results significantly. There is still a lot to
learn about the relationship between tidal zone distribution and amounts of
Zooxanthellae.
Key
Spelling/Punctuation Errors
Consider Rewrite/Read Comment
Add in/ advisement
Things that are forgotten in this Essay that are needed to be added
Review Form
Department of Biological Sciences
Saddleback College, Mission Viejo, CA 92692
Author (s): Patricia Seabourne
Title: Relationship Between Amounts of Zooxanthellae and Interidal Zone Distribution in
Anthopleura Xanthogrammica
Summary
Summarize the paper succinctly and dispassionately. Do not criticize here, just show that you understood the paper.
Patricia looked into the amount of zooxanthellae – a photosynthetic algae – in the
tissues of a sea anemone called Anthopleura Xanthogrammica. The presence of this algae
can be seen thorugh a brownish-green color in the anemone. The algae is present in areas
with higher temperatures and light conditions. She hypothesized that A Xanthogrammica
living in the middle intertidal zone will contain higher amounts of the Zooxanthellae
algea.
Six tentacles were collected from an anemone from Aliso Creek Beach and
another six from Woods Cove. The tentacles were collected from Aliso Creek during
lowest tide. A total of 12 tentacles were collected, 6 in the middle zone and 6 in the lower
zone. The Palos Verdes samples were collected during a low tide. The samples were
collected in containers and frozen. The final Zooxanthellae volume was calculated using
the cell concentration using eight squares.
It was found that anenomes with higher concentration of Zooxanthellae were in
higher intertidal zone and the anemones with lower concentration were found in lower
intertidal zone. The mean amount of Zooxanthellae present in the anemones from the
middle zone was higher than the lower zone. The location of the intertidal zone seemed to
affect the number of zooxanthellae present. A study found that these anemones are able
to survive better in higher zones.
General Comments
Generally explain the paper’s strengths and weaknesses and whether they are serious, or important to our
current state of knowledge.
Strong Points
There was good background in introduction, and good explanation of the things being
studied in this experiment. I felt like there was a clear hypothesis that was easy to follow.
I also found the discussion to be very descriptive and helpful as well. A lot of other
scenarios and situations were described in the discussion. The whole paper was very
descriptive of what Patricia was doing.
Weak Points
Many grammatical errors and punctuation problems exist in this paper. It seems like it
hasn’t been read over once for mistakes. Like I said before, the hypothesis is clear yet it
can be reworded. The methods needs to be a little bit more clear: For instance, I am a bit
confused on how many samples you collected from the anemones. I am also unclear on
how the number of Zooxanthellae were calculated. The results section needs reworking.
The graphs are incorrectly formatted. And both the discussion and the results needs
Quantitative data (actual numbers).
Technical Criticism
Review technical issues, organization and clarity. Provide a table of typographical errors, grammatical
errors, and minor textual problems. It's not the reviewer's job to copy Edit the paper, mark the
manuscript.
This paper was a final version
Section
Introduction
[X] This paper was a rough draft
Errors
Spelling
Grammatical
Repetition
Lack of Information
Unclear
Spelling
Grammatical
Lack of Information
Grammatical
Needs Statistical Analysis
Needs work on Figure Captions
Needs quantitative Data
Needs Format fixing on Graph
Needs another fig Caption
Grammatical
A little unclear
Unorganized, thoughts aren’t
organized/oriented
Methods/Materials
Results
Discussion
**CHECK KEY**
Recommendation
 This paper should be published as is
[X] This paper should be published with revision
 This paper should not be published