The objective of this study was to test the phototactic response of Daphnia when exposed to red (>600 nm) and white light. A 30 x 2 cm clear acrylic mesocosms with a 10 cm counting area was filled with distilled water and 10 Daphnia. We counted the number of Daphnia that traveled to the lit counting area after 10 minutes. There were twice as many Daphnia in the lit counting area for the control (white light) compared to the experimental group (red light). The results showed that red light had a negative effect on the phototaxis of Daphnia.
Introduction: Daphnia play a vital role in the ecosystem because they are an important part of the aquatic food web (Miner et al., 2012). When exposed to UV light, Daphnia swim deeper into the water (Morris et al., 1995). This natural movement is called phototaxis.
Daphnia have been utilized as test subjects due to their simplicity and how environmental disturbances have impacted their ability to survive, including UV light. Research has shown that Daphnia exhibit a positive
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Therefore, high exposure is harmful to the aquatic environment, especially for species that reside in shallow water, such as Daphnia (Rautio and Korhols, 2002). This phototactic response is attributed to Daphnia’s natural instinct to protect their internal organs and DNA (Morris et al., 1995). Visible light also aids in repairing the damaged nucleotides that are caused by over exposure of UV light (Morris et al., 1995). Even though their behavior is studied often, there is still little that is known about the physiological effect of visible light on Daphnia (Hylander and Hansson, 2010). Daphnia move away from the visible light due to the UV exposure at different rates, but as the visible light increase, so does the rate at which they move away (Storz and Paul,
For this lab, zeolite and magnetized zeolite were synthesized and compared with charcoal to find out with would be the most effective in the sequestering of Procion Red dye. Finding the concentration and absorbance of each zeolite, magnetized zeolite, and charcoal, along with a calibration curve, the best adsorbent is determined. Charcoal was the overall best sequestration of the Procion Red dye, since the adsorbent was highest compared to the others. Introduction Pollution has increased in the environment over the years, so the purpose of this experiment is to find the best adsorbent of chemicals to reduce the pollution.
In this experiment Lumbricus terrestris are being tested for their different types of breathing habits and carbon dioxide release. The Lumbricus terrestris were placed in different a container and placed in one incubator to find the carbon dioxide levels when put in heat. After the Lumbricus terrestris sat for 2 minutes, they would be placed within the incubator with the CO2 sensor attached to the container. This procedure was produced 5 different times. If the temperature is increased, then all the Lumbricus terrestris will release more carbon dioxide into the air or CO2 sensor.
Loggerhead sea turtles face many dangers including artificial lights, which contribute to their endangerment. The most prevalent way loggerhead sea turtles are being threatened is by human interaction. Humans turn on lights by the beach at night sometimes in turtle nesting season, and this can influence female turtles to avoid the beach, where they need to lay their eggs. (“Please turn your lights off, the turtles are nesting: ensuring that federal, state, and local laws help guide endangered marine turtle hatchlings in Florida to the right source of light”). However, there are some actions humans can take to help prevent endangerment of sea turtle hatchlings.
Climate change has been clearly shown to affect Pacific salmon, and it has been generally seen to diminish salmon populations. In the Pacific Northwest, numerous salmon populations have been labeled as endangered under the Endangered Species Act. This is due to climate change warming the ocean, increasing sea levels, and changing flow patterns. It is predicted that salmon populations are only going to continue decreasing due to these changes in their environment. However, some researchers are arguing that Pacific salmon populations are actually going to show an increase in population size, and this is due to an increase in ocean temperatures causing a bottom-up effect that increases resources lower on the food chain, therefore benefitting salmon
The sunlight also affects the amoeba. The amoeba doesn't like much sun because it might dry it up or overheat it. Some biotic factors are its recycling, purifying, and fertilizing. They are a natural source for purifying water and are very helpful in their ecosystems.
The dark Euglena as previously mentioned contain mitochondria, which is responsible for converting chemicals such as oxygen and glucose into useable energy however as simple, unicellular organisms these protists rely on sourcing these chemicals from other organic compounds. As a result of the use of chemicals sources in their environment to carry out oxidative processes, supplying the cell with energy, the dark Euglena are considered chemoheterotrophs opposed to a photoautotroph that sources light energy without the use of other compounds (Engelkirk, et al., 2011). Therefore, because the Euglena gracilis cells are capable of exhibiting both chemoheterotrophic and photoautotrophic characteristic, the organism is classified as a
Corotto, F., Ceballos, D., Lee, A., & Vinson, L. (2010). Making the Most of the Daphnia Heart Rate Lab: Optimizing the Use of Ethanol, Nicotine & Caffeine. The American Biology Teacher , 176-179. The purpose of this article was to test the effects of chemicals on Daphnia magna.
The diversity throughout the animal and plant kingdom is astonishing, is it not? Especially in the oceans, where we only discovered a handful of creatures. However, out of that handful, mankind has learned so much. With that knowledge, comes the desire to protect and preserve each and every precious life discovered. Whether that’d be a Madagascar Lace plant or a Sunfish; they are all important.
If the A.tenebrosa was not able to withstand the strength of the ocean’s waves as they crash into the intertidal zone then the organism would be swept away with the tide off the rocks. The final abiotic factor that I wish to discuss effecting the actinia tenebrosa is light intensity. Light intensity caused from the sun has a large effect on this species. The A.tenebrosa, if exposed to high levels of light intensity, would dry out rather quickly due to the intensity of heat and light from the sun. To avoid this the A.tenebrosa lives under crevices, gullies or other rocks which are damp and usually shaded to avoid desiccation caused by the sunlight.
She also notes that dinoflagellates “are seasonally abundant and are one of the primary causes of red tides, seawater bioluminescence, and shellfish poisoning” (Anderson).
When pelagic cnidarians occur in great abundance, stinging can occur at epidemic levels. As human populations and recreational activities continue to increase along the coasts, stinging is projected to become an increasing problem (Macrokanis et al. 2004). Fourthly, Cultural eutrophication, Eutrophication is considered to be one of the major global pollution problems (e.g. Howarth 2002). Eutrophication is associated with increased nutrients, altered nutrient ratios and increased turbidity where humans develop coastal areas. Most simply, increased nutrients often lead to greater biomass at all trophic levels (Daskalov, 2002).
They are common occupants in freshwater ecosystems like eutrophic lakes, rockpools, ponds but also in more brackish waters (Ambler, Cloern, & Hutchinson, 1985; Hebert, 1978). As outlined before, these habitats are unpredictable with wide fluctuations in abiotic factors, for example in salinity, temperature, acidity (Ph) and oxygen concentration (Ganning, 1971). Daphnia in general are primary planktonic grazers at the bottom of the food web, which makes them a key role species in aquatic ecosystems (Ghazy, Habashy, Kossa, & Mohammady, 2009). They are key role herbivores and are capable of affecting algal populations (Lampert, Fleckner, Rai, & Taylor, 1986), and they are important prey species for vertebrate and invertebrate predators (Bezirci et al.,
The changing of UV irradiance can affect primary production in all ecosystems, terrestrial and aquatic, natural, managed, or exploited with a potential cascade of effects. Current understanding of these processes does not enable confident prediction of the impacts. Chapin, Sala & Huber-Sannwald (Scenario 2013) pointed that “little is known about the effects of increasing UV-B on either biodiversity or ecosystem function”. It is necessary to consider as positive as negative impact of UV radiation on living organisms and
The imbalance in the exchange of nutrients between the zooxanthellae and the host coral reduces light penetration to the reef due to nutrient-stimulated phytoplankton growth, and, most harmful of all, may bring about proliferation of seaweeds (Dubinsky, 1996).Nevertheless, the study had discovered that the coral capable to recover and revive once the nutrients supplies stopped. Last but not least, various chemicals of pesticides and fertilizers from agriculture practices are flowing into the water cycle via soil infiltration and surface run-off. One of the most critical threats
It is important that coral reefs recover once they have been damaged, some of the consequences are; less diverse reef communities, decline in fisheries, tourism and coastal protection (Hoegh-Guldberg et al, 2007). There are 5 potential predictors for how well a coral reef will recover after bleaching (Graham, Nash & Kool, 2011). Firstly, the reef characteristic, if the skeleton of the reef is still present it is likely to maintain ecological processes and therefore recover rapidly (Graham, Nash & Kool, 2011). Secondly, the connectivity of the reef, high connectivity of coral reefs is important for recovery, isolated reefs are more likely to have a slow recovery (Graham, Nash & Kool, 2011). Thirdly, the ecological characteristics of the reef,