Chlorophyll C is found in red algae, brown algae, and dinoflagellates This has lead to their classification under the Kingdom Chromista 4. Chlorophyll D is a minor pigment found in some red algae, while the rare Chlorophyll E has been found in yellow-green algae.
Chlorophyll F was recently discovered in some cyanobacteria near Australia Each of these accessory pigments will strongly absorb different wavelengths, so their presence makes photosynthesis more efficient Chlorophyll is not the only photosynthetic pigment found in algae and phytoplankton.
There are also carotenoids,and phycobilins biliproteins. These accessory pigments are responsible for other organism colors, such as yellow, red, blue and brown. Like chlorophylls B, C, D, E and F, these molecules improve light energy absorption, but they are not a primary part of photosynthesis. There are two phycobilins found in phytoplankton: phycoerythrin and phycocyanin. Phycoerythrin reflects red light, and can be found in red algae and cyanobacteria.
Some algae will appear green despite the presence of these accessory pigments. Just as in plants, the chlorophyll in algae has a stronger relative absorption than the other molecules. Like a dominant trait, the more intense, reflected green wavelengths can mask the other, less-reflected colors In green algae, chlorophyll is also found at a higher concentration relative to the accessory pigments.
When the accessory pigments are more concentrated such as in red algae, brown algae and cyanobacteria , the other colors can be seen Photosynthesis is the process by which organisms use sunlight to produce sugars for energy.
Plants, algae and cyanobacteria all conduct oxygenic photosynthesis 1, That means they require carbon dioxide, water, and sunlight solar energy is collected by chlorophyll A. Plants and phytoplankton use these three ingredients to produce glucose sugar and oxygen. This sugar is used in the metabolic processes of the organism, and the oxygen, produced as a byproduct, is essential to nearly all other life, underwater and on land 1, Phytoplankton drifting about below the surface of the water still carry out photosynthesis.
This process can occur as long as enough light is available for the chlorophyll and other pigments to absorb. In the ocean, light can reach as far as m below the surface This region where sunlight can reach is known as the euphotic zone. Phytoplankton and other algae can be found throughout this zone. As light is required for photosynthesis to occur, the amount of light available will affect this process.
Photosynthetic production peaks during the day and declines after dark However, not all light can be used for photosynthesis. Only the visible light range blue to red is considered photosynthetically active radiation 1. Ultraviolet light has too much energy for photosynthesis, and infrared light does not have enough. Within the visible light spectrum, chlorophyll strongly absorbs red and blue light while reflecting green light This is why phytoplankton, particularly cyanobacteria, can thrive at the bottom of the euphotic sunlit zone, where only blue light can reach.
As blue light is both high in energy and strongly absorbed by chlorophyll, it can be used effectively in photosynthesis. Turbidity, or the presence of suspended particles in the water, affects the amount of light that reaches into the water 1. The more sediment and other particles in the water, the less light will be able to penetrate.
With less light available, photosynthetic production will decrease. Water temperature will also affect photosynthesis rates 1. As a chemical reaction, photosynthesis is initiated and sped up by heat As photosynthesis production increases, so will phytoplankton reproduction rates This factors into the large, seasonal swings of phytoplankton populations However, the extent to which temperature affects photosynthesis in algae and cyanobacteria is dependent on the species. For all phytoplankton, photosynthetic production will increase with the temperature, though each organism has a slightly different optimum temperature range 1.
When this optimum temperature is exceeded, photosynthetic activity will in turn be reduced. Too much heat will denature break down the enzymes used during the process, slowing down photosynthesis instead of speeding it up Microscopic phytoplankton play some of the biggest roles in climate control, oxygen supply and food production.
That process uses up carbon dioxide, which helps regulate CO2 levels in the atmosphere, and produces oxygen for other organisms to live Phytoplankton make up the foundation of the oceanic food web. A food web is a complex net of organisms and food chains who-eats-who. To survive, every living thing needs organic carbon Phytoplankton produce their required sugar through photosynthesis.
As they are able to produce their own energy with the help of light, they are considered autotrophic self-feeding. Phytoplankton and other autotrophs are called primary producers, and make up the bottom of the food web Phytoplankton are generally consumed by zooplankton and small marine organisms like krill.
These creatures are then consumed by larger marine organisms, such as fish 29, This chain continues up to apex predators, including sharks, polar bears and humans. During the photosynthetic process, phytoplankton produce oxygen as a byproduct.
Due to their vast and widespread populations, algae and cyanobacteria are responsible for approximately half of all the oxygen found in the ocean and in our atmosphere Thus oceanic lifeforms not only feed off the phytoplankton, but also require the dissolved oxygen they produce to live.
Before plants, algae and phytoplankton used water for photosynthesis, bacteria used H2S and other organic compounds to fix CO2 Early cyanobacteria were the first organism to use water to fix carbon The use of H2O introduced free oxygen O2 into the environment as a byproduct. This process slowly changed the inert Precambrian atmosphere into the oxygen-rich environment known today In addition to providing food and oxygen for nearly all life on Earth, phytoplankton help to regulate inorganic carbon carbon dioxide in the atmosphere During photosynthesis, carbon dioxide and water molecules are used to make sugar for energy.
The process of incorporating inorganic carbon into organic carbon glucose and other biologically useful compounds is called carbon fixation, and is part of the biological carbon pump Phytoplankton consume a similar amount of carbon dioxide as all land plants combined While phytoplankton can pull carbon dioxide from the atmosphere or the ocean, it will have a similar effect. This consumption helps keep carbon dioxide levels in check, reducing its presence as a greenhouse gas If the phytoplankton is not eaten by another organism passing on the carbon up the food chain , then it will sink into the ocean when it dies.
As with other detritus non-living organic material , the phytoplankton will be decomposed by bacteria, and the carbon is either released back into the ocean as dissolved carbon dioxide or eventually deposited into the seafloor sediment Thanks to phytoplankton, this biological carbon pump removes approximately 10 trillion kilograms 10 gigatonnes of carbon from the atmosphere every year, transferring it to the ocean depths In climate terms, this process helps to maintain global surface temperatures Without this cycle, atmospheric CO2 would rise approximately ppm current levels are around ppm 33, Even small changes in phytoplankton populations could have an effect on the atmosphere and world climate Phytoplankton populations and their subsequent photosynthetic productivity will fluctuate due to a number of factors, most of which are part of seasonal changes The largest influence on phytoplankton levels is nutrient scarcity While sunlight levels affect productivity, nutrient levels affect phytoplankton growth and populations.
While any one phytoplankton only lives for a few days, a population boom can last for weeks under the right conditions As phytoplankton populations grow and shrink seasonally, typical concentrations vary not only by location but from month to month Expected levels should be based on local, seasonal data from previous years. While changes within the same calendar year are normal, populations should stay consistent with previous seasonal fluctuations from year to year.
If phytoplankton concentrations are abnormally high or low for a season, it may indicate other water quality concerns that should be addressed. Phytoplankton require sunlight for photosynthesis.
If sunlight is limited, phytoplankton productivity will decrease. This can be seen in a daily cycle as oxygen levels fluctuate with light levels throughout the day. However, if sunlight is unavailable or minimal for an extended period of time, aquatic life will consume dissolved oxygen quicker than phytoplankton can restore it, leading to a plummet in dissolved oxygen levels 1.
Phytoplankton are responsible for much of the dissolved oxygen found in surface waters As oxygen is required for fish and other aquatic organisms, a decrease in photosynthesis productivity is detrimental to aquatic populations.
Without phytoplankton, the oxygen supply of the ocean would be cut in half. In both fresh and saltwater, a lengthy decrease in phytoplanktonic productivity can lead to a fish kill massive fish die-off 1. Although phytoplankton require sunlight for photosynthesis and oxygen production, too much light can be harmful to photosynthetic production.
On very bright days, UV-B radiation can diminish photosynthesis by 8. This is why photosynthesis rates peak during the morning, and decrease at noon when the radiation levels are highest 1. Additionally, Blue-Green Algae can cause serious health problems in pets and humans exposed to it. When in doubt, stay out! There has been some concern about increasing algal growth in North Shore streams.
Check out this report for a qualitative assessment on increasing periphyton in some local streams. Anyone who has ever tried to walk across a stream knows that the rocks under the water are slippery. If you were to scrape a bit of that slime off and put it on a glass slide, and look at it under a microscope, you would see a community of diatoms, blue-green, and green algae, single-celled animals, bacteria, fungi and lots of organic matter.
This is what makes the rocks slippery. It so happens that these plants are the favorite food of many of the stream's herbivores! The MPCA streams and lakes and MN DNR have information about algae including the potentially toxic species in lakes that have been in the media lately; what's natural and what isn't; and how they can be managed if necessary and allowable.
Algal blooms may occur in freshwater as well as marine environments. Algal bloom concentrations may reach millions of cells per milliliter. Colors observed are green, yellowish-brown, or red. Bright green blooms may also occur. These are a result of blue-green algae, which are actually bacteria cyanobacteria. As more algae and plants grow, others die. This dead organic matter becomes food for bacteria that decompose it. When the dissolved oxygen content decreases, many fish and aquatic insects cannot survive.
This results in a dead area. Algal blooms may also be of concern as some species of algae produce neurotoxins. Related Stories. They also make the news occasionally for poisoning fish, people and other animals. What's less frequently Apparently, bacteria act accordingly.
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