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86-530: As a result of the proliferation of toxic algae or cyanobacteria , as well as nearby livestock farms, residential areas, large-scale deforestation, and land development, the lake is the most polluted in Paraguay. Due to the contamination, the lake has turned green and swimming in the lake is not advised. Ypacaraí Lake is located in the Salado River Basin, a low-elevation point. The area of the lake

172-433: A 2021 study on the cyanobacterium Synechocystis . These use a set of genes that regulate the production and export of sulphated polysaccharides , chains of sugar molecules modified with sulphate groups that can often be found in marine algae and animal tissue. Many bacteria generate extracellular polysaccharides, but sulphated ones have only been seen in cyanobacteria. In Synechocystis these sulphated polysaccharide help

258-523: A color name in English was in 1879. Further origins of the color name can be traced back to a dye produced from the cornflower ( Centaurea cyanus ). In most languages, 'cyan' is not a basic color term and it phenomenologically appears as a greenish vibrant hue of blue to most English speakers. Other English terms for this "borderline" hue region include blue green , aqua , turquoise , teal , and grue . The web color cyan shown at right

344-417: A cyanobacterial species that does so is Microcoleus vaginatus . M. vaginatus stabilizes soil using a polysaccharide sheath that binds to sand particles and absorbs water. M. vaginatus also makes a significant contribution to the cohesion of biological soil crust . Some of these organisms contribute significantly to global ecology and the oxygen cycle . The tiny marine cyanobacterium Prochlorococcus

430-458: A fact that may be responsible for their evolutionary and ecological success. The water-oxidizing photosynthesis is accomplished by coupling the activity of photosystem (PS) II and I ( Z-scheme ). In contrast to green sulfur bacteria which only use one photosystem, the use of water as an electron donor is energetically demanding, requiring two photosystems. Attached to the thylakoid membrane, phycobilisomes act as light-harvesting antennae for

516-658: A fair where local artists exhibit their work. Visitors and tourists can obtain information at the cultural center Estacion A; there is also an art center, the Guaggari Center, which is located at the entrance to the city and includes a sculpture exhibition. La Casa de la Cultura is a historical museum where temporary exhibitions are also presented. It opens for the Ypacaraí Festival that takes place in September. Ypacaraí Festival has been held every year in

602-429: A highly regarded precious gem. Turquoise comes in a variety of shades from green to blue, but cyan hues are particularly prevalent. Approximately 3,700 years ago, an intricately crafted dragon-shaped treasure made from over 2,000 pieces of turquoise and jade was created. This artifact is widely recognized as the oldest Chinese dragon totem by many Chinese scholars. Turquoise jewelry also held significant importance among

688-411: A key role in developmental processes, such as akinete and heterocyst differentiation, as well as strategy for population survival. Cyanophages are viruses that infect cyanobacteria. Cyanophages can be found in both freshwater and marine environments. Marine and freshwater cyanophages have icosahedral heads, which contain double-stranded DNA, attached to a tail by connector proteins. The size of

774-494: A printed page. To reproduce the web color cyan in inks, it is necessary to add some white ink to the printer's cyan below, so when it is reproduced in printing, it is not a primary subtractive color. It is called aqua (a name in use since 1598) because it is a color commonly associated with water , such as the appearance of the water at a tropical beach. Cyan is also one of the common inks used in four-color printing , along with magenta , yellow , and black ; this set of colors

860-552: A process where the energy of light is used to synthesize organic compounds from carbon dioxide. Because they are aquatic organisms, they typically employ several strategies which are collectively known as a "CO 2 concentrating mechanism" to aid in the acquisition of inorganic carbon (CO 2 or bicarbonate ). Among the more specific strategies is the widespread prevalence of the bacterial microcompartments known as carboxysomes , which co-operate with active transporters of CO 2 and bicarbonate, in order to accumulate bicarbonate into

946-442: A proposed model of microbial distribution, spatial organization, carbon and O 2 cycling in clumps and adjacent areas. (a) Clumps contain denser cyanobacterial filaments and heterotrophic microbes. The initial differences in density depend on cyanobacterial motility and can be established over short timescales. Darker blue color outside of the clump indicates higher oxygen concentrations in areas adjacent to clumps. Oxic media increase

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1032-412: A range of toxins known as cyanotoxins that can cause harmful health effects in humans and animals. Cyanobacteria are a very large and diverse phylum of photosynthetic prokaryotes . They are defined by their unique combination of pigments and their ability to perform oxygenic photosynthesis . They often live in colonial aggregates that can take on a multitude of forms. Of particular interest are

1118-559: A response to biotic and abiotic stresses. However, cell death research in cyanobacteria is a relatively young field and understanding of the underlying mechanisms and molecular machinery underpinning this fundamental process remains largely elusive. However, reports on cell death of marine and freshwater cyanobacteria indicate this process has major implications for the ecology of microbial communities/ Different forms of cell demise have been observed in cyanobacteria under several stressful conditions, and cell death has been suggested to play

1204-492: A serious threat to aquatic environments and public health, and are increasing in frequency and magnitude globally. Cyanobacteria are ubiquitous in marine environments and play important roles as primary producers . They are part of the marine phytoplankton , which currently contributes almost half of the Earth's total primary production. About 25% of the global marine primary production is contributed by cyanobacteria. Within

1290-500: A symbiotic relationship with plants or lichen -forming fungi (as in the lichen genus Peltigera ). Cyanobacteria are globally widespread photosynthetic prokaryotes and are major contributors to global biogeochemical cycles . They are the only oxygenic photosynthetic prokaryotes, and prosper in diverse and extreme habitats. They are among the oldest organisms on Earth with fossil records dating back at least 2.1 billion years. Since then, cyanobacteria have been essential players in

1376-457: A tint being a cyan mixed with white, and a shade being mixed with black. Color nomenclature is subjective. Many shades of cyan with a bluish hue are called blue. Similarly, those with a greenish hue are referred to as green. A cyan with a dark shade is commonly known as teal . A teal blue shade leans toward the blue end of the spectrum. Variations of teal with a greener tint are commonly referred to as teal green . Turquoise , reminiscent of

1462-419: A waving motion; the filament oscillates back and forth. In water columns, some cyanobacteria float by forming gas vesicles , as in archaea . These vesicles are not organelles as such. They are not bounded by lipid membranes , but by a protein sheath. Some cyanobacteria can fix atmospheric nitrogen in anaerobic conditions by means of specialized cells called heterocysts . Heterocysts may also form under

1548-408: A weaker cell in a filament, called a necridium. Some filamentous species can differentiate into several different cell types: Each individual cell (each single cyanobacterium) typically has a thick, gelatinous cell wall . They lack flagella , but hormogonia of some species can move about by gliding along surfaces. Many of the multicellular filamentous forms of Oscillatoria are capable of

1634-578: A wide range of cyanobacteria and are key regulators of the cyanobacterial populations in aquatic environments, and may aid in the prevention of cyanobacterial blooms in freshwater and marine ecosystems. These blooms can pose a danger to humans and other animals, particularly in eutrophic freshwater lakes. Infection by these viruses is highly prevalent in cells belonging to Synechococcus spp. in marine environments, where up to 5% of cells belonging to marine cyanobacterial cells have been reported to contain mature phage particles. The first cyanophage, LPP-1 ,

1720-618: Is 31 km (19 mi) from Asunción . It is a favorite place for writers and famous people. There is also a public beach. Areguá holds fairs throughout the year where local artisans sell pottery and other goods. The lake is visible when visiting one of the surrounding cities. Buses depart to San Bernardino and Ypacaraí from the Asunción Bus Terminal, and there is a bus to Areguá from Avenida San Martín or Aviadores del Chaco in Asunción. Cyanobacteria As of 2014

1806-561: Is a secondary color in the RGB color model , which uses combinations of red, green and blue light to create all the colors on computer and television displays. In X11 colors , this color is called both cyan and aqua . In the HTML color list, this same color is called aqua. The web colors are more vivid than the cyan used in the CMYK color system, and the web colors cannot be accurately reproduced on

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1892-417: Is a way for the cells to maximize the use of available light for photosynthesis. A few genera lack phycobilisomes and have chlorophyll b instead ( Prochloron , Prochlorococcus , Prochlorothrix ). These were originally grouped together as the prochlorophytes or chloroxybacteria, but appear to have developed in several different lines of cyanobacteria. For this reason, they are now considered as part of

1978-610: Is about 90 km (35 sq mi). It is 24 km (15 mi) long north-south and 6 km (3.7 mi) long east-west. The average depth of the water is roughly 1.72 metres (5.6 ft). The lake flows into the Salado River , which itself enters the Paraguay River and receives water from various bodies of water such as the Yagua Resau, Yuquyry, Puente Estrella, and Pirayu. The Salado River Basin, where

2064-445: Is also a history museum, a public library and classes in acting and dance. The lake is surrounded by cities with facilities for tourists and other visitors. Its beaches are open to the public. This city is 48 km (30 mi) from Asunción . It has beaches, cultural centers, pubs, and restaurants. San Bernardino is also called the “Summer City” because of its facilities and attractions for visitors during that season. Areguá

2150-728: Is favoured in ponds and lakes where waters are calm and have little turbulent mixing. Their lifecycles are disrupted when the water naturally or artificially mixes from churning currents caused by the flowing water of streams or the churning water of fountains. For this reason blooms of cyanobacteria seldom occur in rivers unless the water is flowing slowly. Growth is also favoured at higher temperatures which enable Microcystis species to outcompete diatoms and green algae , and potentially allow development of toxins. Based on environmental trends, models and observations suggest cyanobacteria will likely increase their dominance in aquatic environments. This can lead to serious consequences, particularly

2236-487: Is known regarding the nature (e.g., genetic diversity, host or cyanobiont specificity, and cyanobiont seasonality) of the symbiosis involved, particularly in relation to dinoflagellate host. Some cyanobacteria – even single-celled ones – show striking collective behaviours and form colonies (or blooms ) that can float on water and have important ecological roles. For instance, billions of years ago, communities of marine Paleoproterozoic cyanobacteria could have helped create

2322-485: Is later used to make amino acids and proteins. Marine picocyanobacteria ( Prochlorococcus and Synechococcus ) numerically dominate most phytoplankton assemblages in modern oceans, contributing importantly to primary productivity. While some planktonic cyanobacteria are unicellular and free living cells (e.g., Crocosphaera , Prochlorococcus , Synechococcus ); others have established symbiotic relationships with haptophyte algae , such as coccolithophores . Amongst

2408-419: Is possibly the most plentiful genus on Earth: a single millilitre of surface seawater can contain 100,000 cells of this genus or more. Worldwide there are estimated to be several octillion (10 , a billion billion billion) individuals. Prochlorococcus is ubiquitous between latitudes 40°N and 40°S, and dominates in the oligotrophic (nutrient-poor) regions of the oceans. The bacterium accounts for about 20% of

2494-461: Is referred to as CMYK. In printing, the cyan ink is sometimes known as printer's cyan, process cyan, or process blue. While both the additive secondary and the subtractive primary are called cyan , they can be substantially different from one another. Cyan printing ink is typically more saturated than the RGB secondary cyan, depending on what RGB color space and ink are considered. That is, process cyan

2580-438: Is the complement of red ; it can be made by the removal of red from white. Mixing red light and cyan light at the right intensity will make white light. Different shades of cyan can vary in terms of hue, chroma (also known as saturation, intensity, or colorfulness), or lightness (or value, tone, or brightness), or any combination of these characteristics. Differences in value can also be referred to as tints and shades, with

2666-506: Is usually outside the RGB gamut , and there is no fixed conversion from CMYK primaries to RGB. Different formulations are used for printer's ink, so there can be variations in the printed color that is pure cyan ink. This is because real-world subtractive (unlike additive) color mixing does not consistently produce the same result when mixing apparently identical colors, since the specific frequencies filtered out to produce that color affect how it interacts with other colors. Phthalocyanine blue

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2752-588: The Aztecs , who often featured this precious gemstone in vibrant frescoes for both symbolic and decorative purposes. The Aztecs revered turquoise, associating its color with the heavens and sacredness. Additionally, ancient Egyptians interpreted cyan hues as representing faith and truth, while Tibetans viewed them as a symbol of infinity. After earlier uses in various contexts, cyan hues found increased use in diverse cultures due to their appealing aesthetic qualities in religious structures and art pieces. For example,

2838-449: The biosphere as we know it by burying carbon compounds and allowing the initial build-up of oxygen in the atmosphere. On the other hand, toxic cyanobacterial blooms are an increasing issue for society, as their toxins can be harmful to animals. Extreme blooms can also deplete water of oxygen and reduce the penetration of sunlight and visibility, thereby compromising the feeding and mating behaviour of light-reliant species. As shown in

2924-486: The black band disease ). Cyanobacteria can be found in almost every terrestrial and aquatic habitat  – oceans , fresh water , damp soil, temporarily moistened rocks in deserts , bare rock and soil, and even Antarctic rocks. They can occur as planktonic cells or form phototrophic biofilms . They are found inside stones and shells (in endolithic ecosystems ). A few are endosymbionts in lichens , plants, various protists , or sponges and provide energy for

3010-629: The early Earth 's anoxic, weakly reducing prebiotic atmosphere , into an oxidizing one with free gaseous oxygen (which previously would have been immediately removed by various surface reductants ), resulting in the Great Oxidation Event and the " rusting of the Earth " during the early Proterozoic , dramatically changing the composition of life forms on Earth. The subsequent adaptation of early single-celled organisms to survive in oxygenous environments likely had led to endosymbiosis between anaerobes and aerobes , and hence

3096-448: The filamentous species , which often dominate the upper layers of microbial mats found in extreme environments such as hot springs , hypersaline water , deserts and the polar regions, but are also widely distributed in more mundane environments as well. They are evolutionarily optimized for environmental conditions of low oxygen. Some species are nitrogen-fixing and live in a wide variety of moist soils and water, either freely or in

3182-501: The host . Some live in the fur of sloths , providing a form of camouflage . Aquatic cyanobacteria are known for their extensive and highly visible blooms that can form in both freshwater and marine environments. The blooms can have the appearance of blue-green paint or scum. These blooms can be toxic , and frequently lead to the closure of recreational waters when spotted. Marine bacteriophages are significant parasites of unicellular marine cyanobacteria. Cyanobacterial growth

3268-464: The Earth's ecosystems. Planktonic cyanobacteria are a fundamental component of marine food webs and are major contributors to global carbon and nitrogen fluxes . Some cyanobacteria form harmful algal blooms causing the disruption of aquatic ecosystem services and intoxication of wildlife and humans by the production of powerful toxins ( cyanotoxins ) such as microcystins , saxitoxin , and cylindrospermopsin . Nowadays, cyanobacterial blooms pose

3354-602: The accumulation of particulate organic carbon (cells, sheaths and heterotrophic organisms) in clumps. It has been unclear why and how cyanobacteria form communities. Aggregation must divert resources away from the core business of making more cyanobacteria, as it generally involves the production of copious quantities of extracellular material. In addition, cells in the centre of dense aggregates can also suffer from both shading and shortage of nutrients. So, what advantage does this communal life bring for cyanobacteria? New insights into how cyanobacteria form blooms have come from

3440-490: The activities of ancient cyanobacteria. They are often found as symbionts with a number of other groups of organisms such as fungi (lichens), corals , pteridophytes ( Azolla ), angiosperms ( Gunnera ), etc. The carbon metabolism of cyanobacteria include the incomplete Krebs cycle , the pentose phosphate pathway , and glycolysis . There are some groups capable of heterotrophic growth, while others are parasitic , causing diseases in invertebrates or algae (e.g.,

3526-480: The appropriate environmental conditions (anoxic) when fixed nitrogen is scarce. Heterocyst-forming species are specialized for nitrogen fixation and are able to fix nitrogen gas into ammonia ( NH 3 ), nitrites ( NO − 2 ) or nitrates ( NO − 3 ), which can be absorbed by plants and converted to protein and nucleic acids (atmospheric nitrogen is not bioavailable to plants, except for those having endosymbiotic nitrogen-fixing bacteria , especially

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3612-448: The basis of cyanobacteria's informal common name , blue-green algae , although as prokaryotes they are not scientifically classified as algae . Cyanobacteria are probably the most numerous taxon to have ever existed on Earth and the first organisms known to have produced oxygen , having appeared in the middle Archean eon and apparently originated in a freshwater or terrestrial environment . Their photopigments can absorb

3698-540: The city of Ypacaraí since 1971. The September gathering hosts folk expression and Paraguayan art, including concerts, dance and theater. According to the City Chamber, the festival “tries to rescue and reinforce the artistic heritage of the Paraguayan culture”. Casa Hassler, a cultural center, is open for the whole year, with permanent and temporary exhibitions. Artists can show their work here for free, and there

3784-432: The clump from the overlying medium and is also produced within the clump by respiration. In oxic solutions, high O 2 concentrations reduce the efficiency of CO 2 fixation and result in the excretion of glycolate. Under these conditions, clumping can be beneficial to cyanobacteria if it stimulates the retention of carbon and the assimilation of inorganic carbon by cyanobacteria within clumps. This effect appears to promote

3870-741: The color of the stone. In the 1870s, the French sculptor Frédéric Bartholdi began the construction of what would later become the Statue of Liberty . Over time, exposure to the elements caused the copper structure to develop its distinctive patina , now recognized as iconic cyan. Following this, there was a significant advancement in the use of cyan during the late 19th and early 20th centuries. Impressionist artists, such as Claude Monet in his renowned Water Lilies , effectively incorporated cyan hues into their works. Deviating from traditional interpretations of local color under neutral lighting conditions,

3956-918: The contamination of sources of drinking water . Researchers including Linda Lawton at Robert Gordon University , have developed techniques to study these. Cyanobacteria can interfere with water treatment in various ways, primarily by plugging filters (often large beds of sand and similar media) and by producing cyanotoxins , which have the potential to cause serious illness if consumed. Consequences may also lie within fisheries and waste management practices. Anthropogenic eutrophication , rising temperatures, vertical stratification and increased atmospheric carbon dioxide are contributors to cyanobacteria increasing dominance of aquatic ecosystems. Cyanobacteria have been found to play an important role in terrestrial habitats and organism communities. It has been widely reported that cyanobacteria soil crusts help to stabilize soil to prevent erosion and retain water. An example of

4042-434: The cyanobacteria, only a few lineages colonized the open ocean: Crocosphaera and relatives, cyanobacterium UCYN-A , Trichodesmium , as well as Prochlorococcus and Synechococcus . From these lineages, nitrogen-fixing cyanobacteria are particularly important because they exert a control on primary productivity and the export of organic carbon to the deep ocean, by converting nitrogen gas into ammonium, which

4128-509: The cyanobacterial group. In general, photosynthesis in cyanobacteria uses water as an electron donor and produces oxygen as a byproduct, though some may also use hydrogen sulfide a process which occurs among other photosynthetic bacteria such as the purple sulfur bacteria . Carbon dioxide is reduced to form carbohydrates via the Calvin cycle . The large amounts of oxygen in the atmosphere are considered to have been first created by

4214-462: The cyanobacterium form buoyant aggregates by trapping oxygen bubbles in the slimy web of cells and polysaccharides. Previous studies on Synechocystis have shown type IV pili , which decorate the surface of cyanobacteria, also play a role in forming blooms. These retractable and adhesive protein fibres are important for motility, adhesion to substrates and DNA uptake. The formation of blooms may require both type IV pili and Synechan – for example,

4300-497: The cytoplasm of the cell. Carboxysomes are icosahedral structures composed of hexameric shell proteins that assemble into cage-like structures that can be several hundreds of nanometres in diameter. It is believed that these structures tether the CO 2 -fixing enzyme, RuBisCO , to the interior of the shell, as well as the enzyme carbonic anhydrase , using metabolic channeling to enhance the local CO 2 concentrations and thus increase

4386-432: The diagram on the right, bacteria can stay in suspension as individual cells, adhere collectively to surfaces to form biofilms, passively sediment, or flocculate to form suspended aggregates. Cyanobacteria are able to produce sulphated polysaccharides (yellow haze surrounding clumps of cells) that enable them to form floating aggregates. In 2021, Maeda et al. discovered that oxygen produced by cyanobacteria becomes trapped in

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4472-464: The efficiency of the RuBisCO enzyme. In contrast to purple bacteria and other bacteria performing anoxygenic photosynthesis , thylakoid membranes of cyanobacteria are not continuous with the plasma membrane but are separate compartments. The photosynthetic machinery is embedded in the thylakoid membranes, with phycobilisomes acting as light-harvesting antennae attached to the membrane, giving

4558-930: The evolution of eukaryotes during the Paleoproterozoic . Cyanobacteria use photosynthetic pigments such as various forms of chlorophyll , carotenoids , phycobilins to convert the photonic energy in sunlight to chemical energy . Unlike heterotrophic prokaryotes, cyanobacteria have internal membranes . These are flattened sacs called thylakoids where photosynthesis is performed. Photoautotrophic eukaryotes such as red algae , green algae and plants perform photosynthesis in chlorophyllic organelles that are thought to have their ancestry in cyanobacteria, acquired long ago via endosymbiosis. These endosymbiont cyanobacteria in eukaryotes then evolved and differentiated into specialized organelles such as chloroplasts , chromoplasts , etioplasts , and leucoplasts , collectively known as plastids . Sericytochromatia,

4644-443: The family Fabaceae , among others). Free-living cyanobacteria are present in the water of rice paddies , and cyanobacteria can be found growing as epiphytes on the surfaces of the green alga, Chara , where they may fix nitrogen. Cyanobacteria such as Anabaena (a symbiont of the aquatic fern Azolla ) can provide rice plantations with biofertilizer . Cyanobacteria use the energy of sunlight to drive photosynthesis ,

4730-477: The filamentous forms, Trichodesmium are free-living and form aggregates. However, filamentous heterocyst-forming cyanobacteria (e.g., Richelia , Calothrix ) are found in association with diatoms such as Hemiaulus , Rhizosolenia and Chaetoceros . Marine cyanobacteria include the smallest known photosynthetic organisms. The smallest of all, Prochlorococcus , is just 0.5 to 0.8 micrometres across. In terms of numbers of individuals, Prochlorococcus

4816-408: The first signs of multicellularity. Many cyanobacteria form motile filaments of cells, called hormogonia , that travel away from the main biomass to bud and form new colonies elsewhere. The cells in a hormogonium are often thinner than in the vegetative state, and the cells on either end of the motile chain may be tapered. To break away from the parent colony, a hormogonium often must tear apart

4902-413: The focus of artists was on accurately depicting perceived color and the influence of light on altering object hues. Specifically, daylight plays a significant role in shifting the perceived color of objects toward cyan hues. In 1917, the color term teal was introduced to describe deeper shades of cyan. In the late 19th century, while traditional nomenclature of red , yellow , and blue persisted,

4988-481: The green pigmentation observed (with wavelengths from 450 nm to 660 nm) in most cyanobacteria. While most of the high-energy electrons derived from water are used by the cyanobacterial cells for their own needs, a fraction of these electrons may be donated to the external environment via electrogenic activity. Respiration in cyanobacteria can occur in the thylakoid membrane alongside photosynthesis, with their photosynthetic electron transport sharing

5074-417: The head and tail vary among species of cyanophages. Cyanophages, like other bacteriophages , rely on Brownian motion to collide with bacteria, and then use receptor binding proteins to recognize cell surface proteins, which leads to adherence. Viruses with contractile tails then rely on receptors found on their tails to recognize highly conserved proteins on the surface of the host cell. Cyanophages infect

5160-514: The hues evolved, the printing industry maintained the use of the traditional terms red , yellow , and blue . Consequently, pinpointing the exact date of origin for CMYK , in which cyan serves as a primary color, proves challenging . In August 1991, the HP Deskwriter 500C became the first Deskwriter to offer color printing as an option. It used interchangeable black and color (cyan, magenta, and yellow) inkjet print cartridges. With

5246-501: The inclusion of cyan ink in printers, the term "cyan" has become widely recognized in both home and office settings. According to TUP/Technology User Profile 2020, approximately 70% of online American adults regularly use a home printer. Its name is derived from the Ancient Greek word kyanos (κύανος), meaning "dark blue enamel, Lapis lazuli ". It was formerly known as "cyan blue" or cyan-blue, and its first recorded use as

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5332-403: The lake is located, has a humid subtropical climate. The weather at the lake is mainly warm and sunny days are frequent. Temperature varies between 20 and 38 °C (68 and 100 °F) during the summer and 3 to 25 °C (37 to 77 °F) during the winter. The lake's original name was Tapycua. There are several possible explanations for the name. Ypacaraí means " holy lake " and is linked to

5418-408: The legend of the blessing of the lake by Luis de Bolaños around 1600. Lake Ypacarai is internationally known because of the song “Recuerdos de Ypacarai” ("Memories of Ypacarai") written by Demetrio Ortiz . The song has been performed and recorded by many singers, including Julio Iglesias. The nearby town of Areguá offers permanent art and crafts exhibitions. The artisan center of La Cuenca hosts

5504-544: The most abundant photosynthetic organisms on Earth, accounting for a quarter of all carbon fixed in marine ecosystems. In contrast to free-living marine cyanobacteria, some cyanobionts are known to be responsible for nitrogen fixation rather than carbon fixation in the host. However, the physiological functions of most cyanobionts remain unknown. Cyanobionts have been found in numerous protist groups, including dinoflagellates , tintinnids , radiolarians , amoebae , diatoms , and haptophytes . Among these cyanobionts, little

5590-453: The most extreme niches such as hot springs, salt works, and hypersaline bays. Photoautotrophic , oxygen-producing cyanobacteria created the conditions in the planet's early atmosphere that directed the evolution of aerobic metabolism and eukaryotic photosynthesis. Cyanobacteria fulfill vital ecological functions in the world's oceans, being important contributors to global carbon and nitrogen budgets." – Stewart and Falconer Some cyanobacteria,

5676-406: The network of polysaccharides and cells, enabling the microorganisms to form buoyant blooms. It is thought that specific protein fibres known as pili (represented as lines radiating from the cells) may act as an additional way to link cells to each other or onto surfaces. Some cyanobacteria also use sophisticated intracellular gas vesicles as floatation aids. The diagram on the left above shows

5762-418: The oxygen in the Earth's atmosphere. Cyanobacteria are variable in morphology, ranging from unicellular and filamentous to colonial forms . Filamentous forms exhibit functional cell differentiation such as heterocysts (for nitrogen fixation), akinetes (resting stage cells), and hormogonia (reproductive, motile filaments). These, together with the intercellular connections they possess, are considered

5848-716: The photosystems. The phycobilisome components ( phycobiliproteins ) are responsible for the blue-green pigmentation of most cyanobacteria. The variations on this theme are due mainly to carotenoids and phycoerythrins that give the cells their red-brownish coloration. In some cyanobacteria, the color of light influences the composition of the phycobilisomes. In green light, the cells accumulate more phycoerythrin, which absorbs green light, whereas in red light they produce more phycocyanin which absorbs red. Thus, these bacteria can change from brick-red to bright blue-green depending on whether they are exposed to green light or to red light. This process of "complementary chromatic adaptation"

5934-443: The pili may allow cyanobacteria from the same species to recognise each other and make initial contacts, which are then stabilised by building a mass of extracellular polysaccharide. The bubble flotation mechanism identified by Maeda et al. joins a range of known strategies that enable cyanobacteria to control their buoyancy, such as using gas vesicles or accumulating carbohydrate ballasts. Type IV pili on their own could also control

6020-413: The pili may help to export the polysaccharide outside the cell. Indeed, the activity of these protein fibres may be connected to the production of extracellular polysaccharides in filamentous cyanobacteria. A more obvious answer would be that pili help to build the aggregates by binding the cells with each other or with the extracellular polysaccharide. As with other kinds of bacteria, certain components of

6106-481: The position of marine cyanobacteria in the water column by regulating viscous drag. Extracellular polysaccharide appears to be a multipurpose asset for cyanobacteria, from floatation device to food storage, defence mechanism and mobility aid. One of the most critical processes determining cyanobacterial eco-physiology is cellular death . Evidence supports the existence of controlled cellular demise in cyanobacteria, and various forms of cell death have been described as

6192-496: The printing industry initiated a shift towards utilizing magenta and cyan inks for red and blue hues, respectively. This transition aimed to establish a more versatile color gamut achievable with only three primary colors. In 1949, a document in the printing industry stated: “The four-color set comprises Yellow , Red (magenta) , Blue (cyan) , Black ”. This practice of labeling magenta , yellow , and cyan as red , yellow , and blue persisted until 1961. As

6278-572: The prominent dome of the Goharshad Mosque in Iran , built in 1418, showcases this trend. Additionally, Jacopo da Pontormo's use of a teal shade for Mary's robe in the 1528 painting Carmignano Visitation demonstrates the allure for these hues. During the 16th century, speakers of the English language began using the term turquoise to describe the cyan color of objects that resembled

6364-478: The proposed name of the paraphyletic and most basal group, is the ancestor of both the non-photosynthetic group Melainabacteria and the photosynthetic cyanobacteria, also called Oxyphotobacteria. The cyanobacteria Synechocystis and Cyanothece are important model organisms with potential applications in biotechnology for bioethanol production, food colorings, as a source of human and animal food, dietary supplements and raw materials. Cyanobacteria produce

6450-468: The red- and blue-spectrum frequencies of sunlight (thus reflecting a greenish color) to split water molecules into hydrogen ions and oxygen. The hydrogen ions are used to react with carbon dioxide to produce complex organic compounds such as carbohydrates (a process known as carbon fixation ), and the oxygen is released as a byproduct . By continuously producing and releasing oxygen over billions of years, cyanobacteria are thought to have converted

6536-427: The reversal frequencies of any filaments that begin to leave the clumps, thereby reducing the net migration away from the clump. This enables the persistence of the initial clumps over short timescales; (b) Spatial coupling between photosynthesis and respiration in clumps. Oxygen produced by cyanobacteria diffuses into the overlying medium or is used for aerobic respiration. Dissolved inorganic carbon (DIC) diffuses into

6622-448: The root surface within a restricted zone by Nostoc . The relationships between cyanobionts (cyanobacterial symbionts) and protistan hosts are particularly noteworthy, as some nitrogen-fixing cyanobacteria ( diazotrophs ) play an important role in primary production , especially in nitrogen-limited oligotrophic oceans. Cyanobacteria, mostly pico-sized Synechococcus and Prochlorococcus , are ubiquitously distributed and are

6708-514: The roots of wheat and cotton plants. Calothrix sp. has also been found on the root system of wheat. Monocots , such as wheat and rice, have been colonised by Nostoc spp., In 1991, Ganther and others isolated diverse heterocystous nitrogen-fixing cyanobacteria, including Nostoc , Anabaena and Cylindrospermum , from plant root and soil. Assessment of wheat seedling roots revealed two types of association patterns: loose colonization of root hair by Anabaena and tight colonization of

6794-415: The same compartment as the components of respiratory electron transport. While the goal of photosynthesis is to store energy by building carbohydrates from CO 2 , respiration is the reverse of this, with carbohydrates turned back into CO 2 accompanying energy release. Cyanobacteria appear to separate these two processes with their plasma membrane containing only components of the respiratory chain, while

6880-429: The so-called cyanobionts (cyanobacterial symbionts), have a symbiotic relationship with other organisms, both unicellular and multicellular. As illustrated on the right, there are many examples of cyanobacteria interacting symbiotically with land plants . Cyanobacteria can enter the plant through the stomata and colonize the intercellular space, forming loops and intracellular coils. Anabaena spp. colonize

6966-434: The stone with the same name, is a shade in the green spectrum of cyan hues. Celeste is a lightly tinted cyan that represents the color of a clear sky. Other colors in the cyan color range are electric blue , aquamarine , and others described as blue-green . Cyan boasts a rich and diverse history, holding cultural significance for millennia. In ancient civilizations, turquoise , valued for its aesthetic appeal, served as

7052-440: The taxonomy was under revision Cyanobacteria ( / s aɪ ˌ æ n oʊ b æ k ˈ t ɪər i . ə / ), also called Cyanobacteriota or Cyanophyta , are a phylum of autotrophic gram-negative bacteria that can obtain biological energy via oxygenic photosynthesis . The name "cyanobacteria" (from Ancient Greek κύανος ( kúanos )  'blue') refers to their bluish green ( cyan ) color, which forms

7138-473: The thylakoid membrane hosts an interlinked respiratory and photosynthetic electron transport chain. Cyanobacteria use electrons from succinate dehydrogenase rather than from NADPH for respiration. Cyanobacteria only respire during the night (or in the dark) because the facilities used for electron transport are used in reverse for photosynthesis while in the light. Many cyanobacteria are able to reduce nitrogen and carbon dioxide under aerobic conditions,

7224-434: The wavelengths of green and blue. In the subtractive color system, or CMYK color model , which can be overlaid to produce all colors in paint and color printing, cyan is one of the primary colors , along with magenta and yellow . In the additive color system, or RGB color model , used to create all the colors on a computer or television display, cyan is made by mixing equal amounts of green and blue light . Cyan

7310-421: Was discovered in 1963. Cyanophages are classified within the bacteriophage families Myoviridae (e.g. AS-1 , N-1 ), Podoviridae (e.g. LPP-1) and Siphoviridae (e.g. S-1 ). Cyan Cyan ( / ˈ s aɪ . ə n , - æ n / ) is the color between blue and green on the visible spectrum of light . It is evoked by light with a predominant wavelength between 500 and 520 nm , between

7396-500: Was discovered in 1986 and accounts for more than half of the photosynthesis of the open ocean. Circadian rhythms were once thought to only exist in eukaryotic cells but many cyanobacteria display a bacterial circadian rhythm . "Cyanobacteria are arguably the most successful group of microorganisms on earth. They are the most genetically diverse; they occupy a broad range of habitats across all latitudes, widespread in freshwater, marine, and terrestrial ecosystems, and they are found in

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