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Rhodophyte
Red algae, or Rhodophyta (, ; ), are one of the oldest groups of eukaryotic algae. The Rhodophyta also comprises one of the largest phyla of algae, containing over 7,000 currently recognized species with taxonomic revisions ongoing. The majority of species (6,793) are found in the Florideophyceae (class), and mostly consist of multicellular, marine algae, including many notable seaweeds. Red algae are abundant in marine habitats but relatively rare in freshwaters. Approximately 5% of red algae species occur in freshwater environments, with greater concentrations found in warmer areas. Except for two coastal cave dwelling species in the asexual class Cyanidiophyceae, there are no terrestrial species, which may be due to an evolutionary bottleneck in which the last common ancestor lost about 25% of its core genes and much of its evolutionary plasticity. The red algae form a distinct group characterized by having eukaryotic cells without flagella and centrioles, chloroplasts that lac ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Chloroplast
A chloroplast () is a type of membrane-bound organelle known as a plastid that conducts photosynthesis mostly in plant and algal cells. The photosynthetic pigment chlorophyll captures the energy from sunlight, converts it, and stores it in the energy-storage molecules ATP and NADPH while freeing oxygen from water in the cells. The ATP and NADPH is then used to make organic molecules from carbon dioxide in a process known as the Calvin cycle. Chloroplasts carry out a number of other functions, including fatty acid synthesis, amino acid synthesis, and the immune response in plants. The number of chloroplasts per cell varies from one, in unicellular algae, up to 100 in plants like ''Arabidopsis'' and wheat. A chloroplast is characterized by its two membranes and a high concentration of chlorophyll. Other plastid types, such as the leucoplast and the chromoplast, contain little chlorophyll and do not carry out photosynthesis. Chloroplasts are highly dynamic—they circulat ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Floridean Starch
Floridean starch is a type of a storage glucan found in glaucophytes and in red algae (or rhodophytes), in which it is usually the primary sink for fixed carbon from photosynthesis. It is found in grains or granules in the cell's cytoplasm and is composed of an α-linked glucose polymer with a degree of branching intermediate between amylopectin and glycogen, though more similar to the former. The polymers that make up floridean starch are sometimes referred to as "semi-amylopectin". Properties Floridean starch consists of a polymer of glucose molecules connected primarily by α(1,4) linkages, with occasional branch points using α(1,6) linkages. It differs from other common α-linked glucose polymers in the frequency and position of the branches, which gives rise to different physical properties. The structure of floridean starch polymers is most similar to amylopectin and is sometimes described as "semi-amylopectin". Floridean starch is often described in contrast to starch (a mi ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Eurhodophytina
Red algae, or Rhodophyta (, ; ), are one of the oldest groups of eukaryotic algae. The Rhodophyta also comprises one of the largest phyla of algae, containing over 7,000 currently recognized species with taxonomic revisions ongoing. The majority of species (6,793) are found in the Florideophyceae (class), and mostly consist of multicellular, marine algae, including many notable seaweeds. Red algae are abundant in marine habitats but relatively rare in freshwaters. Approximately 5% of red algae species occur in freshwater environments, with greater concentrations found in warmer areas. Except for two coastal cave dwelling species in the asexual class Cyanidiophyceae, there are no terrestrial species, which may be due to an evolutionary bottleneck in which the last common ancestor lost about 25% of its core genes and much of its evolutionary plasticity. The red algae form a distinct group characterized by having eukaryotic cells without flagella and centrioles, chloroplasts that la ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Algae
Algae (; singular alga ) is an informal term for a large and diverse group of photosynthetic eukaryotic organisms. It is a polyphyletic grouping that includes species from multiple distinct clades. Included organisms range from unicellular microalgae, such as ''Chlorella,'' ''Prototheca'' and the diatoms, to multicellular forms, such as the giant kelp, a large brown alga which may grow up to in length. Most are aquatic and autotrophic (they generate food internally) and lack many of the distinct cell and tissue types, such as stomata, xylem and phloem that are found in land plants. The largest and most complex marine algae are called seaweeds, while the most complex freshwater forms are the ''Charophyta'', a division of green algae which includes, for example, ''Spirogyra'' and stoneworts. No definition of algae is generally accepted. One definition is that algae "have chlorophyll ''a'' as their primary photosynthetic pigment and lack a sterile covering of cells around thei ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Phycobiliprotein
Phycobiliproteins are water-soluble proteins present in cyanobacteria and certain algae (rhodophytes, cryptomonads, glaucocystophytes). They capture light energy, which is then passed on to chlorophylls during photosynthesis. Phycobiliproteins are formed of a complex between proteins and covalently bound phycobilins that act as chromophores (the light-capturing part). They are most important constituents of the phycobilisomes. Major phycobiliproteins Characteristics Phycobiliproteins demonstrate superior fluorescent properties compared to small organic fluorophores, especially when high sensitivity or multicolor detection required : * Broad and high absorption of light suits many light sources * Very intense emission of light: 10-20 times brighter than small organic fluorophores * Relative large Stokes shift gives low background, and allows multicolor detections. * Excitation and emission spectra do not overlap compared to conventional organic dyes. * Can be used in tandem ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Eukaryotic
Eukaryotes () are organisms whose cells have a nucleus. All animals, plants, fungi, and many unicellular organisms, are Eukaryotes. They belong to the group of organisms Eukaryota or Eukarya, which is one of the three domains of life. Bacteria and Archaea (both prokaryotes) make up the other two domains. The eukaryotes are usually now regarded as having emerged in the Archaea or as a sister of the Asgard archaea. This implies that there are only two domains of life, Bacteria and Archaea, with eukaryotes incorporated among archaea. Eukaryotes represent a small minority of the number of organisms, but, due to their generally much larger size, their collective global biomass is estimated to be about equal to that of prokaryotes. Eukaryotes emerged approximately 2.3–1.8 billion years ago, during the Proterozoic eon, likely as flagellated phagotrophs. Their name comes from the Greek εὖ (''eu'', "well" or "good") and κάρυον (''karyon'', "nut" or "kernel"). Euka ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Richard Wettstein
__NOTOC__ Richard Wettstein (30 June 1863 in Vienna – 10 August 1931 in Trins) was an Austrian botanist. His taxonomic system, the Wettstein system, was one of the earliest based on phyletic principles. Wettstein studied in Vienna, where he was a disciple of Anton Kerner von Marilaun (1831-1898) and married his daughter Adele. He was a professor at the University of Prague from 1892, and at the University of Vienna from 1899. He newly laid out the Botanical Garden of the University of Vienna. In 1901 he became president of the Vienna Zoological-Botanical Society (''Zoologisch-Botanische Gesellschaft''), and during the same year took part in a scientific expedition to Brazil. In 1919 he was appointed vice-president of the Vienna Academy of Sciences. During his later years (1929–30), he traveled with his son, Friedrich, to eastern and southern Africa. The mycological genus ''Wettsteinina'' is named in his honor and also '' Wettsteiniola'', which is a genus of flowering plants ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Ocean
The ocean (also the sea or the world ocean) is the body of salt water that covers approximately 70.8% of the surface of Earth and contains 97% of Earth's water. An ocean can also refer to any of the large bodies of water into which the world ocean is conventionally divided."Ocean." ''Merriam-Webster.com Dictionary'', Merriam-Webster, [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Cambridge University Press
Cambridge University Press is the university press of the University of Cambridge. Granted letters patent by Henry VIII of England, King Henry VIII in 1534, it is the oldest university press A university press is an academic publishing house specializing in monographs and scholarly journals. Most are nonprofit organizations and an integral component of a large research university. They publish work that has been reviewed by schola ... in the world. It is also the King's Printer. Cambridge University Press is a department of the University of Cambridge and is both an academic and educational publisher. It became part of Cambridge University Press & Assessment, following a merger with Cambridge Assessment in 2021. With a global sales presence, publishing hubs, and offices in more than 40 Country, countries, it publishes over 50,000 titles by authors from over 100 countries. Its publishing includes more than 380 academic journals, monographs, reference works, school and uni ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Accessory Pigment
Accessory pigments are light-absorbing compounds, found in photosynthetic organisms, that work in conjunction with chlorophyll ''a''. They include other forms of this pigment, such as chlorophyll ''b'' in green algal and higher plant antennae, while other algae may contain chlorophyll ''c'' or ''d''. In addition, there are many non-chlorophyll accessory pigments, such as carotenoids or phycobiliproteins, which also absorb light and transfer that light energy to photosystem chlorophyll. Some of these accessory pigments, in particular the carotenoids, also serve to absorb and dissipate excess light energy, or work as antioxidants. The large, physically associated group of chlorophylls and other accessory pigments is sometimes referred to as a ''pigment bed''. The different chlorophyll and non-chlorophyll pigments associated with the photosystems all have different absorption spectra, either because the spectra of the different chlorophyll pigments are modified by their local protei ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Chondrus Crispus
''Chondrus crispus''—commonly called Irish moss or carrageen moss (Irish ''carraigín'', "little rock")—is a species of red algae which grows abundantly along the rocky parts of the Atlantic coast of Europe and North America. In its fresh condition this protist is soft and cartilaginous, varying in color from a greenish-yellow, through red, to a dark purple or purplish-brown. The principal constituent is a mucilaginous body, made of the polysaccharide carrageenan, which constitutes 55% of its dry weight. The organism also consists of nearly 10% dry weight protein and about 15% dry weight mineral matter, and is rich in iodine and sulfur. When softened in water it has a sea-like odour and because of the abundant cell wall polysaccharides it will form a jelly when boiled, containing from 20 to 100 times its weight of water. Description ''Chondrus crispus'' is a relatively small sea alga, reaching up to a little more than 20 cm in length. It grows from a discoid holdfas ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Thylakoid
Thylakoids are membrane-bound compartments inside chloroplasts and cyanobacteria. They are the site of the light-dependent reactions of photosynthesis. Thylakoids consist of a thylakoid membrane surrounding a thylakoid lumen. Chloroplast thylakoids frequently form stacks of disks referred to as grana (singular: granum). Grana are connected by intergranal/stromal thylakoids, which join granum stacks together as a single functional compartment. In thylakoid membranes, chlorophyll pigments are found in packets called quantasomes. Each quantasome contains 230 to 250 chlorophyll molecules. Etymology The word ''Thylakoid'' comes from the Greek word ''thylakos'' or ''θύλακος'', meaning "sac" or "pouch". Thus, ''thylakoid'' means "sac-like" or "pouch-like". Structure Thylakoids are membrane-bound structures embedded in the chloroplast stroma. A stack of thylakoids is called a granum and resembles a stack of coins. Membrane The thylakoid membrane is the site of the ligh ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
