| Udoteaceae | |
|---|---|
 | |
| Chlorodesmis fastigiata | |
Scientific classification  | |
| (unranked): | Viridiplantae |
| Division: | Chlorophyta |
| Class: | Ulvophyceae |
| Order: | Bryopsidales |
| Family: | Udoteaceae J. Agardh, 1887 |
| Genera [1] | |
Udoteaceae is a family of green algae, in the order Bryopsidales. [1]
Udoteaceae is a family of green algae that belongs to the order Bryopsidales. Udoteaceae are most abundant in reef ecosystems as it serves an important ecological role as a primary producer, contributor to carbonate fluxes, and it serves as protection or food for other marine organisms. [2] [3]
Udoteaceae is the most morphologically complex family belonging to the order Bryopsidales. Along with its high morphological complexity, Udoteaceae also has high species diversity. There are fourteen genera, eight extant, belonging to the family Udoteaceae, however only four are officially accepted. There are twenty-four species belonging to these genera, however because genetic information on Udoteaceae is limited, these species are classified primarily from morphological features. [2] [3]
Udoteaceae's structure is siphonous and composed of a giant, multinucleate tubular cell. Udoteaceae contains taxa that are either calcified or non-calcified. The species range from simple siphonous filaments to complex multiaxial structures. Genera from Udoteaceae include tufts of uncalcified and free filaments, a brush-like calcified thallus, or calcareous compact fan-shaped blades. [2] [3]
Both sexual and asexual reproduction is observed under green algae (Chlorophyta). However, Bryopsidales, the order Udoteaceae belongs to, sexual reproduction is most common. [4]
Sexual reproduction utilizes meiosis, which will produce gametes, germ cells from two parents. The sperm cells and the egg cells will fuse, making a zygote. In most multicellular green algae, the sperm cells are small and motile, and the egg cells are large and immotile. However, in simple multicellular or unicellular algae, germ cells are typically isogamous, which means the germ cells from both parents are the same size. Ulvophyceae, the class Udoteaceae belongs to, contains both multicellular and multinucleated organisms. However, Bryopsidales, the order for Udoteaceae, multinucleated organisms, so it can be assumed that Udoteaceae is as well. [5]
The time it takes for the gametes to be fertilized after being released varies greatly among the green algae (Chlorophyta). The genera Udotea, which belongs to the family Udoteaceae, can take up to ninety-six hours after the gametes are released before being fertilized. [6]
Udoteaceae's origin dates back about 216 mya (million years ago), which would be around the Late Triassic period. Most of the genera from Udoteaceae originated between 66 and 23 mya (Paleogene period). [3] [7]
Fossil evidence of Udoteaceae suggests that the family originated from the western Tethys Sea. The Tethys Sea was present until 66 mya, and it was located between the two continents Gondwana and Laurasia. The center of diversity shifted from the Western Tethys to the Central Indo-Pacific once the archipelagos were formed. [7]
Three centers of diversity have been identified for Udoteaceae: The Central Indo-Pacific, the Western Indian Ocean, and the Greater Caribbean region. The Central-Indo Pacific is considered the center of origin, the Western Indian Ocean is considered the center of origin and accumulation, and finally the Greater Caribbean is considered the more recent center of origin. [7]
Udoteaceae are widespread geographically, its species are mostly found in tropical and subtropical regions. They also can be found in temperate regions of the Atlantic, Pacific, and Indian Oceans, as well as in the Red and Mediterranean seas. They are abundant in reef ecosystems and serve an important ecological role. Udoteaceae play a major part in the ecological system as a primary producer and as a contributor to carbonate fluxes. They are also important in the food chain as they are used for food by organisms, and they can be used by smaller organisms for hiding from predators. [6] [7] As they are primary producers, access to light is important for Udoteaceae, so they will be more common in shallow and clearer waters.
The Chlorophyceae are one of the classes of green algae, distinguished mainly on the basis of ultrastructural morphology. They are usually green due to the dominance of pigments chlorophyll a and chlorophyll b. The chloroplast may be discoid, plate-like, reticulate, cup-shaped, spiral- or ribbon-shaped in different species. Most of the members have one or more storage bodies called pyrenoids located in the chloroplast. Pyrenoids contain protein besides starch. Some green algae may store food in the form of oil droplets. They usually have a cell wall made up of an inner layer of cellulose and outer layer of pectose.
Chlorophyta is a taxon of green algae informally called chlorophytes. The name is used in two very different senses, so care is needed to determine the use by a particular author. In older classification systems, it is a highly paraphyletic group of all the green algae within the green plants (Viridiplantae) and thus includes about 7,000 species of mostly aquatic photosynthetic eukaryotic organisms. In newer classifications, it is the sister clade of the streptophytes/charophytes. The clade Streptophyta consists of the Charophyta in which the Embryophyta emerged. In this latter sense the Chlorophyta includes only about 4,300 species. About 90% of all known species live in freshwater. Like the land plants, green algae contain chlorophyll a and chlorophyll b and store food as starch in their plastids.
Volvox is a polyphyletic genus of chlorophyte green algae in the family Volvocaceae. Volvox species form spherical colonies of up to 50,000 cells, and for this reason they are sometimes called globe algae. They live in a variety of freshwater habitats, and were first reported by Antonie van Leeuwenhoek in 1700. Volvox diverged from unicellular ancestors approximately 200 million years ago.
Alternation of generations is the predominant type of life cycle in plants and algae. In plants both phases are multicellular: the haploid sexual phase – the gametophyte – alternates with a diploid asexual phase – the sporophyte.
In cellular biology, a somatic cell, or vegetal cell, is any biological cell forming the body of a multicellular organism other than a gamete, germ cell, gametocyte or undifferentiated stem cell. Somatic cells compose the body of an organism and divide through the process of binary fission and mitotic division.
A unicellular organism, also known as a single-celled organism, is an organism that consists of a single cell, unlike a multicellular organism that consists of multiple cells. Organisms fall into two general categories: prokaryotic organisms and eukaryotic organisms. Most prokaryotes are unicellular and are classified into bacteria and archaea. Many eukaryotes are multicellular, but some are unicellular such as protozoa, unicellular algae, and unicellular fungi. Unicellular organisms are thought to be the oldest form of life, with early protocells possibly emerging 3.8–4.0 billion years ago.
Gametogenesis is a biological process by which diploid or haploid precursor cells undergo cell division and differentiation to form mature haploid gametes. Depending on the biological life cycle of the organism, gametogenesis occurs by meiotic division of diploid gametocytes into various gametes, or by mitosis. For example, plants produce gametes through mitosis in gametophytes. The gametophytes grow from haploid spores after sporic meiosis. The existence of a multicellular, haploid phase in the life cycle between meiosis and gametogenesis is also referred to as alternation of generations.
In biology, a biological life cycle is a series of stages of the life of an organism, that begins as a zygote, often in an egg, and concludes as an adult that reproduces, producing an offspring in the form of a new zygote which then itself goes through the same series of stages, the process repeating in a cyclic fashion.
The green algae are a group consisting of the Prasinodermophyta and its unnamed sister which contains the Chlorophyta and Charophyta/Streptophyta. The land plants (Embryophytes) have emerged deep in the Charophyte alga as a sister of the Zygnematophyceae. Since the realization that the Embryophytes emerged within the green algae, some authors are starting to include them. The completed clade that includes both green algae and embryophytes is monophyletic and is referred to as the clade Viridiplantae and as the kingdom Plantae. The green algae include unicellular and colonial flagellates, most with two flagella per cell, as well as various colonial, coccoid and filamentous forms, and macroscopic, multicellular seaweeds. There are about 22,000 species of green algae. Many species live most of their lives as single cells, while other species form coenobia (colonies), long filaments, or highly differentiated macroscopic seaweeds.
A coenocyte is a multinucleate cell which can result from multiple nuclear divisions without their accompanying cytokinesis, in contrast to a syncytium, which results from cellular aggregation followed by dissolution of the cell membranes inside the mass. The word syncytium in animal embryology is used to refer to the coenocytic blastoderm of invertebrates. A coenocytic colony is referred to as a coenobium, and most coenobia are composed of a distinct number of cells, often as a multiple of two.
Caulerpa is a genus of seaweeds in the family Caulerpaceae. They are unusual because they consist of only one cell with many nuclei, making them among the biggest single cells in the world.
Caulerpa racemosa is a species of edible green alga, a seaweed in the family Caulerpaceae. It is commonly known as sea grapes and is found in many areas of shallow sea around the world. Despite the name, it is not related to grapes. There are a number of different forms and varieties, and one that appeared in the Mediterranean Sea in 1990, which is giving cause for concern as an invasive species.
The Ectasian Period is the second geologic period in the Mesoproterozoic Era and lasted from 1400 Mya ago to 1200 Mya. Instead of being based on stratigraphy, these dates are defined chronometrically.
Halimeda is a genus of green macroalgae. The algal body (thallus) is composed of calcified green segments. Calcium carbonate is deposited in its tissues, making it inedible to most herbivores. However one species, Halimeda tuna, was described as pleasant to eat with oil, vinegar, and salt.
Codium is a genus of edible green macroalgae under the order Bryopsidales. The genus name is derived from a Greek word that pertains to the soft texture of its thallus. One of the foremost experts on Codium taxonomy was Paul Claude Silva at the University of California, Berkeley. P.C. Silva was able to describe 36 species for the genus and in honor of his work on Codium, the species C. silvae was named after the late professor.
Rhipiliopsis is a genus of green algae in the family Rhipiliaceae. Johnson-sea-linkia is a synonym.
Udotea is a genus of green algae in the family Udoteaceae.
Caulerpa prolifera is a species of green alga, a seaweed in the family Caulerpaceae. It is the type species of the genus Caulerpa, the type location being Alexandria, Egypt. It grows rapidly and forms a dense mass of vegetation on shallow sandy areas of the sea.
Bracteamorpha is a genus of green algae in the order Sphaeropleales, and is the only genus in the family Bracteamorphaceae. It contains a single species, Bracteamorpha trainorii.
Germ-Soma Differentiation is the process by which organisms develop distinct germline and somatic cells. The development of cell differentiation has been one of the critical aspects of the evolution of multicellularity and sexual reproduction in organisms. Multicellularity has evolved upwards of 25 times, and due to this there is great possibility that multiple factors have shaped the differentiation of cells. There are three general types of cells: germ cells, somatic cells, and stem cells. Germ cells lead to the production of gametes, while somatic cells perform all other functions within the body. Within the broad category of somatic cells, there is further specialization as cells become specified to certain tissues and functions. In addition, stem cell are undifferentiated cells which can develop into a specialized cell and are the earliest type of cell in a cell lineage. Due to the differentiation in function, somatic cells are found ony in multicellular organisms, as in unicellular ones the purposes of somatic and germ cells are consolidated in one cell.
| Authority control databases: National |
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