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Vertical Transmission
Vertical transmission of symbionts is the transfer of a microbial symbiont from the parent directly to the offspring. Many metazoan species carry symbiotic bacteria which play a mutualistic, commensal, or parasitic role. A symbiont is acquired by a host via horizontal, vertical, or mixed transmission. Fitness benefits Vertical transmission, passage of symbiotic microflora from parents to offspring, is common in species of animals which have parental care. There are fitness benefits in providing youths with established microorganism community early on. # Immune system development: parents microbes prime young immune system. # Disease resistance: because skin is already colonized by parental microbes, pathogen flora has a harder time to establish itself. # Digestive help: parental microbes might help with digestion, as a result, the young ones can survive on a diet which would not meet their nutritious needs otherwise. # Environmental adaptation: microflora might help t ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Symbiosis
Symbiosis (Ancient Greek : living with, companionship < : together; and ''bíōsis'': living) is any type of a close and long-term biological interaction, between two organisms of different species. The two organisms, termed symbionts, can for example be in Mutualism (biology), mutualistic, commensalism, commensalistic, or parasitism, parasitic relationships. In 1879, Heinrich Anton de Bary defined symbiosis as "the living together of unlike organisms". The term is sometimes more exclusively used in a restricted, mutualistic sense, where both symbionts contribute to each other's subsistence. This means that they benefit each other in some way. Symbiosis can be ''obligate'' (or ''obligative''), which means that one, or both of the organisms depend on each other for survival, or ''facultative'' (optional), when they can also subsist independently. Symbiosis is also classified by physical attachment. Symbionts forming a single body live ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Ecological Resilience
In ecology, resilience is the capacity of an ecosystem to respond to a perturbation or Disturbance (ecology), disturbance by resisting damage and subsequently recovering. Such perturbations and disturbances can include stochastic events such as fires, flooding, windstorms, insect population explosions, and human activities such as deforestation, fracking of the ground for oil extraction, pesticide sprayed in soil, and the Introduced species, introduction of exotic plant or animal species. Disturbances of sufficient Magnitude (mathematics), magnitude or duration can profoundly affect an ecosystem and may force an ecosystem to reach a Ecological threshold, threshold beyond which a different regime of processes and structures predominates. When such thresholds are associated with a critical or bifurcation theory, bifurcation point, these regime shifts may also be referred to as critical transitions. Human activities that adversely affect ecological resilience such as loss of biodiv ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Skin Flora
Skin flora, also called skin microbiota, refers to microbiota (community (ecology), communities of microorganisms) that reside on the skin, typically human skin. Many of them are bacterium, bacteria of which there are around 1,000 species upon human skin from nineteen Phylum, phyla. Most are found in the superficial layers of the Epidermis (skin), epidermis and the upper parts of hair follicles. Skin flora is usually non-pathogenic, and either commensalism, commensal (are not harmful to their host) or Mutualism (biology), mutualistic (offer a benefit). The benefits bacteria can offer include preventing transient pathogenic organisms from Infection#Colonization, colonizing the skin surface, either by competing for nutrients, secreting chemicals against them, or stimulating the skin's immune system. However, resident microbes can cause skin diseases and enter the blood system, creating life-threatening diseases, particularly in immunosuppressed people. A major non-human skin flora ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Human Gastrointestinal Microbiota
Gut microbiota, gut microbiome, or gut flora are the microorganisms, including bacteria, archaea, fungi, and viruses, that live in the digestive tracts of animals. The gastrointestinal metagenome is the aggregate of all the genomes of the gut microbiota. The gut is the main location of the human microbiome. The gut microbiota has broad impacts, including effects on colonization, resistance to pathogens, maintaining the intestinal epithelium, metabolizing dietary and pharmaceutical compounds, controlling immune function, and even behavior through the gut–brain axis. The microbial composition of the gut microbiota varies across regions of the digestive tract. The colon contains the highest microbial density of any human-associated microbial community studied so far, representing between 300 and 1000 different species. Bacteria are the largest and to date, best studied component and 99% of gut bacteria come from about 30 or 40 species. About 55% of the dry mass of feces is ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Vaginal Flora
Vaginal flora, vaginal microbiota or vaginal microbiome are the microorganisms that colonize the vagina. They were discovered by the German gynecologist Albert Döderlein in 1892 and are part of the overall human flora. The amount and type of bacteria present have significant implications for an individual's overall health. The primary colonizing bacteria of a healthy individual are of the genus ''Lactobacillus'', such as ''Lactobacillus crispatus, L. crispatus'', and the lactic acid they produce is thought to protect against infection by pathogenic species. Lactobacilli The primary colonizing bacteria of a healthy individual are of the genus ''Lactobacillus'' (90–95%), the most common being ''Lactobacillus crispatus, L. crispatus'', ''Lactobacillus iners, L. iners'', ''Lactobacillus jensenii, L. jensenii'', and ''Lactobacillus gasseri, L. gasseri''. Since the first description of lactobacilli by Döderlein, lactobacilli have been generally considered the gatekeepers of the ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Meristem
In cell biology, the meristem is a structure composed of specialized tissue found in plants, consisting of stem cells, known as meristematic cells, which are undifferentiated cells capable of continuous cellular division. These meristematic cells play a fundamental role in plant growth, regeneration, and acclimatization, as they serve as the source of all differentiated plant tissues and organs. They contribute to the formation of structures such as fruits, leaves, and seeds, as well as supportive tissues like stems and roots. Meristematic cells are totipotent, meaning they have the ability to differentiate into any plant cell type. As they divide, they generate new cells, some of which remain meristematic cells while others differentiate into specialized cells that typically lose the ability to divide or produce new cell types. Due to their active division and undifferentiated nature, meristematic cells form the foundation for the formation of new plant organs and the c ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Endosperm
The endosperm is a tissue produced inside the seeds of most of the flowering plants following double fertilization. It is triploid (meaning three chromosome sets per nucleus) in most species, which may be auxin-driven. It surrounds the Embryo#Plant embryos, embryo and provides nutrition in the form of starch, though it can also contain Vegetable oil, oils and protein. This can make endosperm a source of nutrition in animal diet. For example, wheat endosperm is ground into flour for bread (the rest of the grain is included as well in whole wheat flour), while barley endosperm is the main source of sugars for beer production. Other examples of endosperm that forms the bulk of the edible portion are coconut "meat" and coconut "water", and Maize, corn. Some plants, such as certain orchids, lack endosperm in their seeds. Ancestral flowering plants have seeds with small embryos and abundant endosperm. In some modern flowering plants the embryo occupies most of the seed and the endosperm ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Endophyte
An endophyte is an endosymbiont, often a bacterium or fungus, that lives within a plant for at least part of its life cycle without causing apparent disease. Endophytes are ubiquitous and have been found in all species of plants studied to date; however, most of the endophyte/plant relationships are not well understood. Some endophytes may enhance host growth and nutrient acquisition and improve the plant's ability to tolerate abiotic stresses, such as drought, and decrease biotic stresses by enhancing plant resistance to insects, pathogens and herbivores. Although endophytic bacteria and fungi are frequently studied, endophytic archaea are increasingly being considered for their role in plant growth promotion as part of the core microbiome of a plant. History Endophytes were first described by the German botanist Johann Heinrich Friedrich Link in 1809. They were thought to be plant parasitic fungi and they were later termed as "microzymas" by the French scientist Béchamp. The ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Bacteriocyte
A bacteriocyte ( Greek for ''bacteria cell''), also known as a mycetocyte, is a specialized adipocyte found primarily in certain insects such as aphids, tsetse flies, German cockroaches, weevils, and ants. These cells contain endosymbiotic organisms such as bacteria and fungi, which provide essential amino acids and other chemicals to their host. Bacteriocytes may aggregate into a specialized organ called the bacteriome. Endosymbiosis with microorganisms is common in insects. More than 10% of insect species rely upon intracellular bacteria for their development and survival.Baumann P, Moran NA, Baumann L, editors. (2000) Bacteriocyte-associated endosymbionts of insects. In: Dworkin M, editor. The prokaryotes nline New York: Springer. Available: http://link.springer.de/link/service/books/10125/ . Endosymbionts and their relationships with their hosts are diverse both functionally and genetically. However, the host cell in which bacterial and fungal endosymbionts res ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Intracellular Parasite
Intracellular parasites are microparasites that are capable of growing and reproducing inside the cells of a host. They are also called intracellular pathogens. Types There are two main types of intracellular parasites: Facultative and Obligate. Facultative intracellular parasites are capable of living and reproducing in or outside of host cells. Obligate intracellular parasites, on the other hand, need a host cell to live and reproduce. Many of these types of cells require specialized host types, and invasion of host cells occurs in different ways. Facultative Facultative intracellular parasites are capable of living and reproducing either inside or outside cells. Bacterial examples include: Fungal examples include: Obligate Obligate intracellular parasites cannot reproduce outside their host cell, meaning that the parasite's reproduction is entirely reliant on intracellular resources. All viruses are obligate intracellular parasites. Bacterial examples (that affect ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Organelle
In cell biology, an organelle is a specialized subunit, usually within a cell (biology), cell, that has a specific function. The name ''organelle'' comes from the idea that these structures are parts of cells, as Organ (anatomy), organs are to the Human body, body, hence ''organelle,'' the suffix ''-elle'' being a diminutive. Organelles are either separately enclosed within their own lipid bilayers (also called membrane-bounded organelles) or are spatially distinct functional units without a surrounding lipid bilayer (non-membrane bounded organelles). Although most organelles are functional units within cells, some functional units that extend outside of cells are often termed organelles, such as cilia, the flagellum and archaellum, and the trichocyst (these could be referred to as membrane bound in the sense that they are attached to (or bound to) the membrane). Organelles are identified by microscopy, and can also be purified by cell fractionation. There are many types of organe ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Germline
In biology and genetics, the germline is the population of a multicellular organism's cells that develop into germ cells. In other words, they are the cells that form gametes ( eggs and sperm), which can come together to form a zygote. They differentiate in the gonads from primordial germ cells into gametogonia, which develop into gametocytes, which develop into the final gametes. This process is known as gametogenesis. Germ cells pass on genetic material through the process of sexual reproduction. This includes fertilization, recombination and meiosis. These processes help to increase genetic diversity in offspring. Certain organisms reproduce asexually via processes such as apomixis, parthenogenesis, autogamy, and cloning. Apomixis and Parthenogenesis both refer to the development of an embryo without fertilization. The former typically occurs in plants seeds, while the latter tends to be seen in nematodes, as well as certain species of reptiles, birds, and fish. Autogamy ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
