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Osmotrophy
Osmotrophy is a form of heterotrophic nutrition and a cellular feeding mechanism involving the direct absorption of dissolved organic compounds by osmosis. Organisms that use osmotrophy are called osmotrophs. Osmotrophy is used by diverse groups of organisms. Organisms that use osmotrophy include microorganisms like bacteria, many species of protists and most fungi. Invertebrate animal groups like molluscs, sponges, corals, brachiopods and echinoderms may use osmotrophic feeding as a supplemental food source. A common subset of osmotrophy is lysotrophy, in which organisms secrete enzymes into the extracellular environment to break down macromolecules into smaller, soluble molecules for absorption. Process Osmotrophy, as a means of gathering nutrients in microscopic organisms, relies on the cellular surface area to ensure that proper diffusion of nutrients occurs in the cell. Some osmotrophs may have an internal digestive system, while still using osmosis as a way to gain supple ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Protist
A protist ( ) or protoctist is any eukaryotic organism that is not an animal, land plant, or fungus. Protists do not form a natural group, or clade, but are a paraphyletic grouping of all descendants of the last eukaryotic common ancestor excluding land plants, animals, and fungi. Protists were historically regarded as a separate taxonomic kingdom known as Protista or Protoctista. With the advent of phylogenetic analysis and electron microscopy studies, the use of Protista as a formal taxon was gradually abandoned. In modern classifications, protists are spread across several eukaryotic clades called supergroups, such as Archaeplastida ( photoautotrophs that includes land plants), SAR, Obazoa (which includes fungi and animals), Amoebozoa and " Excavata". Protists represent an extremely large genetic and ecological diversity in all environments, including extreme habitats. Their diversity, larger than for all other eukaryotes, has only been discovered in rece ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Phagotrophy
Phagocytosis () is the process by which a cell uses its plasma membrane to engulf a large particle (≥ 0.5 μm), giving rise to an internal compartment called the phagosome. It is one type of endocytosis. A cell that performs phagocytosis is called a phagocyte. In a multicellular organism's immune system, phagocytosis is a major mechanism used to remove pathogens and cell debris. The ingested material is then digested in the phagosome. Bacteria, dead tissue cells, and small mineral particles are all examples of objects that may be phagocytized. Some protozoa use phagocytosis as means to obtain nutrients. The two main cells that do this are the Macrophages and the Neutrophils of the immune system. Where phagocytosis is used as a means of feeding and provides the organism part or all of its nourishment, it is called phagotrophy and is distinguished from osmotrophy, which is nutrition taking place by absorption. History The history of phagocytosis represents the scientific ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Mixotrophy
A mixotroph is an organism that uses a mix of different sources of energy and carbon, instead of having a single trophic mode, on the continuum from complete autotrophy to complete heterotrophy. It is estimated that mixotrophs comprise more than half of all microscopic plankton. There are two types of eukaryotic mixotrophs. There are those with their own chloroplasts – including those with endosymbionts providing the chloroplasts. And there are those that acquire them through kleptoplasty, or through symbiotic associations with prey, or through 'enslavement' of the prey's organelles.Leles S G et al, (2017). Oceanic protists with different forms of acquired phototrophy display contrasting biogeographies and abundance, ''Proceedings of the Royal Society B: Biological Sciences''. Possible combinations are photo- and chemotrophy, litho- and organotrophy ( osmotrophy, phagotrophy and myzocytosis), auto- and heterotrophy or other combinations of these. Mixotrophs can be either eu ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Fungus
A fungus (: fungi , , , or ; or funguses) is any member of the group of eukaryotic organisms that includes microorganisms such as yeasts and mold (fungus), molds, as well as the more familiar mushrooms. These organisms are classified as one of the kingdom (biology)#Six kingdoms (1998), traditional eukaryotic kingdoms, along with Animalia, Plantae, and either Protista or Protozoa and Chromista. A characteristic that places fungi in a different kingdom from plants, bacteria, and some protists is chitin in their cell walls. Fungi, like animals, are heterotrophs; they acquire their food by absorbing dissolved molecules, typically by secreting digestive enzymes into their environment. Fungi do not photosynthesize. Growth is their means of motility, mobility, except for spores (a few of which are flagellated), which may travel through the air or water. Fungi are the principal decomposers in ecological systems. These and other differences place fungi in a single group of related o ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Mixotrophic
A mixotroph is an organism that uses a mix of different sources of energy and carbon, instead of having a single trophic mode, on the continuum from complete autotrophy to complete heterotrophy. It is estimated that mixotrophs comprise more than half of all microscopic plankton. There are two types of eukaryotic mixotrophs. There are those with their own chloroplasts – including those with endosymbionts providing the chloroplasts. And there are those that acquire them through kleptoplasty, or through symbiotic associations with prey, or through 'enslavement' of the prey's organelles.Leles S G et al, (2017). Oceanic protists with different forms of acquired phototrophy display contrasting biogeographies and abundance, ''Proceedings of the Royal Society B: Biological Sciences''. Possible combinations are photo- and chemotrophy, litho- and organotrophy ( osmotrophy, phagotrophy and myzocytosis), auto- and heterotrophy or other combinations of these. Mixotrophs can be either eu ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Heterotrophic Nutrition
Heterotrophic nutrition is a mode of nutrition in which organisms depend upon other organisms for food to survive. They can't make their own food like Green plants. Heterotrophic organisms have to take in all the organic substances they need to survive. All animals, certain types of fungi, and non-photosynthesizing plants are heterotrophic. In contrast, green plants, red algae, brown algae, and cyanobacteria are all autotrophs, which use photosynthesis to produce their own food from sunlight. Some fungi may be saprotrophic, meaning they will extracellularly secrete enzymes onto their food to be broken down into smaller, soluble molecules which can diffuse back into the fungus. Description All eukaryotes except for green plants and algae are unable to manufacture their own food: They obtain food from other organisms. This mode of nutrition is also known as heterotrophic nutrition. All heterotrophs (except blood and gut parasites) have to convert solid food into soluble compounds w ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Diffusion
Diffusion is the net movement of anything (for example, atoms, ions, molecules, energy) generally from a region of higher concentration to a region of lower concentration. Diffusion is driven by a gradient in Gibbs free energy or chemical potential. It is possible to diffuse "uphill" from a region of lower concentration to a region of higher concentration, as in spinodal decomposition. Diffusion is a stochastic process due to the inherent randomness of the diffusing entity and can be used to model many real-life stochastic scenarios. Therefore, diffusion and the corresponding mathematical models are used in several fields beyond physics, such as statistics, probability theory, information theory, neural networks, finance, and marketing. The concept of diffusion is widely used in many fields, including physics (Molecular diffusion, particle diffusion), chemistry, biology, sociology, economics, statistics, data science, and finance (diffusion of people, ideas, data and price v ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Heterotrophy
A heterotroph (; ) is an organism that cannot produce its own food, instead taking nutrition from other sources of organic carbon, mainly plant or animal matter. In the food chain, heterotrophs are primary, secondary and tertiary consumers, but not producers. Living organisms that are heterotrophic include all animals and fungi, some bacteria and protists, and many parasitic plants. The term heterotroph arose in microbiology in 1946 as part of a classification of microorganisms based on their type of nutrition. The term is now used in many fields, such as ecology, in describing the food chain. Heterotrophs occupy the second and third trophic levels of the food chain while autotrophs occupy the first trophic level. Heterotrophs may be subdivided according to their energy source. If the heterotroph uses chemical energy, it is a chemoheterotroph (e.g., humans and mushrooms). If it uses light for energy, then it is a photoheterotroph (e.g., green non-sulfur bacteria). Heterotrop ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Autotrophy
An autotroph is an organism that can convert abiotic sources of energy into energy stored in organic compounds, which can be used by other organisms. Autotrophs produce complex organic compounds (such as carbohydrates, fats, and proteins) using carbon from simple substances such as carbon dioxide,Morris, J. et al. (2019). "Biology: How Life Works", 3rd edition, W. H. Freeman. generally using energy from light or inorganic chemical reactions. Autotrophs do not need a living source of carbon or energy and are the producers in a food chain, such as plants on land or algae in water. Autotrophs can reduce carbon dioxide to make organic compounds for biosynthesis and as stored chemical fuel. Most autotrophs use water as the reducing agent, but some can use other hydrogen compounds such as hydrogen sulfide. The primary producers can convert the energy in the light (phototroph and photoautotroph) or the energy in inorganic chemical compounds (chemotrophs or chemolithotrophs) ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Energy
Energy () is the physical quantity, quantitative physical property, property that is transferred to a physical body, body or to a physical system, recognizable in the performance of Work (thermodynamics), work and in the form of heat and light. Energy is a Conservation law, conserved quantity—the law of conservation of energy states that energy can be Energy transformation, converted in form, but not created or destroyed. The unit of measurement for energy in the International System of Units (SI) is the joule (J). Forms of energy include the kinetic energy of a moving object, the potential energy stored by an object (for instance due to its position in a Classical field theory, field), the elastic energy stored in a solid object, chemical energy associated with chemical reactions, the radiant energy carried by electromagnetic radiation, the internal energy contained within a thermodynamic system, and rest energy associated with an object's rest mass. These are not mutual ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Decomposition
Decomposition is the process by which dead organic substances are broken down into simpler organic or inorganic matter such as carbon dioxide, water, simple sugars and mineral salts. The process is a part of the nutrient cycle and is essential for recycling the finite matter that occupies physical space in the biosphere. Bodies of living organisms begin to decompose shortly after death. Although no two organisms decompose in the same way, they all undergo the same sequential stages of decomposition. Decomposition can be a gradual process for organisms that have extended periods of dormancy. One can differentiate ''abiotic'' decomposition from ''biotic'' decomposition ( biodegradation); the former means "the degradation of a substance by chemical or physical processes", e.g., hydrolysis; the latter means "the metabolic breakdown of materials into simpler components by living organisms", typically by microorganisms. Animals, such as earthworms, also help decompose the organ ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
