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Topic Review
Anoxia Tolerance in Rice Seeds under Submergence
Submergence in rice fields creating inundation stress and realizing anoxia or hypoxia is a problem in agriculture. Seeds under this oxygen deficit are faced with fermentative respiration, where the end product would be poisoning the tissue viability. This is more aggravated in direct seeded rice cultivation with the accumulation of lactate as a poison. 
  • 231
  • 21 Aug 2023
Topic Review
Anoxygenic Photosynthesis in Photolithotrophic Sulfur Bacteria
Hydrogen sulfide is a toxic compound that can affect various groups of water microorganisms. Photolithotrophic sulfur bacteria including Chromatiaceae and Chlorobiaceae are able to convert inorganic substrate (hydrogen sulfide and carbon dioxide) into organic matter deriving energy from photosynthesis. This process takes place in the absence of molecular oxygen and is referred to as anoxygenic photosynthesis, in which exogenous electron donors are needed. These donors may be reduced sulfur compounds such as hydrogen sulfide. 
  • 719
  • 22 Apr 2022
Topic Review
Ant–Pollinator Conflict in Extrafloral Nectary-Bearing Plants
The net outcomes of mutualisms are mediated by the trade-offs between the costs and benefits provided by both partners. This trade-off has important implications for understanding the evolution of extrafloral nectaries (EFNs), an adaptation that has repeatedly evolved throughout the flowering plant clade.
  • 146
  • 12 Mar 2024
Topic Review
Antagonistic Coevolution
Sexual antagonistic co-evolution is the relationship between males and females where sexual morphology changes over time to counteract the opposite's sex traits to achieve the maximum reproductive success. This has been compared to an arms race between sexes. In many cases, male mating behavior is detrimental to the female's fitness. For example, when insects reproduce by means of traumatic insemination, it is very disadvantageous to the female's health. During mating, males will try to inseminate as many females as possible, however, the more times a female's abdomen is punctured, the less likely she is to survive. Females that possess traits to avoid multiple matings will be more likely to survive, resulting in a change in morphology. In males, genitalia is relatively simple and more likely to vary among generations compared to female genitalia. This results in a new trait that females have to avoid in order to survive. Additionally, sexual antagonistic co-evolution can be the cause of rapid evolution, as is thought to be the case in seminal proteins known as Acps in species of Drosophila melanogaster. While Acps facilitate the mutually beneficial outcome of increased progeny production, several Acps have detrimental effects on female fitness as they are toxic and shorten her lifespan. This leads to antagonistic co-evolution, as the female must evolve in order to defend herself. When female Drosophila melanogaster are experimentally prevented from co-evolving with males, males rapidly adapt to the static female phenotype. This male adaptation leads to a reduction in female survivorship, which is mediated by an increased rate of remating and increased toxicity of Acps in seminal fluid. Since non-reproductive proteins do not feel the same evolutionary pressure as Acps, they are not evolving nearly as quickly. Consistent with the arms race theory, DNA analyses reveal a two-fold increase in Acp divergence relative to non-reproductive proteins
  • 239
  • 19 Oct 2022
Topic Review
Antagonistic Yeasts
Antagonistic yeasts (also known as biocontrol yeasts) are promising substitutes for chemical fungicides in the control of postharvest decay owing to their widespread distribution, antagonistic ability, environmentally friendly nature, and safety for humans.
  • 1.2K
  • 26 Oct 2020
Topic Review
Antarctic cryptoendolithic communities
The Antarctic cryptoendolithic communities are self-supporting assemblages of phototrophic and heterotrophic microorganisms, including bacteria, Cyanobacteria, Chlorophyta and both free-living and lichen-forming fungi. These are among the most stress-resistant organisms known to date, constantly living to the edge of their physiological adaptability.
  • 820
  • 27 Oct 2020
Topic Review
Antarctic Fur Seal
The Antarctic Fur Seal, scientifically known as Arctocephalus gazella, is a charismatic marine mammal native to the subantarctic and Antarctic regions. Recognized for its dense fur coat, robust build, and distinctive facial features, this species is a top predator in its icy habitat. Antarctic Fur Seals play a vital role in marine ecosystems, influencing prey populations and contributing to the overall health of polar environments.
  • 282
  • 15 Mar 2024
Topic Review
Antarctic Marine Fungi
Despite the harsh conditions, fungi are ubiquitously present in Antarctic ecosystems. The key to fungal success can be due to the vast array of specialized molecules, which allowed their colonization in almost every habitat of our Planet. In Antarctic marine environments, the fungal specific adaptions to low temperatures lead to the production of structurally novel enzymes and secondary metabolites that provide competitive advantages over other microorganisms. The bioprospecting of Antarctic fungi for new bioactive compounds and enzymes is important not only for elucidating their ecological role but also useful for developing blue biotechnologies. 
  • 1.2K
  • 01 Jun 2021
Topic Review
Antarctic Soil Fungi for Bioprospecting
Antarctica, one of the harshest environments in the world, has been successfully colonized by extremophilic, psychrophilic, and psychrotolerant microorganisms, facing a range of extreme conditions. Fungi are the most diverse taxon in the Antarctic ecosystems, including soils. Genetic adaptation to this environment results in the synthesis of a range of metabolites with different functional roles in relation to the biotic and abiotic environmental factors. Cold-adapted enzymes and other bioactive secondary metabolites with new biological properties of potential biotechnological interest have been reported to date from filamentous fungi and yeasts inhabiting Antarctic soils, and further could be recovered. Antarctic fungi are a source of enzymes and secondary metabolites with an incredible application potential, deserving to be studied always in agreement with the provisions of Article III.1 of the Antarctic Treaty, concerning scientific exchanges and the availability of scientific observations and results from the continent.
  • 631
  • 09 Sep 2020
Topic Review
Antenna
Antennae (Template:Singular antenna), sometimes referred to as "feelers", are paired appendages used for sensing in arthropods. Antennae are connected to the first one or two segments of the arthropod head. They vary widely in form but are always made of one or more jointed segments. While they are typically sensory organs, the exact nature of what they sense and how they sense it is not the same in all groups. Functions may variously include sensing touch, air motion, heat, vibration (sound), and especially smell or taste. Antennae are sometimes modified for other purposes, such as mating, brooding, swimming, and even anchoring the arthropod to a substrate. Larval arthropods have antennae that differ from those of the adult. Many crustaceans, for example, have free-swimming larvae that use their antennae for swimming. Antennae can also locate other group members if the insect lives in a group, like the ant. The common ancestor of all arthropods likely had one pair of uniramous (unbranched) antenna-like structures, followed by one or more pairs of biramous (having two major branches) leg-like structures, as seen in some modern crustaceans and fossil trilobites. Except for the chelicerates and proturans, which have none, all non-crustacean arthropods have a single pair of antennae.
  • 2.2K
  • 25 Oct 2022
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