#scientific term

• Amphiderm — An anatomical formation or double cellular envelope found in certain plant organs, characterized by the presence of two distinct protective layers located at the periphery of tissues. In plant morphology, this structural element protects internal structures against water loss or external aggressions in habitats with extreme ecological conditions.
• Amphidiploidy — A genetic state or a particular type of polyploidy (allopolyploidy) characterized by the presence of a complete diploid set of chromosomes derived from two different parental species following hybridization and subsequent chromosome doubling. This structural phenomenon guarantees the fertility of the hybrid, allowing normal pairing of homologous chromosomes during meiosis, and is widely used in plant genetic engineering to create new plant varieties.
• Amphiphloic — Having or characterized by the presence of phloem tissue on both sides of the xylem; an adjective used in plant anatomy to define a structural type of central cylinder (amphiphloic siphonostele or solenostele), commonly found in ferns, where the central pith is successively surrounded by an inner ring of phloem, a central ring of xylem, and an outer ring of phloem.
• Amphiphotic — Exhibiting tolerance, structural adaptation, or equal utilization of two light intensities (strong and weak); in marine ecology and limnology, it describes an organism, species, or aquatic transitional zone capable of functioning optimally both in the well-lit surface environment (euphotic zone) and in the twilight environment (oligophotic or mesophotic zone).
• Amphigamous — Relating to amphigamy or presenting the characteristics of this state; describes cryptogamous plants (such as mosses or ferns) whose reproductive organs or fertilization modes are not obvious or structured in the form of visible flowers, reproduction being based on the alternation of generations and the hybrid fusion of hidden gametes.
• Amphigamy — A mode of reproduction characteristic of cryptogamous plants, defined by the absence of obvious floral organs and the occurrence of fertilization through the union of simple gametes or hidden spores; also, in an extended biological sense, it can designate the symmetrical cellular fusion or direct hybridization between two genetic lines without macro-structural sexual differentiation.
• Amphigastria — Minute, rudimentary, structurally modified leaves arranged in a median row on the ventral side of the stem in most species of leafy liverworts (Jungermanniales). These plant microstructures have the role of retaining water through capillarity and protecting the stem against dehydration in forest or rocky habitats.
• Amphigenous — Growing, developing, or producing on both sides of a plant organ (such as leaves or stems); in mycology, it describes a type of parasitic fungus whose reproductive structures (conidia, spores) structurally appear and develop on both the upper and lower surfaces of the host plant's leaf.
• Amphigynous — Relating to or presenting the characteristics of female reproductive structures arranged symmetrically or on both sides of an organ; in botany and mycology, it describes a development pattern or cellular network (partially related to amphigyny) where male organs (antheridia) circularly surround or penetrate the base of the female organ (oogonium), specific to certain phytopathogenic oomycetes (such as the genus Phytophthora).
• Amphigoric — Producing offspring of both sexes in approximately equal proportions; a term used in population genetics and reproductive studies (correlated with amphigyry/amphigurism) to describe a species, genetic line, or crossbreed that maintains a structurally balanced numerical ratio between males and females within the resulting generations.
• Amphimorphy — A property, biological state, or structural phenomenon consisting of the coexistence or succession of two different forms or morphological aspects within the same organism, organ, or mineralogical compound. This adaptive mechanism is studied within comparative morphology and crystallography.
• Amphineuran — A primitive marine mollusk belonging to the class Amphineura (in classical classifications), characterized by perfect bilateral symmetry, a structural nervous system composed of two pairs of longitudinal cords united by commissures, and a shell consisting of eight articulated calcareous plates (such as chitons) or a vermiform body lacking a shell. As an adjective, it describes an anatomical feature or an organism associated with this group.
• Lancelet — A small (a few centimeters), primitive marine vertebrate with a translucent, elongated body pointed at both ends, belonging to the phylum Cephalochordata. This structural organism represents an essential evolutionary transition link, as it retains the notochord, neural tube, and pharyngeal slits throughout its entire life, serving as a classic model in the study of comparative chordate anatomy.
• Amphiplasm — A hybrid cytoplasmic formation or unified protoplasmic mass, structurally formed during the early stages of amphimixis through the complete merging of the cytoplasm of both gametes (male and female). This stage precedes the actual nuclear fusion (karyogamy) and ensures the rearrangement of cellular organelles inside the newly developing zygote.
• Amphiplasty — A cytogenetic phenomenon or structural chromosomal anomaly arising following interspecific hybridization, characterized by the constant morphological modification (alteration of shape, secondary constrictions, or nucleolar organizers) of one set of chromosomes derived from one parental species under the influence of the cytoplasm or genome of the partner species.
• Amphipod — A small malacostracan crustacean belonging to the order Amphipoda, characterized by the absence of a carapace, a laterally compressed body, and legs structurally adapted for different functions (some for walking, others for swimming or jumping). Most species live in marine or freshwater environments (such as the beach flea or the genus Gammarus), playing an essential ecological role in aquatic food webs.
• Amylosphere — A macromolecular formation or spherical cytoplasmic inclusion of a polysaccharide nature, developing inside certain plant cells or lower organisms. It represents a dense structural agglomeration resembling a microscopic starch grain, serving as a focused storage area for reserve carbohydrates.
• Anecdotal — Pertaining to or having the character of an anecdote; fragmented, informal, or minor in narrative scope. In scientific or historical methodology, it describes information or arguments based on isolated, subjective, and statistically unverifiable evidence that does not reflect a general rule.
• Anthraco — A neologic combining form (pseudoprefix) utilized as a structural lexical base in the formation of technical and scientific terms, meaning 'coal', 'pitch-black', or 'referring to anthracite or anthrax'. In highly isolated or commercial cases, it can function as an independent neuter noun designating a material, a pigment, or a texture that mimics the chromatic and structural density of superior coal in industrial painting or finishing processes.
• Annulo- — A combining form derived from Latin (anulus), used in scientific, anatomical, or botanical terminology to indicate a ring shape, a circular structure, or a ring-like arrangement of tissues or organs.