#photosynthesis

• Aphylly — The biological state, trait, or evolutionary phenomenon consisting of the complete, congenital, or adaptive absence of leaves in a plant or vegetative organ; it represents a major xerophytic modification optimized to minimize water loss.
• Allochlorophyll — An isomeric form of chlorophyll, obtained artificially or arising through minor chemical and structural alteration of the natural green pigment in plant or algal cells. This organic compound retains its basic properties in capturing the light spectrum, but exhibits modifications in the molecular structure of the porphyrin ring, being studied in plant physiology laboratories to understand the stability of the photosynthesis process.
• Alga — A lower, cryptogamic thallophyte plant with a body unsegmented into true roots, stems, or leaves, containing chlorophyll and other photosynthetic pigments. It lives primarily in aquatic environments or high-humidity spots. Classified into green, brown, or red variants, it plays a vital role in global ecosystems.
• Autotroph — A living organism capable of synthesizing its own organic substances required for nutrition and growth from simple inorganic compounds (such as carbon dioxide and water), utilizing an external energy source. Depending on the origin of the energy used, these organisms are classified into photoautotrophs, which use sunlight through photosynthesis (green plants, algae), and chemoautotrophs, which utilize chemical energy resulting from the oxidation of mineral substances.
• Autotrophic — Pertaining or relating to autotrophy; specific to the autonomous nutritional mode based on the synthesis of organic substances from inorganic compounds. This structural attribute describes metabolic processes, enzymatic systems, or cellular growth phases where external energy is chemically stored without dependency on other living organisms.
• Autotrophy — The property, quality, or way of life of autotrophic organisms, characterized by the physiological capacity to synthesize their own organic substances required for nutrition and growth from simple inorganic compounds, utilizing an external energy source (light or chemical). This phenomenon represents the energetic foundation of most terrestrial and aquatic ecosystems, ensuring carbon fixation in the biosphere.
• Bacteriochlorophyll — A tetrapyrrolic photosynthetic pigment, structurally related to the chlorophyll of green plants, present in anoxygenical phototrophic bacteria (such as purple and green sulfur bacteria). Biochemically, bacteriochlorophyll absorbs light in the near-infrared wavelength ranges, allowing photosynthesis to occur without producing oxygen in deep aquatic environments or dark sediments.