Botany Glossary

A flowering plant that produces seeds enclosed within a fruit (mature ovary). The largest group of land plants with approximately 300,000 species.

A class of plant hormones that promote cell elongation, apical dominance, and tropisms.

The set of light-independent chemical reactions in photosynthesis that fix CO2 into organic molecules in the chloroplast stroma.

A lateral meristem that produces secondary xylem (wood) inward and secondary phloem outward, causing the stem or root to increase in diameter.

A structural polysaccharide composed of beta-glucose chains that forms the primary component of plant cell walls.

A double-membrane organelle in plant cells where photosynthesis occurs. Contains thylakoids (light reactions) and stroma (Calvin cycle).

An embryonic leaf within a seed. Monocots have one cotyledon; dicots have two. They store or absorb nutrients for the developing seedling.

A waxy, waterproof layer on the outer surface of the epidermis of leaves and stems that reduces water loss.

Nutritive tissue inside seeds of flowering plants that provides nourishment to the developing embryo.

The outermost layer of cells covering leaves, stems, and roots. It provides protection and regulates gas exchange via stomata.

A gaseous plant hormone involved in fruit ripening, leaf abscission, and stress responses.

A seed plant that bears naked seeds not enclosed in an ovary or fruit. Includes conifers, cycads, ginkgo, and gnetophytes.

A complex polymer deposited in cell walls that provides rigidity and waterproofing, particularly in xylem and sclerenchyma.

A region of undifferentiated, actively dividing cells that enables plant growth.

A mutualistic symbiotic association between a fungus and a plant root that enhances nutrient and water uptake.

A type of ground tissue consisting of thin-walled, loosely packed living cells involved in photosynthesis, storage, and tissue repair.

Vascular tissue that conducts sugars and organic compounds from photosynthetic tissues to other parts of the plant.

The physiological response of plants to the relative lengths of day and night, influencing flowering, dormancy, and other developmental processes.

The process by which green plants and other organisms use sunlight to synthesize glucose from carbon dioxide and water, releasing oxygen.

Microscopic grains containing the male gametophyte of seed plants, produced in the anthers of flowers or microsporangia of cones.

A genus of nitrogen-fixing bacteria that forms symbiotic nodules on the roots of legumes.

A microscopic pore in the leaf epidermis, flanked by guard cells, that controls gas exchange and transpiration.

The loss of water vapor from aerial parts of a plant, mainly through stomata, driving water uptake from the soil.

A directional growth response of a plant toward or away from an environmental stimulus such as light (phototropism) or gravity (gravitropism).

Vascular tissue composed of dead, lignified cells that transports water and dissolved minerals from roots to the rest of the plant.