BCS Written Botany key terms

A localized region of dividing cells at the tips of roots and shoots that produces new cells for primary growth, giving rise to the primary plant body.

A cylindrical sheath of dividing cells, such as vascular cambium and cork cambium, that produces secondary tissues and increases the girth of stems and roots.

Growth in length resulting from cell division and elongation in apical meristems, producing the primary tissues of roots, stems, and leaves.

Growth in thickness resulting from the activity of lateral meristems, which add secondary xylem and phloem and produce wood and bark in woody plants.

A lateral meristem forming a continuous ring of dividing cells between xylem and phloem; it produces secondary xylem inward and secondary phloem outward.

The system of naming species with two Latinized parts, genus and specific epithet, governed by international codes and giving each species a unique scientific name.

The single preserved specimen designated by the original author as the permanent reference for a new species name, against which other specimens are compared.

A method of phylogenetic classification that groups organisms based on shared derived characters, recognizing only monophyletic groups and depicting relationships as branching diagrams.

A group consisting of an ancestor and all of its descendants, also called a clade, representing a complete branch of the evolutionary tree.

Any named taxonomic unit at any rank, such as a species, genus, family, or order, used in classification and nomenclature.

The loss of water vapor from aerial plant parts, mainly through stomata, which drives water uptake and creates tension in the xylem.

The explanation that water moves upward in xylem because transpiration creates negative pressure, and cohesion between water molecules transmits the pull from leaves to roots.

The potential energy of water per unit volume relative to pure water at atmospheric pressure; water moves from higher to lower water potential, driving osmosis and cell expansion.

The pressure exerted by the protoplast against the cell wall due to water uptake, providing mechanical support and driving cell enlargement in growing plant tissues.

The light-driven process in chloroplasts that converts carbon dioxide and water into organic compounds, releasing oxygen and storing energy in chemical bonds.

The light-independent series of reactions in chloroplast stroma that fixes carbon dioxide and reduces it to sugar using ATP and NADPH from the light reactions.

A green pigment in chloroplasts that absorbs light energy and initiates the light reactions of photosynthesis by exciting electrons.

The process of nuclear division that produces two genetically identical daughter nuclei, essential for growth and asexual reproduction in plants.

A specialized cell division that halves the chromosome number and generates genetic variation through crossing over and independent assortment, producing spores or gametes.

The exchange of genetic material between homologous chromosomes during prophase I of meiosis, creating new combinations of alleles on chromosomes.

The ordered sequence of events from one cell division to the next, comprising interphase and the mitotic phase, tightly regulated by checkpoints and cyclins.

A protein catalyst that accelerates biochemical reactions by lowering activation energy, often showing specificity for substrates and sensitivity to temperature and pH.

The process by which information in a gene directs the synthesis of a functional product, usually a protein, through transcription and translation.

The synthesis of an RNA molecule from a DNA template, catalyzed by RNA polymerase, forming messenger RNA or other functional RNAs.

The process in which ribosomes use messenger RNA to assemble amino acids into a polypeptide chain according to the genetic code.

A laboratory technique that amplifies a specific DNA segment through repeated cycles of denaturation, primer annealing, and extension by a thermostable DNA polymerase.

A microorganism lacking a membrane-bound nucleus and organelles, with circular DNA, represented by bacteria and archaea.

An organism whose cells contain a membrane-bound nucleus and organelles, including plants, animals, fungi, and protists.

A single-celled prokaryotic microorganism, typically with a cell wall, that can be beneficial, pathogenic, or involved in nutrient cycling.

A symbiotic association between a fungus and plant roots in which the fungus enhances water and nutrient uptake, especially phosphorus, in exchange for carbohydrates.

An organism, such as a fungus, bacterium, virus, or nematode, that causes disease in a host plant by colonizing its tissues and disrupting normal functions.

A close and prolonged association between two different organisms, which may be mutualistic, commensal, or parasitic, affecting the survival of both partners.

A life cycle in which a multicellular haploid gametophyte phase alternates with a multicellular diploid sporophyte phase, characteristic of plants and some algae.

The haploid, gamete-producing phase of a plant life cycle, which develops from a spore and produces gametes by mitosis.

The diploid, spore-producing phase of a plant life cycle, which develops from a zygote and produces haploid spores by meiosis.

A dynamic community of living organisms interacting with one another and with their physical environment, through which energy flows and nutrients cycle.

The variety of life at genetic, species, and ecosystem levels, essential for ecosystem stability and providing goods and services to humanity.

Development that meets present needs without compromising the ability of future generations to meet theirs, balancing economic, social, and environmental goals.

The aseptic growth of plant cells, tissues, or organs on nutrient media under controlled conditions, used for micropropagation and genetic improvement.

The rapid asexual production of large numbers of genetically identical plants from small tissue explants using in vitro culture techniques.

The introduction of foreign DNA into a plant genome using methods such as Agrobacterium-mediated transfer or biolistics, producing transgenic plants with new traits.

A testable, falsifiable statement proposing a relationship between variables, forming the basis for experimental design and statistical analysis in research.

The planned arrangement of treatments, controls, and replication in an experiment to ensure valid, unbiased, and statistically analyzable results.

A result unlikely to have occurred by chance alone, conventionally assessed by a p-value below a chosen threshold, supporting rejection of the null hypothesis.