Chapter 2: Terms
Here are the terms from this week’s lessons that you will need to be familiar with for your assignments and for the quiz.
| Binomial nomenclature | System of naming in which two terms are used to denote a species of living organism, the first indicating the Genus and the second the Specific Epithet. |
| Class | Taxonomic rank below Division and above Order. |
| Cotyledonary node | Food storage structure used in germination. |
| Dicotyledon | Seed plant that produces an embryo with paired cotyledons, floral organs arranged in cycles of four or five, and leaves with net-like veins. |
| Division | Second highest taxonomic category, consisting of one or more related classes, and corresponding approximately to a Phylum in zoological classification. |
| Emergence | Germination, when the embryo becomes active and the radicle grows through the seed coat. |
| Epicotyl | Portion of the stem of a seedling or embryo located between the cotyledons and the first true leaves. |
| Epigeal | Type of seedling emergence where cell division in the hypocotyl is initially more active and rapid than cell division in the epicotyl. Cotyledons are brought above the soil surface as the hypocotyl expands. |
| Family | Taxonomic rank below Order and above Genus. |
| Genotype | Genetic composition of an organism. |
| Genus | Group of species possessing fundamental traits in common but differing in other lesser characteristics; taxonomic rank below Family and above Specific Epithet. |
| Hierarchy | System of grouping where each classification is a subset of a superior grouping, and may contain subordinate categories. |
| Hypocotyl | Embryonic shoot below the cotyledons. |
| Hypogeal | Type of seedling emergence where the cotyledons remain below the surface of the ground. |
| Nomenclature | Formal system of names attached to the taxonomic groupings. |
| Order | Taxonomic rank below Class and above Family. |
| Phenotype | Physical appearance of an organism. |
| Phylum | Taxonomic rank below Kingdom and above Class; used in zoological classification. |
| Radicle | Embryonic root that breaks through the seed coat during germination and develops into the seedling’s root system. |
| Seed | Ripened ovule containing a seed covering, food storage, and an embryo. |
| Seed coat | Outer layer of the seed. |
| Seed germination | Activation of metabolic pathways of the embryo leading to the emergence of a new seedling. |
| Specific epithet | Uncapitalized Latin adjective or noun that follows a capitalized Genus name in binomial nomenclature and serves to distinguish a species from others in the same genus, as saccharum in Acer saccharum (sugar maple). |
| Taxonomy | Science of classifying organisms. |
