Plant I.D. & monocots & dicots

                                             GENERAL BOTANY  Lecture Note.  Plant I.D. & monocots & dicots

 

I.              Plant identification

                A.            Phylogenic (natural) system

                                1.             Kingdom

                                2.             Phylum

                                3.             Class

                                4.             Order

                                5.             Family

                                6.             Genus

                                7.             Species

                Example:  Redbud - Plantae (plants), Anthophyta / Magnoliophyta (flowering), Magnoliopsida (dicots), Rosales (roses), Leguminosae (legumes), Cercis, canadensis

II.            Special features of angiosperms - monocots and dicots

                A.            Dicotyledonae (Magnoliopsida)

                                1.             "Two cotyledons in seed"

                                2.             Broadleaf plants

                                3.             Netlike leaf veins - xylem and phloem

                                4.             Two leaf parts (sometimes three)

                                                a)             Blade (leaf)

                                                b)             Petiole - pelate (attaches to middle) and sessile (direct attachment)

                                                                1)            Extends the leaf

                                                                2)            Allows leaf to move

                                                c)             Stipule - at base of petiole

5.                   Flower parts usually come in units of four or five

6.                   Taproot system with one or more primary roots from which secondary roots develop

                B.            Monocotyledonae (Liliopsida)

                                1.             "One cotyledon in seed"

                                2.             Long, grasslike leaves

                                3.             Parallel leaf veins

                                4.             Two leaf parts (sometimes up to four)

                                                a)             Blade

                                                b)             sheath - covers stem

                                                c)             ligule - keeps water from between stem and sheath

                                                d)             auricle - forms a collar at base of blade

                                5.             Flower parts usually come in units of three

                                6.             Grass flowers (among monocots) are often incomplete or inconspicuous

                                                a)             Lacking or not showing sepals or petals

                                7.             Fibrous root systems