Dichotomous Key for Leaves 1. Compound or simple leaf 1a) Compound leaf (leaf divided into leaflets) go to step 2 1b) Simple leaf (leat not divided into leaflets) go to step 4 2. Arrangement of leatlets 2a) Palmate arrangement of leaflets (leaflets all attached at one central point) Aesculus (buckeye) 2b) Pinnate arrangement of leaflets (leaflets attached at several points) go to step 3 3. Leaflet shape 3a) Leallets taper to pointed tips Carya (pecan) 3b) Oval leaflets with rounded tips Robinia (locust) 4. Arrangement of leat veins 4a) Veins branch out from one central point go to step 5 4b) Veins branch off main vein in the middle of the leat. 5. Overall shape of leaf go to step 6 5a) Leat is heart-shaped.. Cercis (redbud) 5b) Leat is star-shaped VII Liquidambar (sweet gum) 6. Appearance of leat edge 6a) Leaf has toothed (jagged) edge Betula (birch) 6b) Leaf has untoothed (smooth) edge Magnolia (magnolla)

An organism's environment is the environment in which it lives and has an impact on its well-being. The World Health Organization (WHO) defines environmental health as "those aspects of public health, such as quality of life, that are influenced by physi…