Lamiaceae

Lamina

The lamina is the flattened portion of the leaf.  Lamina is synonymous with blade.

                    DIAGRAM:  Leaf Cross Section / Leaf Cross Section

                          PHOTO:  Leaf Cross Section / Leaf Cross Section / Leaf Cross Section
                                           Leaf Cross Section / Leaf Cross Section / Leaf Cross Section

                                           Fern Leaf Cross Section

Land Bridges

Landscape

Larch

Lateral

Lateral Buds

Lateral buds are dormant buds found at a node that will grow into a stem when they break dormancy.

                    DIAGRAM:  lateral bud

                          PHOTO:  

Lateral Roots

                    DIAGRAM:  Root Anatomy

                          PHOTO:  

Lateral Shoot

                    DIAGRAM:  Woody Dicot Stem Morphology

                          PHOTO:  

Lateral Transport

Lateral transport is transport of food products, water, and minerals out to the margin of the stem. Lateral transport as compared with axial transport is that axial transport is vertical and lateral transport is horizontal.

Lateral Vein

                    DIAGRAM:  Leaf Cross Section

                          PHOTO:  Leaf Cross Section / Fern Leaf Cross Section

Latitude

Latin

Laws of Thermodynamics

Leaching

Leaf

                    DIAGRAM:  Leaf Cross Section / Leaf Cross Section

                          PHOTO:  Leaf Cross Section / Leaf Cross Section / Leaf Cross Section
                                           Leaf Cross Section / Leaf Cross Section / Leaf Cross Section

                                           Fern Leaf Cross Section

Leaf Abscission

Leaf Apex

The leaf apex is the shape of the upper tip of the leaf lamina (the end opposite the petiole).

                    DIAGRAM:  Leaf Apex

                          PHOTO:  

Leaf Axil

                    DIAGRAM:  Leaf Axil

                          PHOTO:  

Leaf Base

A leaf base is the shape of the leaf lamina at its base.  As a general rule, this is where the petiole attaches to the lamina.

                    DIAGRAM:  Leaf Bases

                          PHOTO:  

Leaf Buds

Leaf buds are buds that develop into leaves when the weather becomes warm enough in the spring.

Leaf Initial

Leaf Primordia

Leaf primordia are structures that are formed on the flanks (outer margin) of the apical meristem. These are the first cells that aggregate to form the beginnings of a future leaf.

                    DIAGRAM:  Leaf Primordium

                          PHOTO:  

Leaf Scars

Leaf scars are places on the stem where leaves used to be.  Because leaves only live for a short time (usually one to five years) they are shed by the plant.  When the leaf drops off it leaves a scar.  The outline of that scar can be seen at the node.  Within the outline of the leaf scar there will be bundle scars, the scars of the old vascular bundles that attached the leaf's vascular system to that of the plant.

                    DIAGRAM:  Woody Dicot Stem Morphology
                                           Leaf Scar

                          PHOTO:  

Leaf Vein

                    DIAGRAM:  Sclerid

                          PHOTO:  

Leaflet

Leaflets are the laminas of a compound leaf.  Simple leaves contain only one lamina while compound leaves contain many lamina.  Leaflets describe these many lamina of a compound leaf.

Legumes

Lemmings

Lemon

Lenticels

Lenticels are small places where the bark is pushed up in a lose fashion so that air can get to the cells of the stem for the purpose of respiration.

Lenticels

                    DIAGRAM:  Woody Dicot Stem Morphology

                          PHOTO:  

Lettuce

Leucosin

Lichens

Light

Light Quality

Light Intensity

Lignin

Lignin is embedded in the secondary wall of plant cells that are dead when functioning.  Lignin typically stains red in prepared microscope slides.  Fibers, sclerids, vessels, and tracheids are cells that contain lignin.

Ligule

Ligule literally means tongue.  It is typically a small flap of plant tissue that is tougue-shaped. In grass leaves, it is a short extension of the sheath above the blade.

                    DIAGRAM:  Grass Leaf Structure

                          PHOTO:  Selaginella Strobilus Longitudinal Section
                                           Selaginella Strobilus Longitudinal Section
                                           Selaginella Strobilus Longitudinal Section

                                           Composite Flower / Composite Flower / Composite Flower
                                           Composite Flower / Composite Flower

Like Charges

Like Molecules

Liliaceae

                    DIAGRAM:  Liliaceae

                          PHOTO:  

Lilies

Lime

Limiting Factors

Limnetic Zone

Lions

Lipid Droplets

                    DIAGRAM:  Chloroplast

                          PHOTO:

Lipopolysaccharide

Lipoprotein

Liquid

Lithosphere

Littoral Zone

Liverworts

Lizards

Lobed Ovary

Lobes

Lobsters

Locomotion

Locule

                    DIAGRAM:  

                          PHOTO:  Narcissus

Long-day Plants

Longitude

Low Concentrations

(hormones)

Lower Lip

Lumen

The lumen is the opening or cavity of a cell that contains all the living material in the plant cell. The lumens cavity is produced by the cellulose of the cell wall.

                    DIAGRAM:  Sclerid

                          PHOTO:  

Luminating Organs

Lycophyta

Lycopodium

Lycopodium is a genus in the group of plants known commonly as the club mosses.  These are tracheophytes that are in the division Lycophyta characterized by containing short side branches off the main rhizome.  At the tip of the branches are a cluster of sporophylls that produce spores. This cluster of sporophylls is termed a strobilus.  Lycopodium is homosporous.

                    DIAGRAM:  

                          PHOTO:  Lycopodium Strobilus Longitudinal Section

Lynx

Lysosome

                    DIAGRAM:  Golgi Complex

                          PHOTO:  

Lysozymes