Anatomy of Zea Mays By Amy Peterson IB 423

Fast Corn Facts Native of Southern Mexico Grows over 2.5 m (8 feet) C4 plant with a Kranz anatomical structure Monocot Grass An ear of corn averages 800 kernels in 16 rows Iowa, Illinois, Nebraska and Minnesota account for over 50 percent of the corn grown in the U.S

The Many Faces of Corn Insecticides Latex paint Shaving cream & lotions Toothpaste Check out http://www.ontariocorn.org/classroom/products.html for a zillion uses for corn! As author Margaret Visser put it in her book, "Much Depends on Dinner," "You cannot buy anything at all in a North American supermarket which has been untouched by corn…"

Starting with the Root. . . Fibrous root system Coleoptile Methylene Blue X4 Coleoptile Coleoptile- Sheath coming from the embryo interpreted as the first leaf of the epicotyl

Closed Root Apical Meristem Distinct Root Cap Meristem Calyptrogen Root Cap Protoderm Region of Initials Zone of Elongation Closed Root Apical Meristem Distinct Root Cap Meristem called Calyptrogen Water X4 Simmons ©

POLYARCH VASCULAR BUNDLE ARRANGEMENT Water X4 ATRICHOBLAST PERICYLE PHLOEM XYLEM ENDODERMIS CORTEX Water x10 ROOTHAIR TRICHOBLAST

Branch Roots Pith Cortex Parenchyma pith Branch Root Methylene Blue X4 Water X4 Branch Root Methylene Blue X4

MOVING UP TO THE STEM… Scattered Vascular Bundles Xylem Water X4 Water X10 Water X10 Xylem Curled Leaf attached to main stem

VASCULAR TISSUE Tylose Ray Sieve Plate Xylem Metaxylem Phloem Methylene Blue X40 VASCULAR TISSUE Tylose Ray Sieve Plate Xylem Metaxylem Phloem Sieve Tube Member Methylene Blue X20 Methylene Blue X20 Parenchyma

The xylem and phloem do not just go straight up and down but actually meet at nodes up the stem. Here are some pictures of intersections, where vascular bundles are both seen longitudinally and in cross section Methylene Blue X4 Longitudinal Section! Methylene Blue X20 Cross Section Methylene Blue X10 Cross Section

Emerging Leaf and Shoot Apical Meristem Corpus Tunica Emerging Leaf Water X4 Stem Leaf Primordia Shoot Apical Meristem Webb ©

AND SHIFTING OVER TO THE LEAVES... Parallel Venation Xylem Methylene Blue X10 Bundle Sheath Commisural Veins

Collenchyma Metaxylem Phloem Sclerenchyma Lacuna Protoxylem Methylene Blue X10 Leafs are layered around the stem Water X20 Sclerenchyma Lacuna Protoxylem Methylene Blue X10 Bulliform Cells

Leaf Trace A distichous arrangement Leaf Trace Methylene Blue X20

Stomata IV-2 Lapaseria Rosea arrangement Amphistomatic Bifacial Water X10 Stomates Peel X20 IV-2 Lapaseria Rosea arrangement Amphistomatic Bifacial

REPRODUCTION Lower part of embryo axis is a radicle Coleoriza is a sheath that encloses radicle Plumule is the embryotic shoot Endosperm Cotyledon Cotyledon (Scutellum) Plumule Shoot Apex Root (Radicle) Coleoriza Same thing in XS

STARCH Starch concentrated in seeds, like these in corn kernels Stained with IKI IKI X20 Arise from plastids Typical starch grain shape/appearance IKI X10

Tassels Male Reproductive Structure Each tassel consists of a floret with three stamens Water X10 Monoecious Self and cross-pollinating Water X10

BIBLIOGRAPHY Crang, Richard and Andrew Vassilyev. Plant Anatomy. McGraw-Hill. Dickison, William. Integrative Plant Anatomy. Boston: Academic Press, 2000. Esau, Katherine. Anatomy of Seed Plants. New York: John Wiley and Sons, 1977. Esau, Katherine. Plant Anatomy. New York: John Wiley and Sons, 1967. Hochholdinger, Frank. 03/25/2004. Genetic analysis of Root Formation in Zea Mays. University of Tübingen. 04/25/2005 <http://www.unituebingen.de/ZMBP/research/gghochholdinger.html>. Sengbusch, Peter V. Root Tip of Zea Mays. University of Hamburg. 04/25/2005 <www.biologie.uni-hamburg.de/b-online/e40/wurzel.htm>. Simmons, Kent. Internal Anatomy of Roots. University of Winnepeg. 04/27/2005 <www. http://io.uwinnipeg.ca/~simmons/2153/lb3pg4.htm>. Webb, David T. Vegetative Features. University of Hawaii at Manoa. 04/25/2005 <http://www.botany.hawaii.edu/faculty/webb/>.