CHAPTER 37 VEGETATIVE PLANT DEVELOPMENT By Rebecca Andrus & Michelle Armendariz Seeds A seed leaf that generally stores food in dicots or monocots Nourishes during germination Cotyledon Storage tissue characteristic of the seeds of angiosperms Endosperm Outer layer of ovule; relative barrier to protect dormant embryo and stored food Seed Coat Why are seeds beneficial? 1.) They maintain dormant in unfavorable conditions; postpone development until there are better conditions. 2.) Afford maximum protection to young plants at their most vulnerable stage of development. 3.) Contain stored food that allows plant to grow & develop before photosynthesis begins. 4.) Facilitate the migration of the plant genotypes into new habitats. Germination Oxygen and water must reach the embryo in order for germination to take place. The resumption of growth and development by spore or seed. Germination Ways Fruits Help With Dispersal 1. Fruits with fleshy coverings get carried by birds or other vertebrates Ex) red rose 2. Fruits with hooked spines hitch a ride on fur or human clothing Ex) stick tights 3. Fruits with wings are distributed by the wind Ex) maple 4. Fruits around beaches get distributed by water Ex) cocunuts Kinds of Fruits Fruits: mature ripened ovary or group of ovaries containing the seeds True berries Drupes Aggregate fruits Legumes Samaras Multiple fruits Single seed enclosed in a hard pit. Multiple seeds, fleshy pericarp. Split along two carpel edges with seeds attached to edges. Individual flowers from fruits around single stem. Not split with a wing made from outer tissues. Many ovaries of a single flower. Signals from Environment that Plants Wait for to Start Germination Light of correct wave length & intensity Series of cold days Passage of time at temperatures appropriate for germination Scutellum Where nutrients are stored that are needed for germination.