A Closer Look at Plant Classifications, Parts, and Uses
A CLOSER LoOK AT PLANT CLASSIFICATIONS PARTS AND USES The passion flower blossom family Passifloraceae displays a strik ing combination of sepals petals and stamens Shutterstock com help make the plant s food by collecting sunlight Stems give the plant support The roots anchor the plant to the ground draw water from the soil and store food Flowers seeds and fruits are part of the plant s repro ductive system With some 270 000 different kinds of plants in existence and possibly another
INTRODUCTION 30 000 that have yet to be identified these organisms play a significant role in our lives Cereals and grains are a major source of our nutrition and many livestock subsist on grains and grass as well Cotton is a source of material for clothing but did you know that synthetic fabrics like rayon are made from cellulose Paper comes from plants Many types of buildings and furniture are made from wood Cork rubber and even cocoa butter also come from trees Plants improve our atmosphere and provide us with fuel In addition plants of all kinds have been used in medicine Foxglove for example produces digitalis which helps treat heart disease Get ready to learn a lot about the incred ibly diverse world of plants These are complex fascinating organisms that we could not do without 9
CHAPTER 1 CHARACTERISTICs oF PLANTS W herever there is sunlight air and soil plants can be found On the northernmost coast of Greenland the Arctic poppy peeps out from beneath the ice Mosses and tussock grasses grow in Antarctica Flowers of vivid color and great variety force their way up through The Arctic poppy can bloom even under barren conditions Shutterstock com Io
CHARACTERISTICS OF PLANTS the snow on mountainsides Many shrubs and cacti thrive in deserts that go without rain for years at a time and rivers lakes and swamps are filled with water plants The scientists who study plants botanists have named and described approximately 270 000 different kinds of plants They estimate that another 30 000 unidentified species exist in less explored ecosystems such as tropical forests PLANTS AND THE BALANCE OF NATURE Plants are essential parts of ecosystems Most of the energy consumed in terrestrial ecosystems is provided by plants and as a consequence land animals are dependent on them for their food Plants absorb minerals such as potassium and phosphorus from the soil These are stored in plant tissues and are an essential part of the diet of animals that eat plants Plants help form enrich and sta bilize soil Hearty mosses help break down and crumble rock into soil The roots of trees and other plants also contribute to this process Decaying plant material such as leaves increases the fertility of soil Plant roots hold the soil in place and prevent erosion II
