A Closer Look at Plant Classifications, Parts, and Uses
The next time you eat breakfast take a good look at the food on the table Juice from an orange buckwheat and blueberries in your pancakes sweet maple syrup drizzled on top and cocoa in your hot chocolate all these items come from plants In this book you will learn about what defines a plant and the different kinds of plants You will learn about the parts of a plant right down to its cells and tissues and discover many uses of plants in our daily lives So what is a plant Sure we know that a maple tree is a kind of plant and a fish is not but botanists scientists who study plants continue to debate the exact definition For years scientists deemed an organism a plant if it had green pigment could synthesize its own food with light and was not mobile All other organisms were regarded as part of the animal kingdom Closer studies of certain so called plants revealed that they were not all that similar to plants and had a vastly different evolution One basic characteristic of plants is that they are multicellular organisms that perform photosynthesis Another is that the cell walls of plant cells contain a stiffening material known as cellulose which makes tree trunks A
INTRODUCTION and twigs rigid Plants are also recognized as eukaryotes which means that their cells have a nucleus Plants are commonly organized by how they grow Trees shrubs and herbs each grow differently and take distinct forms Flowering plants can also be divided into a trio of classes based on their life cycle and growth pattern Annuals complete their life cycle in one year whereas biennials need two years Perennials grow for more thant two years Finally plants can be grouped accord ing to their complexity Nonvascular plants include liverworts hornworts and mosses Seedless vascular plants include ferns and their relatives Among vascular seed plants are conifers and flowering plants Cells make up every living thing and in plants the cells come together to form tis sues Simple plant tissues or ground tissues are made up of only one type of cells Simple tissues include parenchyma collenchyma and sclerenchyma tissues Complex tissues dermal and vascular are composed of two or more types of cells At first glance plants might seem like pretty simple organisms but further study reveals how complex they can be Leaves
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
