A Closer Look at Plant Reproduction, Growth, and Ecology
CONTENTS INTRODUCTION CHAPTER METHODS OF PLANT REPRODUCTION 10 CHAPTER PLANT GROWTH AND DEVELOPMENT 22 CHAPTER INFLUENCES ON PLANT GROWTH 39 CHAPTER PLANT ECOLOGY 50 74 75 CONCLUSION GoSSARY For MORE INFORMATION BIBLIOGRAPHY 78 INDEX 83
O n many ways plants are like any other living organism A plant is born grows levelops reproduces and like animals and humans plays a vital role in sustaining the environment in which it lives Yet there are also a number of life processes that set plants apart from other living things As this book details the habits and survival methods of plant life on Earth range from the simply curious to the truly remarkable Consider the ways in which plants reproduce Some plants are created by the joining of one parent plant's male sex cells and another's female sex cells Humans and most animals also reproduce in this way Yet there are other methods of plant reproduc tion that don't depend upon two parents or even sex cells for that matter Leaves and stems whether they break off on their own are cut on purpose or naturally grow under ground in the case of tubers and bulbs are capable of sprouting roots and giving birth to a new independent plant All living things depend on water for their survival This is especially true of plants The role of water in the life of a plant is a lot like that of blood in humans and animals water carries nutrients and other molecules
INTRODUCTION that keep plants alive There is no organ like a heart though to move water through a plant's system Instead plants rely on tran spiration and diffusion Transpiration is the process that allows water to reach all the cells throughout a plant Plants constantly lose water by sweating through tiny openings in their leaves This causes lower water concentrations in leaf cells The plant responds by drawing water from the soil into the roots and then up the stem to the leaves Once water reaches a cell it is drawn into the cell through diffusion The interiors of plant cells have high levels of salt and sugars In diffusion water molecules move from where they are plentiful outside cell membranes to where they are in short supply inside the cells No discussion of plant life would be com plete without mention of photosynthesis This is the process by which plants use sun light carbon dioxide water and minerals to create their own food Photosynthesis also benefits other living creatures including humans For one thing any organism that eats plants absorbs the nutrients that pho tosynthesis creates The benefits extend to other creatures that eat plant eaters in what
