The Cell

Published in 2011 by Britannica Educational Publishing (a trademark of Encyclopædia Britannica, Inc.) in association with Rosen Educational Services, LLC 29 East 21st Street, New York, NY 10010. Copyright © 2011 Encyclopædia Britannica, Inc. Britannica, Encyclopædia Britannica, and the Thistle logo are registered trademarks of Encyclopædia Britannica, Inc. All rights reserved. Rosen Educational Services materials copyright © 2011 Rosen Educational Services, LLC. All rights reserved. Distributed exclusively by Rosen Educational Services. For a listing of additional Britannica Educational Publishing titles, call toll free (800) 237-9932. First Edition Britannica Educational Publishing Michael I. Levy: Executive Editor J.E. Luebering: Senior Manager Marilyn L. Barton: Senior Coordinator, Production Control Steven Bosco: Director, Editorial Technologies Lisa S. Braucher: Senior Producer and Data Editor Yvette Charboneau: Senior Copy Editor Kathy Nakamura: Manager, Media Acquisition Kara Rogers: Senior Editor, Biomedical Sciences Rosen Educational Services Heather M. Moore Niver: Editor Nelson Sá: Art Director Cindy Reiman: Photography Manager Matthew Cauli: Designer, Cover Design Introduction by Smriti Jacob Library of Congress Cataloging-in-Publication Data The cell / edited by Kara Rogers, in association with Britannica Educational Publishing, Rosen Educational Services.—1st ed. p. cm.—(Biochemistry, cells, and life) “In association with Britannica Educational Publishing, Rosen Educational Services.” Includes bibliographical references and index. ISBN 978-1-61530-386-1 (eBook) 1. Cells—Popular works. I. Rogers, Kara. II. Series: Biochemistry, cells, and life. [DNLM: 1. Cells. 2. Cell Physiological Phenomena—physiology. QU 300 C3928 2011] QH582.4.C42 2011 571.6—dc22 2010019441 On the cover: Blood cells are just one of more than 200 different types of cells that make up humans and other mammals. © www.istockphoto.com/Bogdan Pop On page x: Bacteria are good examples of prokaryotes, organisms that do not have an overt nucleus or other organelles because they lack internal membranes. Dr. Terrence Beveridge/ Visuals Unlimited/Getty Images On pages 1, 30, 61, 104, 134, 164, 198, 201, 203: Blue-green algae such as cyanobacteria descend from the first prokaryotes that could photosynthesize with only water as an electron donor and produce molecular oxygen. Dr. Peter Siver/Visuals Unlimited/Getty Images CONTENTS Introduction x 13 chapter 1: the nature, function, and evolution of cells 1 Eukaryotes and Prokaryotes 2 The Organization of Cells 3 The Molecules of Cells 4 Robert Hooke 5 Albert Claude 6 The Structure of Biological Molecules 7 Approximate Chemical Composition of a Typical Mammalian Cell 8 Coupled Chemical Reactions 9 The Genetic Information of Cells 15 DNA: The Genetic Material 15 RNA: Replicated From DNA 17 Cells and Tissues 19 Animal Tissues 19 Plant Tissues 21 The Evolution of Cells 22 The Development of Genetic Information 23 The Development of Metabolism 26 Evolutionary Origins of Mitochondria and Chloroplasts 28 chapter 2: cell membranes and cell Walls 30 The Cell Membrane 30 Chemical Composition and Membrane Structure 31 Transport Across the Membrane 35 Jens C. Skou 47 Élie Metchnikoff 52 The Cell Walls of Plants 53 Charles-François Brisseau de Mirbel 55 54 69 88 Mechanical Properties of Wall Layers 55 Components of the Cell Wall 56 chapter 3: cellular organelles 61 The Relative Volumes Occupied by Some Cellular Compartments in a Typical Liver Cell 61 Internal Membranes 63 General Functions and Characteristics of Organelle Membranes 64 The Nucleus 66 DNA Packaging in the Nucleus 67 Nucleosomes: The Subunits of Chromatin 68 Organization of Chromatin Fibre 69 The Nuclear Envelope 70 Genetic Organization of the Nucleus 70 Roger D. Kornberg 76 Mitochondria and Chloroplasts 78 Mitocho