Tài liệu Encyclopedia+of+biology

encyclopedia of Biology ENCYCLOPEDIA OF biology don rittner Timothy and L. McCabe, Ph.D. Encyclopedia of Biology Copyright © 2004 by Don Rittner All rights reserved. No part of this book may be reproduced or utilized in any form or by any means, electronic or mechanical, including photocopying, recording, or by any information storage or retrieval systems, without permission in writing from the publisher. For information contact: Facts On File, Inc. 132 West 31st Street New York NY 10001 Library of Congress Cataloging-in-Publication Data Rittner, Don. Encyclopedia of biology / Don Rittner and Timothy L. McCabe. p. cm. Summary: Contains approximately 800 alphabetical entries, prose essays on important topics, line illustrations, and black-and-white photographs. Includes bibliographical references (p. ). ISBN 0-8160-4859-2 1. Biology—Encyclopedias, Juvenile. [1. Biology—Encyclopedias. 2. Encyclopedias and dictionaries.] I. McCabe, Timothy Lee. II. Title. QH309.2.R58 2004 570’.3—dc222003021279 Facts On File books are available at special discounts when purchased in bulk quantities for businesses, associations, institutions, or sales promotions. Please call our Special Sales Department in New York at (212) 967-8800 or (800) 322-8755. You can find Facts On File on the World Wide Web at http://www.factsonfile.com Text design by Joan M. Toro Cover design by Cathy Rincon Illustrations by Richard Garratt and Sholto Ainslie Printed in the United States of America VB FOF 10 9 8 7 6 5 4 3 2 1 This book is printed on acid-free paper. Dedicated to Louis F. Ismay and John F. Roach Two superb teachers who taught me to always ask why and to my family Nancy, Christopher, Kevin, Jackson, Jennifer, & Jason CONTENTS Acknowledgments ix Preface xi Introduction xiii Entries A–Z 1 Feature Essays: “Blood Identification through the Ages” by John C. Brenner and Demetra Xythalis 44 “Human Cytogenetics: Historical Overview and Latest Developments” by Betty Harrison 67 “The Karner Blue—New York’s Endangered Butterfly” by Robert Dirig 111 “Insects and Man—An Exotic Dilemma” by Timothy L. McCabe, Ph.D. 158 “Science and the Spiritual Factor” by John McConnell 170 “Silk Degrees: A Tale of Moths and People, Part One” by James G. (Spider) Barbour 200 “Sassafras and Its Lepidopteran Cohorts, or Bigger and Better Caterpillars through Chemistry” by Timothy L. McCabe, Ph.D. 202 “Silk Degrees: A Tale of Moths and People, Part Two” by James G. (Spider) Barbour 228 “Egyptian Mummies: Brief History and Radiological Studies” by William A. Wagle, M.D. 233 Appendixes: Appendix I Bibliography 357 Appendix II Biology-Related Websites 363 Appendix III Biology Software and Animations Sources 365 Appendix IV Nobel Laureates Relating to Biology 367 Appendix V Periodic Table of the Elements 377 Appendix VI Biochemical Cycles 379 Appendix VII The “Tree of Life” 381 Index 383 ACKNOWLEDGMENTS We would like to thank the following for their generosity in helping to make this book as complete as possible, especially in the use of images, biographies, essays, and encouragement: Darryl Leja, NHGRI, National Institutes of Health, for wonderful illustrations; Marissa Mills, Human Genome Management Information System, Oak Ridge National Laboratory, U.S. Department of Energy Genomes to Life Program; Celia Boyer, executive director, Health On the Net (HON) Foundation; Kristina Fallenias, Nobel Foundation; Fabienne Meyers, International Union of Pure and Applied Chemistry; Robert Dirig, Cornell University; Centers for Disease Control; William and Greta Wagle; John McConnell; John C. Brenner; Demetra Xythalis; Joseph Deuel, Petrified Sea Gardens, Inc.; Betty Harrison; James G. (Spider) Barbour; Hideki Horikami; Thomas Wittling; and to Nancy, Chris, Kevin, and Jack. Finally, thanks to Frank K. Darmstadt, our very patient editor, and the rest of the staff at Facts On File for their contributions. We apologize to anyone left out in error. ix PREFACE Despite the often extreme specialization and intimate knowledge required to make a contribution to science, most scientific disciplines are quick to adapt new technologies and advances developed from other fields. Inevitably, a new vocabulary follows these advances, the purpose of which is to convey meaning with a word that once required a descriptive paragraph or even a page. The Encyclopedia of Biology pulls together the specialized terminology that has found its way into the language of the biologist. It addresses the often duplicitous meanings in an easily understood, succinct fashion. As each discipline has become more of a specialty, each has developed terms that serve as a shorthand for concepts within that discipline. On rare occasion, different disciplines develop the same term with radically different definitions. By indicating a discipline, the encyclopedia directs the reader to a definition relevant to the topic at hand. An example of this is the word genotype. Historically, this was a taxonomist’s term meaning “the type of the genus.” The genotype is important for classification and evolutionary studies. Subsequently, geneticists used genotype to refer to the genetic makeup of an organism. One needs to understand not only the meaning of words, but must also be able to put them in the context of the period in which they were written. There will be new terms, new (and defunct) science Websites, new leaders, new disciplines, and even breathtaking new discoveries in science, but these will not detract from the utility of this encyclopedia. Bibliophiles need only pause to consider which books they consult most frequently. The reference book holds counsel over all others. Facts On File’s Encyclopedia of Biology may not read like a novel, but it will help you read like a biologist. —Tim McCabe, Ph.D. xi INTRODUCTION Facts On File’s Encyclopedia of Biology is a reference to help in understanding the basic concepts in biology and its peripheral disciplines like ecology, botany, and even Earth science. Arranged in alphabetical order, the entries include biographies of individuals who have made major contributions as well as numerous line illustrations and photographs to help in visualizing technical concepts. I have tried to include the more common terms you will likely encounter during your educational experience or even when you are out in the “real” world. There are literally thousands of biological terms. Many are so specific to major or minor subdisciplines of biology that you may never encounter them. You will not find those esoteric terms in this encyclopedia but, rather, a collection of terms that you should be familiar with to understand core biological principles and have a working knowledge of the field. You can also use this volume simply to increase your scientific vocabulary. A series of well-placed essays elaborate on some of the most important trends and issues in the field. One of these describes how the use of computer technology has revealed an artificial toe in a mummy that is thousands of years old. You will also learn how blood is used in forensic science to capture criminals and read about the latest trends in human cytogenetics. Other essays will make you think about your role in the world and explore some of the negative effects we humans have had on the biological world, in particular to the insect family. The encyclopedia also includes appendixes with information about Internet Websites and biology-related software that is waiting for you to explore. We humans are part of this immense biological world, and we interact with it in many ways. Some of those interactions have cost species their very existence. Some have helped us survive disease. In other cases, we have helped species come back from the brink of extinction. This complex interrelationship is not clearly understood even today, and that is why many who use this book are pursuing some aspect of biology as a career. We have come a long way from Robert Hooke’s first observation of a cell under a crude microscope to today’s observations of atomic-level activity using electron microscopes. The use of computer science and technology has enabled huge leaps in our understanding of our biological xiii xiv Introduction world. The future hope of nanotechnology, using small robots to scurry through our bodies to fix organs or cure disease, is closer to becoming reality than it is to fiction. Other former sci-fi issues, like cloning humans, are on the forefront of discussion, and some have even claimed human cloning has happened. The mapping of our entire genetic makeup brings promise to thousands of people who have or carry genetically based disease. This has led at least one scientist to declare that we are moving into the “industrial revolution of biology,” anticipating the exciting discoveries just around the corner from the analysis of all this genetic information. We are entering a world of molecular understanding of developmental biology all the way to the enigma of consciousness. But you cannot leap without first taking small steps. Use this book for the small steps, and heed the words of Cornell biologist James G. Needham (1888–1957), who once wrote: It is a monstrous abuse of the science of biology to teach it only in the laboratory—Life belongs in the fields, in the ponds, on the mountains, and by the seashore. So, armed with this book, consider that your next assignment. —Don Rittner Schenectady, New York ENTRIES A–Z A ABO blood groups Blood group antibodies (A, B, This hormone also acts as a stress agent that helps a plant deal with adverse conditions. For example, ABA accumulates on leaves and causes stomata to close, reducing the loss of water when a plant begins to wilt. In 1963, abscisic acid was first identified and characterized by Frederick Addicott and colleagues. In 1965, the chemical structure of ABA was defined, and in 1967, it was formally called abscisic acid. AB, O) that may destroy red blood cells bearing the antigen to which they are directed; also called “agglutinins.” These red-cell antigens are the phenotypic expression of inherited genes, and the frequency of the four main groups varies in populations throughout the world. The antigens of the ABO system are an integral part of the red-cell membrane as well as all cells throughout the body and are the most important in transfusion practice. See also LANDSTEINER, KARL. absorption spectrum Different pigments absorb light of different wavelengths. For example, chlorophyll effectively absorbs blue and red. The absorption spectrum of a pigment is produced by examining, through the pigment and an instrument called a spectroscope, a continuous spectrum of radiation. The energies removed from the continuous spectrum by the absorbing pigment show up as black lines or bands and can be graphed. abortion The termination of gestation before the fetus can survive on its own. abscisic acid (ABA) A plant hormone (C15H20O4) and weak acid that generally acts to inhibit growth, induces dormancy, and helps the plant tolerate stressful conditions by closing stomata. Abscisic acid was named based on a belief that the hormone caused the abscission (shedding) of leaves from deciduous trees during the fall. At times when a plant needs to slow down growth and assume a resting (dormant) stage, abscisic acid is produced in the terminal bud, which slows down growth and directs the leaf primordia to develop scales that protect the dormant bud during winter. Because the hormone also inhibits cell division in the vascular cambium, both primary and secondary growth are put on hold during winter. abyssal zone The portion of the ocean floor below 1,000–2,000 m (3,281–6,561 ft.), where light does not penetrate and where temperatures are cold and pressures are intense. It lies seaward of the continental slope and covers approximately 75 percent of the ocean floor. The temperature does not rise above 4°C. Because oxygen is present, a diverse community of invertebrates and fishes do exist, and some have adapted to harsh environments such as hydrothermal vents 1 2 acclimatization of volcanic creation. Food-producing organisms at this depth are chemoautotrophic prokaryotes and not photosynthetic producers. See also OCEANIC ZONE. shared the 1953 Nobel Prize in physiology or medicine with HANS KREBS. See also KREBS CYCLE. achiral See CHIRALITY. acclimatization Acclimatization is the progressive physiological adjustment or adaptation by an organism to a change in an environmental factor, such as temperature, or in conditions that would reduce the amount of oxygen to its cells. This adjustment can take place immediately or over a period of days or weeks. For example, the human body produces more erythrocytes (red blood cells) in response to low partial pressures of oxygen at high altitudes; short-term responses include shivering or sweating in warmblooded animals. accommodation The automatic reflex adjustment that allows the focal length of the lens of an eye to change to focus on an object. The lens shape, more convex for near objects and less convex for distant objects, is caused by ciliary muscles acting on the elastic property of the lens. acid A chemical capable of donating a HYDRON (proton, H+) or capable of forming a covalent bond with an electron pair. An acid increases the hydrogen ion concentration in a solution, and it can react with certain metals, such as zinc, to form hydrogen gas. A strong acid is a relatively good conductor of electricity. Examples of strong acids are hydrochloric (muriatic), nitric, sulfuric, while examples of mild acids are sulfurous and acetic (vinegar). The strength of an acidic solution is usually measured in terms of its pH (a logarithmic function of the H+ ion concentration). Strong acid solutions have low pHs (typically around 0–3), while weak acid solutions have pHs in the range 3–6. See also BASE; PH SCALE. acidity constant The equilibrium constant for splitting off a HYDRON from a BRØNSTED ACID. acetylcholine (ACh) One of the most common neurotransmitters of the vertebrate nervous system, ACh is a chemical (CH3COOCH2CH2N+(CH3)3) that transmits impulses between the ends of two adjacent nerves or neuromuscular junctions. Released by nerve stimulation (exciting or inhibiting), it is confined largely to the parasympathetic nervous system, where it diffuses across the gap of the synapse and stimulates the adjacent nerve or muscle fiber. It rapidly becomes inactive by the enzyme cholinesterase, allowing further impulses to occur. acetyl CoA A compound formed in the mitochondria when the thiol group (–SH) of coenzyme A combines with an acetyl group (CH3CO–). It is important in the Krebs cycle in cellular respiration and plays a role in the synthesis and oxidation of fatty acids. Fritz Albert Lipmann (1899–1986), a biochemist, is responsible for discovering coenzyme A and cofactor A, or CoA (A stands for acetylation), in 1947. He acid-labile sulfide Refers to sulfide LIGANDs, the BRIDGING LIGANDs in IRON–SULFUR which are released as H2S at acid pH. See also FERREDOXIN. e.g., PROTEINS, acid precipitation Because pure precipitation (e.g., rain) is slightly acidic (due to the reaction between water droplets and carbon dioxide, creating carbonic acid) with a potential pH of 5.6, acid precipitation refers to precipitation with a pH less than 5.6. Acid precipitation includes rain, fog, snow, and dry deposition. Anthropogenic (man-made) pollutants (carbon dioxide, carbon monoxide, ozone, nitrogen and sulfur oxides, and hydrocarbons) react with water vapor to produce acid precipitation. These pollutants come primarily from burning coal and other fossil fuels. Sulfur dioxide, which reacts readily with water vapor and droplets (i.e., has a short residence time in the atmosphere as a gas), has been linked to the weathering actin 3 (eating away) of marble structures and the acidification of freshwater lakes (consequently killing fish). Natural interactions within the biosphere can also lead to acid precipitation. acoelomate A solid-bodied animal lacking a body cavity, the space between the gut (digestive tract) and body wall. Simple animals do not have a body cavity as higher animals do; this body cavity is called a coelom in mammals and contains the gut (a cavity by itself), heart, and lungs, for example. Acoelomates are bilateral animals and are triploblastic (have three layers: ectoderm, endoderm, and mesoderm). They can move forward and have a degree of cephalization (centralization of neural and sensory organs in the head). Representative phyla of acoelomates are the Platyhelminthes: flatworms that include the Turbellaria (nonconfined flatworms such as planarians), Monogenea (monogeneans), Trematoda (trematodes, or flukes), and Cestoidea (tapeworms). There are more than 20,000 species of flatworms living in wet environments such as marine or freshwater bodies and damp terrestrial areas. See also COELOM. aconitase A name for citrate (isocitrate) hydro-LYASE (aconitate hydratase), which catalyzes the interconversion of citrate, cis-aconitate ((Z)-prop-1-ene-1,2,3-tricarboxylate), and isocitrate. The active ENZYME contains a catalytic [4FE-4S] CLUSTER. Mariposa lily from California. An example of an actinomorphic, radially symmetrical flower. (Courtesy of Tim McCabe) contact with the egg help the sperm head penetrate the egg for fertilization. Directly behind the acrosome is the haploid nucleus (single set of unpaired chromosomes) that contains the genetic material. See also FERTILIZATION. actin A globular protein found in muscle tissue as acrosome The acrosome is a special area or compartment that is located at the tip of the head of a sperm cell. It contains special digestive enzymes that on acrosome The acrosome is a special area or compartment that is located at the tip of the head of a sperm cell. thin filaments and in microfilaments that form portions of cell cytoskeletons. Actin links into chains, and paired chains twist helically around each other, forming microfilaments in muscle and other contractile elements in cells. Actin and myosin filaments interact to initiate muscle contraction. Tropomyosin and troponin are two protein molecules associated with actin filaments in muscle. Tropomyosin runs along the length of the actin filament and covers the area of the actin molecule that interacts with myosin when at rest. On the other hand, when a muscle is contracted, tropomyosin is replaced with troponin as it binds to calcium ions. Troponin is