Protects the Cells of Plants • Chloroplast
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Cell Wall Chemistry Roger M
3 Cell Wall Chemistry Roger M. Rowell1,3, Roger Pettersen1, James S. Han1, Jeffrey S. Rowell2, and Mandla A. Tshabalala 1USDA, Forest Service, Forest Products Laboratory, Madison, WI 2Department of Forest Ecology and Management, University of Wisconsin, Madison, WI 3Department of Biological Systems Engineering, University of Wisconsin, Madison, WI CONTENTS 3.1 Carbohydrate Polymers ..........................................................................................................37 3.1.1 Holocellulose ..............................................................................................................37 3.1.2 Cellulose .....................................................................................................................37 3.1.3 Hemicelluloses............................................................................................................39 3.1.3.1 Hardwood Hemicelluloses ..........................................................................41 3.1.3.2 Softwood Hemicelluloses............................................................................42 3.1.4 Other Minor Polysaccharides .....................................................................................43 3.2 Lignin......................................................................................................................................43 3.3 Extractives ..............................................................................................................................45 3.4 Bark.........................................................................................................................................46 -
The Origin of Alternation of Generations in Land Plants
Theoriginof alternation of generations inlandplants: afocuson matrotrophy andhexose transport Linda K.E.Graham and LeeW .Wilcox Department of Botany,University of Wisconsin, 430Lincoln Drive, Madison,WI 53706, USA (lkgraham@facsta¡.wisc .edu ) Alifehistory involving alternation of two developmentally associated, multicellular generations (sporophyteand gametophyte) is anautapomorphy of embryophytes (bryophytes + vascularplants) . Microfossil dataindicate that Mid ^Late Ordovicianland plants possessed such alifecycle, and that the originof alternationof generationspreceded this date.Molecular phylogenetic data unambiguously relate charophyceangreen algae to the ancestryof monophyletic embryophytes, and identify bryophytes as early-divergentland plants. Comparison of reproduction in charophyceans and bryophytes suggests that the followingstages occurredduring evolutionary origin of embryophytic alternation of generations: (i) originof oogamy;(ii) retention ofeggsand zygotes on the parentalthallus; (iii) originof matrotrophy (regulatedtransfer ofnutritional and morphogenetic solutes fromparental cells tothe nextgeneration); (iv)origin of a multicellularsporophyte generation ;and(v) origin of non-£ agellate, walled spores. Oogamy,egg/zygoteretention andmatrotrophy characterize at least some moderncharophyceans, and arepostulated to represent pre-adaptativefeatures inherited byembryophytes from ancestral charophyceans.Matrotrophy is hypothesizedto have preceded originof the multicellularsporophytes of plants,and to represent acritical innovation.Molecular -
Cell Wall Ribosomes Nucleus Chloroplast Cytoplasm
Cell Wall Ribosomes Nucleus Nickname: Protector Nickname: Protein Maker Nickname: Brain The cell wall is the outer covering of a Plant cell. It is Ribosomes read the recipe from the The nucleus is the largest organelle in a cell. The a strong and stiff and made of DNA and use this recipe to make nucleus directs all activity in the cell. It also controls cellulose. It supports and protects the plant cell by proteins. The nucleus tells the the growth and reproduction of the cell. holding it upright. It ribosomes which proteins to make. In humans, the nucleus contains 46 chromosomes allows water, oxygen and carbon dioxide to pass in out They are found in both plant and which are the instructions for all the activities in your of plant cell. animal cells. In a cell they can be found cell and body. floating around in the cytoplasm or attached to the endoplasmic reticulum. Chloroplast Cytoplasm Endoplasmic Reticulum Nickname: Oven Nickname: Gel Nickname: Highway Chloroplasts are oval structures that that contain a green Cytoplasm is the gel like fluid inside a The endoplasmic reticulum (ER) is the transportation pigment called chlorophyll. This allows plants to make cell. The organelles are floating around in center for the cell. The ER is like the conveyor belt, you their own food through the process of photosynthesis. this fluid. would see at a supermarket, except instead of moving your groceries it moves proteins from one part of the cell Chloroplasts are necessary for photosynthesis, the food to another. The Endoplasmic Reticulum looks like a making process, to occur. -
The Structure, Function, and Biosynthesis of Plant Cell Wall Pectic Polysaccharides
Carbohydrate Research 344 (2009) 1879–1900 Contents lists available at ScienceDirect Carbohydrate Research journal homepage: www.elsevier.com/locate/carres The structure, function, and biosynthesis of plant cell wall pectic polysaccharides Kerry Hosmer Caffall a, Debra Mohnen a,b,* a University of Georgia, Department of Biochemistry and Molecular Biology and Complex Carbohydrate Research Center, 315 Riverbend Road Athens, GA 30602, United States b DOE BioEnergy Science Center (BESC), 315 Riverbend Road Athens, GA 30602, United States article info abstract Article history: Plant cell walls consist of carbohydrate, protein, and aromatic compounds and are essential to the proper Received 18 November 2008 growth and development of plants. The carbohydrate components make up 90% of the primary wall, Received in revised form 4 May 2009 and are critical to wall function. There is a diversity of polysaccharides that make up the wall and that Accepted 6 May 2009 are classified as one of three types: cellulose, hemicellulose, or pectin. The pectins, which are most abun- Available online 2 June 2009 dant in the plant primary cell walls and the middle lamellae, are a class of molecules defined by the pres- ence of galacturonic acid. The pectic polysaccharides include the galacturonans (homogalacturonan, Keywords: substituted galacturonans, and RG-II) and rhamnogalacturonan-I. Galacturonans have a backbone that Cell wall polysaccharides consists of -1,4-linked galacturonic acid. The identification of glycosyltransferases involved in pectin Galacturonan a Glycosyltransferases synthesis is essential to the study of cell wall function in plant growth and development and for maxi- Homogalacturonan mizing the value and use of plant polysaccharides in industry and human health. -
IAWA Bulletin N.S., Vol. 3 (1),1982 3 ANTONI V an LEEUWENHOEK
IAWA Bulletin n.s., Vol. 3 (1),1982 3 ANTONI VAN LEEUWENHOEK AND HIS OBSERVATION ON THE STRUCTURE OF THE WOODY CELL WALL by Pieter Baas Rijksherbarium, Leiden, The Netherlands Summary Following general remarks on the life of Van be traced back to negative but ill-informed Leeuwenhoek and his role in wood anatomy, judgements in some authoritative 19th and his account of the structure of a torn vessel 20th century publications (Baas, 1982a, b). wall of nutmeg rootwood is discussed in detail. Van Leeuwenhoek should be credited with The cross-wise orientation of minute 'vessels or many detailed and original wood and bark ana fibres' as observed and interpreted by Van tomical observations, but his work is not easily Leeuwenhoek can be considered to be the first accessible, being scattered in numerous letters, (unintentional) correct record of the fibrillar most of them also dealing with other microsco nature of the woody cell wall. pic subjects. Although most of these letters were published in various instalments and sev Introduction eral languages during Van Leeuwenhoek's life Antoni van Leeuwenhoek was born in 1632, time, this presentation cannot compete with 350 years ago, in Delft (the Netherlands) as the the balanced treatises by Grew and Malpighi, son of a basket maker. Apprenticed to a cloth who each published books solely dealing with merchant, Van Leeuwenhoek's career started as plant structure and function. a shopkeeper. Later he would serve as usher to Interest in Van Leeuwenhoek's plant anato the aldermen, chief warden and wine-gauger of mical work has recently also been revived by the City of Delft, and surveyor to the Court of the rediscovery of some of his sections among Holland. -
Brown Algae and 4) the Oomycetes (Water Molds)
Protista Classification Excavata The kingdom Protista (in the five kingdom system) contains mostly unicellular eukaryotes. This taxonomic grouping is polyphyletic and based only Alveolates on cellular structure and life styles not on any molecular evidence. Using molecular biology and detailed comparison of cell structure, scientists are now beginning to see evolutionary SAR Stramenopila history in the protists. The ongoing changes in the protest phylogeny are rapidly changing with each new piece of evidence. The following classification suggests 4 “supergroups” within the Rhizaria original Protista kingdom and the taxonomy is still being worked out. This lab is looking at one current hypothesis shown on the right. Some of the organisms are grouped together because Archaeplastida of very strong support and others are controversial. It is important to focus on the characteristics of each clade which explains why they are grouped together. This lab will only look at the groups that Amoebozoans were once included in the Protista kingdom and the other groups (higher plants, fungi, and animals) will be Unikonta examined in future labs. Opisthokonts Protista Classification Excavata Starting with the four “Supergroups”, we will divide the rest into different levels called clades. A Clade is defined as a group of Alveolates biological taxa (as species) that includes all descendants of one common ancestor. Too simplify this process, we have included a cladogram we will be using throughout the SAR Stramenopila course. We will divide or expand parts of the cladogram to emphasize evolutionary relationships. For the protists, we will divide Rhizaria the supergroups into smaller clades assigning them artificial numbers (clade1, clade2, clade3) to establish a grouping at a specific level. -
Primary and Secondary Plant Cell Walls: a Comparative Overview*
36 New Zealand Journal of Forestry Science 36(1) PRIMARY AND SECONDARY PLANT CELL WALLS: A COMPARATIVE OVERVIEW* PHILIP J. HARRIS School of Biological Sciences, The University of Auckland Private Bag 92019, Auckland, New Zealand [email protected] (Received for publication 23 November 2005; revision 3 February 2006) ABSTRACT Light and transmission electron microscopy are used in studying wall morphology and histochemical methods, including immunocytochemistry, can be used to locate specific compounds in walls. All plant cell walls contain a fibrillar phase of cellulose microfibrils and a matrix phase which contains a high proportion of non-cellulosic polysaccharides that vary in their chemical structures, depending on wall type and plant taxon. The non-cellulosic polysaccharide compositions of three common wall types — lignified secondary walls, non-lignified secondary walls, and non-lignified primary walls — exemplify this. The principles used in constructing the most recent models of non-lignified primary walls can be used in modelling lignified secondary walls. Keywords: primary cell walls; secondary cell walls; cell-wall models; non- cellulosic polysaccharides; transmission electron microscopy; light microscopy; chemistry; lignified walls; immuno- cytochemistry; histochemistry INTRODUCTION This review provides a brief comparative overview of primary and secondary cell walls of seed plants. A primary wall is defined as a wall that is deposited while the cell is still enlarging, whereas a secondary wall is deposited on the primary wall after cell expansion has stopped, and can be seen in sections as a structurally distinct layer (or layers) that is often very much thicker than the primary wall (Harris 2005a). At maturity, the different cell types can be grouped according to whether they have only a primary wall or both a primary and a secondary wall. -
(SSC) Region of Chloroplast Genomes1
NEWS & VIEWS AMERICAN JOURNAL OF BOTANY LETTER TO THE EDITOR Sources of inversion variation in the small single copy (SSC) region of chloroplast genomes1 Joseph F. Walker 2 , Robert K. Jansen 3,4 , Michael J. Zanis 5 , and Nancy C. Emery6,7 Modern sequencing technology has led to a proliferation of whole- Walker et al., 2014 ; Zhang et al., 2014 ; Wang et al., 2015 ). Th ese genome sequences of chloroplasts in a growing number of plant analyses compare the SSC orientation among lineages using a single lineages, bringing opportunities for comparisons that provide in- plastome to represent each lineage and thus have missed the within- sights into the evolutionary history of the plastomes and their host individual variation that exists in this region. Currently, whole- plants ( Jansen et al., 2007 ; Doorduin et al., 2011 ). Amid the emerg- chloroplast genomes are published in GenBank without preference ing literature in this area is a hypothesis that the small single copy for the orientation of the SSC region, leading to apparent variation (SSC) region is a “hotspot” for inversion events (sensu Liu et al., in the orientation of the SSC region among individuals that is actu- 2013 ) because diff erent orientations of the region have been re- ally due to chloroplast heteroplasmy within individuals ( Wolfe and ported in relatively high frequencies among closely related taxa Randle, 2004 ), as originally described by Palmer (1983) . For exam- ( Liu et al., 2013 ; Walker et al., 2014 ). We would like to draw atten- ple, two sequences of Lactuca sativa that have been independently tion to a study by Palmer (1983) that bears heavily on this discus- published (NC_007578 and DQ_383816) were entered with diff er- sion, yet has been overlooked by several authors of publications ent orientations of the SSC region, which could be interpreted as investigating whole-chloroplast genome sequence order, including a major inversion existing within the species if the investigators are one study by some of the authors of this letter ( Walker et al., 2014 ). -
Cell Structure and Function in the Bacteria and Archaea
4 Chapter Preview and Key Concepts 4.1 1.1 DiversityThe Beginnings among theof Microbiology Bacteria and Archaea 1.1. •The BacteriaThe are discovery classified of microorganismsinto several Cell Structure wasmajor dependent phyla. on observations made with 2. theThe microscope Archaea are currently classified into two 2. •major phyla.The emergence of experimental 4.2 Cellscience Shapes provided and Arrangements a means to test long held and Function beliefs and resolve controversies 3. Many bacterial cells have a rod, spherical, or 3. MicroInquiryspiral shape and1: Experimentation are organized into and a specific Scientificellular c arrangement. Inquiry in the Bacteria 4.31.2 AnMicroorganisms Overview to Bacterialand Disease and Transmission Archaeal 4.Cell • StructureEarly epidemiology studies suggested how diseases could be spread and 4. Bacterial and archaeal cells are organized at be controlled the cellular and molecular levels. 5. • Resistance to a disease can come and Archaea 4.4 External Cell Structures from exposure to and recovery from a mild 5.form Pili allowof (or cells a very to attach similar) to surfacesdisease or other cells. 1.3 The Classical Golden Age of Microbiology 6. Flagella provide motility. Our planet has always been in the “Age of Bacteria,” ever since the first 6. (1854-1914) 7. A glycocalyx protects against desiccation, fossils—bacteria of course—were entombed in rocks more than 3 billion 7. • The germ theory was based on the attaches cells to surfaces, and helps observations that different microorganisms years ago. On any possible, reasonable criterion, bacteria are—and always pathogens evade the immune system. have been—the dominant forms of life on Earth. -
The Structure and Function of Plastids
The Structure and Function of Plastids Edited by Robert R. Wise University of Wisconsin, Oshkosh WI, USA and J. Kenneth Hoober Arizona State University, Tempe AZ, USA Contents From the Series Editor v Contents xi Preface xix A Dedication to Pioneers of Research on Chloroplast Structure xxi Color Plates xxxiii Section I Plastid Origin and Development 1 The Diversity of Plastid Form and Function 3–25 Robert R. Wise Summary 3 I. Introduction 4 II. The Plastid Family 5 III. Chloroplasts and their Specializations 13 IV. Concluding Remarks 20 Acknowledgements 21 References 21 2 Chloroplast Development: Whence and Whither 27–51 J. Kenneth Hoober Summary 27 I. Introduction 28 II. Brief Review of Plastid Evolution 28 III. Development of the Chloroplast 32 IV. Overview of Photosynthesis 43 References 46 3 Protein Import Into Chloroplasts: Who, When, and How? 53–74 Ute C. Vothknecht and J¨urgen Soll Summary 53 I. Introduction 54 II. On the Road to the Chloroplast 56 III. Protein Translocation via Toc and Tic 58 IV. Variations on Toc and Tic Translocation 63 V. Protein Translocation and Chloroplast Biogenesis 64 VI. The Evolutionary Origin of Toc and Tic 66 VII. Intraplastidal Transport 66 VIII. Protein Translocation into Complex Plastids 69 References 70 xi 4 Origin and Evolution of Plastids: Genomic View on the Unification and Diversity of Plastids 75–102 Naoki Sato Summary 76 I. Introduction: Unification and Diversity 76 II. Endosymbiotic Origin of Plastids: The Major Unifying Principle 78 III. Origin and Evolution of Plastid Diversity 85 IV. Conclusion: Opposing Principles in the Evolution of Plastids 97 Acknowledgements 98 References 98 5 The Mechanism of Plastid Division: The Structure and Origin of The Plastid Division Apparatus 103–121 Shin-ya Miyagishima and Tsuneyoshi Kuroiwa Summary 104 I. -
Algal Chloroplasts Secondary Article
Algal Chloroplasts Secondary article Saul Purton, University College London, London, UK Article Contents . Introduction A great diversity of chloroplasts is found amongst the various algal groups. This diversity . Diversity and Classification of Algae is the result of an intriguing evolutionary process that involved the acquisition of . Origins and Evolution of Algal Chloroplasts chloroplasts by different eukaryotic organisms. Chloroplast Genetics and Molecular Biology . Protein Transport in the Chloroplast . Summary Introduction The chloroplast is one of a family of related biosynthetic and which lack the differentiated structures that organelles (termed plastids) found within the cells of define higher plants (roots, shoots, leaves, etc.). Indeed, plants, eukaryotic algae and certain protists. The primary the algae are often referred to as ‘lower’ or ‘primitive’ role of the chloroplast is the fixation of atmospheric carbon plants. Included within the algae are the prokaryotic through photosynthesis, but it is also the site of synthesis of cyanobacteria (formerly referred to as blue-green algae), many other important compounds including pigments, together with a diverse collection of microscopic and fatty acids, amino acids and nucleotides. Chloroplasts are macroscopic eukaryotes. Algal species can be unicellular, distinguishable from other plastid types in that they filamentous or multicellular and they range in size from the contain chlorophyll and other pigments that are involved unicellular forms that are only a few micrometres in in light energy capture and dissipation. In higher plants, diameter to the giant Laminaria seaweeds that are tens of nonphotosynthetic plastids such as chromoplasts, amylo- metres long. Algae have adapted to life in a wide range of plasts and leucoplasts are found in nongreen tissue and environments. -
Chloroplasts Are the Food Producers of the Cell. the Organelles Are Only Found in Plant Cells and Some Protists Such As Algae
Name: ___________________________ Cell #2 H.W. due September 22nd, 2016 Period: _________ Chloroplasts are the food producers of the cell. The organelles are only found in plant cells and some protists such as algae. Animal cells do not have chloroplasts. Chloroplasts work to convert light energy of the Sun into sugars that can be used by cells. It is like a solar panel that changes sunlight energy into electric energy. The entire process is called photosynthesis and it all depends on the little green chlorophyll molecules in each chloroplast. In the process of photosynthesis, plants create sugars and release oxygen (O2). The oxygen released by the chloroplasts is the same oxygen you breathe every day. Chloroplasts are found in plant cells, but not in animal cells. The purpose of the chloroplast is to make sugars that feed the cell’s machinery. Photosynthesis is the process of a plant taking energy from the Sun and creating sugars. When the energy from the Sun hits a chloroplast and the chlorophyll molecules, light energy is converted into the chemical energy. Plants use water, carbon dioxide, and sunlight to make sugar and oxygen. During photosynthesis radiant energy or solar energy or light energy is transferred into chemical energy in the form of sugar (glucose). You already know that during photosynthesis plants make their own food. The food that the plant makes is in the form of sugar that is used to provide energy for the plant. The extra sugar that the plant does not use is stored as starch for later use. Mitochondria are known as the powerhouses of the cell.