Protecting the cell against physical damage and invading pathogens. The LPS layer surrounds the peptidoglycan layer and acts as an endotoxin (poison) in pathogenic bacteria (disease causing bacteria). Along with plants, prokaryotic organisms also contain cell walls. It is made up of matrix and microfibrils. In bacteria cell wall contains polymer of amino acid and sugar known as . He has a master's degree in Physics and is currently pursuing his doctorate degree. The cell wall consists of a central lamella, a primary cell wall, and sometimes a secondary cell wall. In the absence of a sturdy cell wall, plants would wilt and the internal organelles would be unable to function. By LadyofHats (Own work) [Public domain]. It acts like a skeletal framework of the plants. One of these very important characteristics is the cell wall. It is composed of cellulose in the form of microfibrils. Darvill JE, McNeil M, Darvill AG, Albersheim P. Structure of Plant Cell Walls: XI. The cell wall is responsible for providing support, protection, and shape to the cell. The plant cell wall supports and protects internal structures and organelles. Cell wall controls and regulates the direction of cell growth. Plant Cell Structures & Shape | What Does the Vacuole Do? Secondary walls are composed mainly of cellulose and __________, a hard, aromatic polymer. Links to PubMed are also available for Selected References. Discover the function of the cell wall in a plant cell and find out what plant cell walls are made of. In addition to protecting the plant from mechanical, viral, and insect damage, the secondary cell wall also facilitates cell-to-cell communication via plasmodesmata that form in the middle lamella. Plant cell wall is a semi permeable layer. government site. Plant cell wall structure. ThoughtCo, Sep. 7, 2021, thoughtco.com/cell-wall-373613. It is kind of like the outside bricks of a castle, only, as you will learn as you read on, there are holes throughout this castle. These layers include the primary cell wall, the secondary cell wall, and the middle lamella. The cell wall is located outside the cell membrane. She holds an Education Specialist Degree in Ed. This characteristic of the plant cell wall provides strength to the plant and enables the plant to keep its shape. Learn About Plant Cell Types and Organelles, Endoplasmic Reticulum: Structure and Function, Animal Cells, Tissues, Organs and Organ Systems. Plant Cell Wall- Definition, Structure, Functions, Diagram, Cell Organelles (Plant, Animal)- Structure, Functions, Diagrams, Connective Tissue- definition, structure, cells, types, functions, diseases, Types of Plant Cell- Definition, Structure, Functions, Labeled Diagram, Cell membrane- Definition, Composition, Structure, Functions, Monocot vs Dicot Roots- Definition, Structure, 18 Differences, Examples, Pyramid of energy- Definition, Levels, Importance, Examples, Eubacteria- Definition, Characteristics, Structure, Types, Examples, Natural Selection- Definition, Theory, Types, Examples, Biosphere- Definition, Origin, Components, Importance, Examples, Animal Kingdom- Definition, Characteristics, Phyla, Examples. Plant cell walls are comprised largely of cellulose. It consists of the middle lamella, primary cell wall, plasmodesmata, secondary cell wall, and pits. From the outermost layer of the cell wall, these layers are identified as the middle lamella, primary cell wall, and secondary cell wall. Plasmodesmata represent small channels between cells that transport molecules and ions. Structure of plant cell wall It is a particular matrix that covers the surface of plant cells. Isolation and Characterization of Wall Polysaccharides from Suspension-Cultured Douglas Fir Cells, Complex Carbohydrate Research Center, University of Georgia, Athens, Georgia 30613, Department of Biochemistry, University of Georgia, Athens, Georgia 30613, Richard B. Russell Center of the United States Department of Agriculture, P.O. This process is important when fruit is ripening. A plant cell may consist of either primary wall only or the cell may contain both primary and secondary walls (Fig. She has taught a combination of ESL and STEM courses to secondary and university students. An image of a typical plant cell with the cell wall in green. Eg: Cells of sclerenchyma, tracheids, and vessels. This higher pectin content enables the primary cell wall to be more flexible as it expands and grows. Let us help you know more about it and its existence in various life forms. The cell wall is a protective layer outside the cell membrane that also provides support for the cell's structure. Plant cell wall has minute water filled channels through which water,hormones and gases passes to and fro. Changes in the chemical composition of a cambial cell during its differentiation into xylem and phloem tissue in trees. 305 lessons lessons in math, English, science, history, and more. The cell wall has many important functions in a cell including protection, structure, and support. The cell wall gives the plant its actual shape. The secondary wall also protects the plant from invading bacteria or fungi. "The Structure and Function of a Cell Wall." The main difference between plant and animal cells is that plant cells have a cell wall on the outer layer, whereas animal cells only have a cell membrane. Middle School Life Science: Help and Review, Plant Biology & Structure: Help and Review, {{courseNav.course.mDynamicIntFields.lessonCount}}, Complete Flowers: Examples, Definition & Structure, Psychological Research & Experimental Design, All Teacher Certification Test Prep Courses, Joanna Tatomir, Kelly Robson, Christianlly Cena. This power point presentation consists of 64 slides including information about plant and other type of cell wall. Genes encoding enzymes capable of synthesizing or . 1. All plant cells contain the cell wall like bacteria, fungi, archae, and algae. It is found in most plants, bacteria, fungi, and algae. Bacterial cell walls are composed of a sugar and amino acid polymer called peptidoglycan. Primary Wall: The first formed wall of a cell is the primary wall. It is differentiated into the outer layer (S. Each layer is made up of a matrix and microfibrils. Cell Nucleus Overview, Function & Structure | What is a Nucleus? After the cytokinesis, it is the first-formed layer. In the fungi, chitin makes the primary cell wall, and in bacteria murein makes it. As the plant cell matures, the secondary cell wall is deposited inside the primary cell wall. Protection is provided by the cell wall against the physical shocks and mechanical strengths. Careers, XIX. Cell Junction Functions & Types | What are Tight Intercellular Junctions, Viruses Lesson for Kids: Definition & Facts, Bacterial Plasmids | Function, Types & Uses. Lysosome Function & Structure | What are Lysosomes? The cell walls of various species also take on a variety of forms. With all of this strength, you would think nothing could squish a dandelion. Moreover, the plant cells would burst due to the turgor pressure present within each cell. See cell wall diagrams and identify different parts of a plant cell structure. It contains various components and has a defined structure. Bailey, Regina. Microfibrils are embedded in the gel-like matrix. An official website of the United States government. What is the Importance of Bacterial Cell Walls? 1984;53:625-63. doi: 10.1146/annurev.bi.53.070184.003205. Try refreshing the page, or contact customer support. It is also very flexible. As a result of lacking cell walls, animal cells tend to be of odd sizes and shapes. The layers of the cell have a different composition; however, all of them contain similar components. Christianlly has taught college Physics, Natural science, Earth science, and facilitated laboratory courses. The carbohydrate components make up approximately 90% of the primary wall, and are critical to wall function. Cell walls primary function is mechanical support. Dr. Jeremy Burgess/Science Photo Library/Getty Images. They form a protoplasmic continuum called symplast. A cell wall is a specialized structure that surrounds every cell of a plant, just __________ the cell membrane. The noncellulosic polysaccharides accounted for 26% of the cell walls, cellulose for 23%, protein for 34%, and ash for 5%, for a total of 88% of the cell wall. In between adjacent cells is the middle lamella, a pectin-filled region that helps plant cells to remain attached to one another. There are passageways for nutrients to enter and waste to leave. A redwood tree and a dandelion both have cell walls on the outside of all of their cells. These are holes that allow for nutrients to enter the cell as well as waste to exit the cell. Along with this, other substances like proteins and lignin can also be found in this layer. Any plant cell which is devoid of the cell wall is called the protoplast. and transmitted securely. https://www.thoughtco.com/cell-wall-373613 (accessed November 8, 2022). Alongside, the shape of cell walls is different for different organisms. Matrix is made up of water, hemicelluloses, pectin, lipids, and proteins. Animal cell: Lysosomes (organelles that digest macromolecules), and centrioles (cylinders of microtubules in the centrosome, involved in cellular division). The chemical composition of the matrix is almost similar to the matrix of the primary cell. It forms after the growth and development of the cell. It helps stop the plant from getting squished. More pectin is found in the primary cell wall when compared to the other layers of the cell wall. Eg: gas, salt, sugar, hormones. Primary cell wall forms the only cell wall in the immature meristematic and. Those holes do make the cell vulnerable, but they are important to the function of the cell. Microfibrils of the secondary cell wall is made up of cellulose and lignin. about navigating our updated article layout. flashcard set{{course.flashcardSetCoun > 1 ? Get unlimited access to over 84,000 lessons. Containing enzymes, pectin is highly resistant to compression and contributes to the overall strength of the plant cell. The cell wall of fungi is made of chitin. A cell wall is a structural layer surrounding some types of cells, just outside the cell membrane. It consists of three layers, namely, primary, secondary and the middle lamella. The cell wall of bacteria is made of the protein, lipid, and polysaccharides complex. The cell wall protects the plant and cells from the many insects and pathogens that could harm the plant, but the cell wall still has its vulnerable areas. Prevention of water loss happens because of the presence of a cell wall. It represents the outer layer that is shared by its neighbors. The cell walls are there to give the plants their shape and support; however, the cell walls act and are constructed a little different to meet the needs of the particular plant. The gram-negative bacterial cell wall also contains an outer layer of lipopolysaccharides (LPS). These are absent in eukaryotic organisms. Its like a teacher waved a magic wand and did the work for me. Cell wall was first seen in cork cells by Hooke in 1665. PLANT CELL WALL STRUCTURE 20. The LPS layer also protects gram-negative bacteria against certain antibiotics, such as penicillins. All rights reserved. Plus, get practice tests, quizzes, and personalized coaching to help you This is present adjacently with the cell membrane. Every plant cell has a cell wall layer which is a major distinguishing factor between a plant cell and an animal cell. Joanna holds a PhD in Biology from the University of Michigan and is currently working towards a degree in Veterinary Medicine at Michigan State University. What is the Function of the Plant Cell Wall? Cell walls are comprised of cellulose, a form of complex carbohydrate which makes up the structural components of plants and some types of algae. FOIA From these, a network is formed with the structural proteins leading to cell wall formation. The microfibrils are layered on top of one another to create a network into which other compounds are embedded, including pectin, lignin, and soluble protein. Principles of Biology (First edition). Structure of the Plant Cell Wall Plant cell walls are three-layered structures with a middle lamella, primary cell wall and secondary cell wall. The main components of fungal cell walls are chitin, glucans, and proteins. This micrograph image shows a plant cell and its internal organelles. Plant cell wall structure and function - This lecture explains about to the structure and function of plant cell wall. Once the plant cell finishes growing, the secondary cell wall is formed inside the primary cell wall. Peptidoglycan is a polymer composed of double-sugars and amino acids (protein subunits). The top layer is the strangely-named middle lamella. The primary function of the cell wall is to protect and provide structural support to the cell. It also filters the molecules passing in and out of it. Dicot glucuronoxylan consists of a linear backbone of (1,4)-linked xylose residues substituted with (1,2)-linked . Retrieved from https://www.thoughtco.com/cell-wall-373613. A major role of the cell wall is to form a framework for the cell to prevent over expansion. It is present in between the two adjacent cells. They transfer cytoplasmic materials among adjacent cells. Cellulose fibers group together to form bundles called microfibrils. However, all cells are not similar. In the tertiary cell wall, xylan is also present in it. The plant cell wall consists of three layers. Bethesda, MD 20894, Web Policies Hundreds of genes are involved in building such a natural masterpiece. It performs several important functions, the list of which is as follows: The cell wall of the plants provides rigidity, structure, and strength to the cell. Cell Biology, Genetics, Molecular Biology, Evolution & Ecology (First edition). The xylan resembled that extracted by NaOH from dicot cell walls in that it contained 2,4- but not 3,4-linked xylosyl residues. I feel like its a lifeline. S. H. CLARKE 1 Nature . The cell wall of these organisms is made of peptidoglycan. Xylan, glucomannan and alpha-cellulose fractions. These substances can be released from the host plants cell wall i.e DAMPs (Damage-associated Molecular patterns) or they can be from the pathogen cell wall i.e PAMPs( Pathogen-associated Molecular patterns). Courses on Khan Academy are always 100% free. Primary wall is about 0.1 m thick normally, but the walls of collenchyma may be 10 m thick. The cell wall is one of the most integral components of a cell wall. It is also called the plasma membrane. The cell wall is formed by the protoplast. Each layer has its own unique structure and function. The plasma membrane or cell membrane is a double-layered structure that surround the cell. The composition of the cell wall varies based on the organism. It is also called the plasma membrane. Because cell walls are found in many prokaryotic organisms, scientists believe that both plants and fungi have retained this ancestral trait from their prokaryotic ancestors. 91 988-660-2456 (Mon-Sun: 9am - 11pm IST), Want to read offline? This is formed of amino acids and sugar. The cell wall of root hairs helps in the absorption of sap from the soil. Cell wall is tough and has high tensile strength. Home Cell Biology Plant Cell Wall- Definition, Structure, Functions, Diagram. Treatment of LiCl-extracted Douglas fir walls with an endo--1,4-polygalacturonase released only small, additional amounts of pectic polysaccharide, which had a glycosyl-linkage composition similar to that of rhamnogalacturonan I. Xyloglucan oligosaccharides were released from the endo--1,4-polygalacturonase-treated walls by treatment with an endo--1,4-glucanase. A Survey of the Walls of Suspension-cultured Monocots. Cutin and cutin waxes are present in some epidermal cells of the leaf and stem. It is present in the inner side of the middle lamella. Animal cells do not have a cell wall. It is the outer rigid protective supportive and semi transparent covering of plant cells, fungi and some protists. Algal cell wall are made up of agar and carrageenan such as polysaccharide, which are present in plants. The plant cell wall is an elaborate extracellular matrix that encloses each cell in a plant. It is present in between the two adjacent cells. The morphology, chemistry, and staining properties of the tertiary cell wall are different from the primary and secondary cell walls. While all plant cells have a middle lamella and primary cell wall, not all have a secondary cell wall. It provides a boundary between the cell and its environment. It is the presence of the water-filled channels which allows the free diffusion of water and water-soluble substances. Finally, additional xyloglucan and small amounts of xylan were extracted from the endo--1,4-glucanase-treated walls by 0.5 n NaOH. (2016). Other non-cellulosic polysaccharides include xyloglucan, glucan, xylan, mannan, and callose. Cell Wall Structure Plant Cell Walls The main component of the plant cell wall is cellulose, a carbohydrate that forms long fibers and gives the cell wall its rigidity. English PD, Maglothin A, Keegstra K, Albersheim P. A Cell Wall-degrading Endopolygalacturonase Secreted by Colletotrichum lindemuthianum. It is formed before the growth and development of the cell. The partial purification and characterization of cell wall polysaccharides isolated from suspension-cultured Douglas fir (Pseudotsuga menziesii) cells are described. This layer provides permeability, and its also the thickest layer. The synthesis of cell wall in controlled by Golgi bodies. will also be available for a limited time. Additional functions of the cell wall include: Dr. David Furness, Keele University/Science Photo Library/Getty Images. Providing the strength, structural support and maintaining the shape of the cell. After the cell grows completely, this wall is formed in the inner part of the primary cell wall. Structure of Plant Cell wall It is derived from the living protoplast. THORNBER JP, NORTHCOTE DH. In addition, the cell wall contains two groups of branched polysaccharides, the pectins and cross-linking glycans. Containing pectin, the middle lamella connects plant cells together. In bacteria, the cell wall serves to keep the cell shape intact and is quite essential for its survival. It is very rigid and is made of cellulose. Cellulose is the major component of cotton fiber and wood, and it is used in paper production. Centrosome Function & Structure | What is a Centrosome? I would definitely recommend Study.com to my colleagues. Chambers RE, Clamp JR. An assessment of methanolysis and other factors used in the analysis of carbohydrate-containing materials. The Structure and Function of a Cell Wall. The formation of the cell wall is guided by microtubules. Other important functions of the cell wall include: The plant cell wall is comprised of three main layers: the primary cell wall, the secondary cell wall, and the middle lamella. Cell Membrane Lesson for Kids: Definition & Function. These walls are composed of 10% arabinan, 2% 3,6-linked arabinogalactan, 23% cellulose, 9% oligo-arabinosides (attached to hydroxyproline), 8% 4-linked galactan, 10% hydroxyproline-rich protein, 16% rhamnogalacturonan, and 21% xyloglucan. Soluble proteins represent a much smaller component of the cell wall. This secondary cell wall is comprised primarily of lignin. sharing sensitive information, make sure youre on a federal It then activates the defense responses of DAMP or PAMP-triggered immunity. Cell wall composition varies depending on the organism. They are also responsible for determining the interaction between polysaccharides and proteins. Burke D, Kaufman P, McNeil M, Albersheim P. The Structure of Plant Cell Walls: VI. Other important carbohydrates include hemicellulose, pectin, and liginin. The secondary cell wall is comprised of cellulose, lignan, and xylan. The cell wall is present in the plant cell and absent in the animal cell which distinguishes them from each other. Apart from Bacteria, Which Organisms Contain a Cell Wall? The outer covering of the cell is called the cell wall. A bundle of cellulose chains called __________ provides additional reinforcement to the primary wall. Plants, like other eukaryotic organisms, possess cells that are enclosed by a membrane. Turgor pressure occurs when the fluid content of a cell pushes the cell membrane against the cell wall. In gram-negative bacteria, the cell wall is not as thick because it contains a much lower percentage of peptidoglycan. The cell walls of Douglas fir were more similar to dicot (sycamore) cell walls than to those of graminaceous monocots, because they had a predominance of xyloglucan over xylan as the principle hemicellulose and because they possessed relatively large amounts of rhamnogalacturonan-like pectic polysaccharides. "The Structure and Function of a Cell Wall." It is the outermost layer of the cell wall. In the secondary cell wall, pits are the unthickened areas or depressed areas. Algal,Fungal,Bacterial and Archaeal cell walls have also been explained. Chand and company Ltd. Houston, K., Tucker, M. R., Chowdhury, J., Shirley, N., & Little, A. It's the combination of this internal pressure, things like the vacuole and, just frankly, the pressure from all of the fluid inside the cell pushing outwards, plus the cell wall kind of holding it all in. The plant cell wall is multi-layered and consists of up to three sections. Cell walls are porous to allow water, carbon dioxi d e, and other substances to pass through. It is made up of calcium and magnesium pectate. Updegraff DM. Cell wall structure varies from species to species. The Plant Cell Wall The plant cell wall is multi-layered and consists of up to three sections. The fibrous structure present in the cell wall maintains the integrity of the structure. These include: Inner Layer: It is made of peptidoglycans, Outer Layer: It is made up of lipopolysaccharides and lipoproteins. The Cell Membranes can be found in both . . These include: 1. Bailey, Regina. The secondary wall has a very similar composition as the primary wall, only it has more stuff in it - it contains lignin, which is very hard and has considerable strength. The Hemicellulose of the Walls of Suspension-cultured Sycamore Cells. This is the thick layer, permeable, and cannot be expanded. The plant cell wall consists of three layers. Know more about our courses. Search for and circle or highlight the words that will complete each of the given clues. Micrometer - Cell measurement, Prokaryotic - Cell with no organelles (ex: bacteria), Eukaryotic - Cell with organelles (ex: plant and animal), Protein - Most important substance a cell makes, Cytoplasm - Jelly like substance inside of a cell, Lipid - Another name for fat, Plasmodesmata help in the transfer of cytoplasmic materials among adjacent cells. The cell wall is made up of two layers, a middle lamella, and a primary cell wall and sometimes a secondary cell wall. This cell wall is formed of cellulose which allows the wall the stretch and grows easily. Alongside, cell walls also protect the internal components of the cell. The cell wall is like a barrier between the external environment and the internal components of the cell. Bauer WD, Talmadge KW, Keegstra K, Albersheim P. The Structure of Plant Cell Walls: II. You can find out more about our use, change your default settings, and withdraw your consent at any time with effect for the future by visiting Cookies Settings, which can also be found in the footer of the site. The primary cell wall of the plant is made of cellulose. They also contain enzymes that help to breakdown the cell wall, allowing the plant to change its structure. The plant cell wall is unique to plants and plays many vital roles to making plants what they are. The dandelion's cell wall provides support and limited __________ to bend as the wind blows. Moreover, the cell wall helps plants to maintain turgor pressure. document.getElementById( "ak_js_1" ).setAttribute( "value", ( new Date() ).getTime() ); 2022 The Biology Notes. The plant cell wall is multi-layered and consists of up to three sections. Now the cell wall is made out of a material called cellulose or chitin or peptidioglycan. Structure of plant cell wall It is a specialized matrix that covers the surface of the plant cell. . These structures are known as organelles. __________ is an acidic substance extracted from the cell walls of plants, which can resist compression. Plant Cell Structure and Function Even though cells differ in size and complexity, they contain many of the same substances and they carry out similar life functions. The cell wall appears as the thin layer between the cells and the nucleus is the prominent, round organelle with the smaller red nucleolus. The Tertiary Cell Wall 19. Plant cell walls are primarily made of cellulose, which is the most abundant macromolecule on Earth. In some plant cells, there is the presence of another cell wall beneath the secondary cell wall. In plant's cell wall it consist of cellulose, hemicellulose, pectin along with other polymers such as lignin, cutin and suberin. That's why a plant is able to grow, and be upright. Much like the skeleton of an animal, the cell wall helps to provide structure to a plant, by using turgor, or hydrostatic pressure, to maintain the size and shape of the plant. During the infection, oligosaccharides elicitors can be released. Extraction of isolated cell walls with 1.0 m LiCl solubilized pectic polysaccharides with glycosyl-linkage compositions similar to those of rhamnogalacturonans I and II, pectic polysaccharides isolated from walls of suspension-cultured sycamore cells. This pectin-lignin matrix enables cellulose to provide the mechanical strength needed by plant tissues to sustain turgor pressure and facilitate photosynthesis. Membrane Proteins | Functions, Types & Structure. are also deposited in the secondary cell wall. Ultra structure of plant cell wall has also been high lighted. These stacked layers increase the thickness of the cell wall. Cytoplasm Function & Role | What is Cytoplasm? 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The secondary cell wall is situated inner to the primary cell wall. When the cell is kept in the hypotonic solution, it prevents the osmotic bursting of the cell. Plasmodesmata Function & Formation | What is Plasmodesmata? The main functions of the cell wall are to provide structure, support, and protection for the cell. Talmadge KW, Keegstra K, Bauer WD, Albersheim P. The Structure of Plant Cell Walls: I. The cell wall comprises elements like carbohydrates, cellulose, pectin, hemicellulose, and other minerals in smaller amounts. Inside the cell wall are chloroplasts (dark green), the site of photosynthesis, and the nucleus (orange), which contains the cell's genetic information. A New Pectic Polysaccharide. plant cell All cell walls contain two layers, the middle lamella and the primary cell wall, and many cells produce an additional layer, called the secondary wall. Cellulose is found not only in plants but also is synthesized by certain bacterial species. A plant cell wall is constructed around the outside of the cell to give plants a strong and protective outer layer. Get a printable copy (PDF file) of the complete article (2.5M), or click on a page image below to browse page by page. It provides mechanical support as the skeletal framework in the plant. Structure and function of the primary cell walls of plants Annu Rev Biochem. A diagram showing the three layers of the plant cell wall. All living things are composed of cells. The cell wall prevents and controls the expansion of the cell. Cellulose is a structural carbohydrate and is considered a complex sugar because it is used in both protection and structure. plant cell wall. Give the Definition of a Cell Wall and Its Functions. Pectin is a branched polysaccharide which forms a gel-like substance that helps to 'glue' adjacent plant cells together.