Jan 11, 2018 morphological characteristics the major morphological characteristics of bacteria include. They are soft protoplasmic bodies, spherical or disklike. Bacterial morphology deals with size, shape, and arrangement of bacterial cells. Morphology morphology is the study of word formation, of the structure of words. Outside, and closely covering this, lies the rigid, supporting cell wall.
Ladyofhats grants anyone the right to use this work for any purpose, without any conditions, unless such conditions are required by law. The term anatomy also refers to the study of biological structure but. The three forms are in complementary distribution, because each occurs where the others cannot, and it is. Nuclear membrane nucleolus dna single molecule cell division no. Apr 30, 2020 bacterial morphology and structure pptpowerpoint presentation, biology notes edurev is made by best teachers of. Relatively large surface area and a small volume of cell substance to be nourished accounts for unusual high rate. The study of bacteria is known as bacteriology and it is a branch of microbiology. Some bacteria can cause diseases for human, animals and plants. Discover everything scribd has to offer, including books and audiobooks from major publishers. This results in dental plaque and many bacteria can stick to tooth surfaces and cause decay once s. Module morphology and classification of bacteria microbiology 4 notes 1. The morphology and fine structure by patrick echlin botany department, university of cambridge a study has been made of the morphology and fine structure of young and old cells of the apoplastidic alga glaucocystis nostochinearum itzigsohn which contains endophytic bluegreen algae. Bacteria are known to evolve specific traits to survive in their ideal environment.
Morphology of flagella size 520m long, width17nm parts filament made of flagellin semirigid, forms a left handed helix and exits the cell hook acts as a sleeve from which the filament emerges transmits rotatory motion from basal body to filament basal body consists of m,s,p,l rings connected by a rod shaped structure in gram positive bacteria only 2 rings. It has its own cellular machinery for growth and metabolism. Bacteria under the microscope morphology, discussion, types. The pattern, shape and arrangement are often characteristic of genus. It can be found in soil, air, water, and living bodies. Bacterial cell morphology, staining reactions, classification of bacteria the protoplast is bounded peripherally has a very thin, elastic and semipermeable cytoplasmic membrane a conventional phospholipid bilayer.
Terms in this set 14 gross morphology of bacterial cell. In this essay, we discuss the diversity of bacterial morphology and its implications for understanding both the mechanistic and the adaptive basis of morphogenesis. Cells and structures too thin to be seen under ordinary microscope may be. Microscopic morphology and staining of individual bacteria. Start studying bacterial morphology and cell structure 5. These three have in common not only their meaning, but also the fact that each contains an alveolar fricative phoneme, either s or z. Streptococcus mutans produces a slime layer in the presence of sucrose. Abstract the purpose of this exercise is to gain experience in bacterial morphologies in prepared wetmounted slides and interpreting the findings of bacteria through direct and indirect staining technique. Typically, morphology is contrasted with physiology, which deals with studies of the functions of organisms and their parts. These are abnormal forms derived from bacteria of abnormal morphology cocci, bacilli, vibrio due to variation in the laboratory.
Bacteria and archaea are classified by direct examination with the light microscope according to their morphology and arrangement the basic morphologies are spheres coccus and roundended cylinders bacillus. Perhaps the most elemental structural property of bacteria is their morphology. A recent study of the capsules of streptococcus suis in which several different stabilizing techniques were used. Lecture 710 the morphology fine structure of bacteria free download as pdf file. Bacteria are microscopic organisms that are less than 3 micrometeres.
Bacteria have been grouped into prokaryotic, which means absence of. Spiral bacteria are another major bacterial cell morphology. This structure is critical barrier separating the inside of cell from environment. Bacteria classification by morphology, biochemistry, and. While they are very small, they are diverse and vary in shape and size. The last five are secondary in that they represent a suite of morphologically associated mechanisms that bacteria use to deal with the primary forces. Indeed, bacteria are classified on the basis of many characteristics. The morphology and fine structure of bacteria flashcards. Most cells have the capacity to store only one kind of material producing a characteristic inclusion which can be stained and microscopically observed. After what seemed like an hour, the doctor would look at me for two minutes, swab the back of my. In some countries this may not be legally possible. The type of peptidoglycan is thus a reliable but only very broad biochemicalmorphological characterization of species in the domain bacteria. However, colony morphology is not a reliable way to identify bacteria, as many different types of bacteria have similar colony morphology.
Although genetic divergence highlights the evolutionary relationships of bacteria, morphological and biochemical features of bacteria remain important in the identification and classification of those organisms. But there may be others such as helically twisted cylinders spirochetes, cylinders curved in one plane selenomonads and unusual morphologies such as the square, flat boxshaped. The gram stain, developed in by hans christian gram, characterises bacteria based on the structural characteristics of their cell walls. Learn quiz microbiology bacterial morphology with free interactive flashcards. Surface area and volume ratio of bacteria is exceedingly high compared to the same ratio for larger organism of similar shape. Classification and morphology of bacteria scholar idea. A number of bacteria characteristically store deposits of nutrient materials, usually phosphate, sulphur, carbohydrate or fat in structure called cytoplasmic inclusions or granules. The bacterium, despite its simplicity, contains a welldeveloped cell structure which is. This work has been released into the public domain by its author, ladyofhats. Morphology, ultrastructure, and molecular phylogeny of the. Microbiology module morphology and classification of bacteria microbiology 2 notes zmost bacteria possess peptidoglycan, a unique polymer that makes its synthesis a good target for antibiotics zprotein synthesis takes place in the cytosol with structurally different ribosomes fig. Gross morphology and fine structures free download as powerpoint presentation.
This document is highly rated by students and has been viewed 531 times. Bacteria are very small unicellular microorganisms ubiquitous in nature. Oct 26, 2017 classification and morphology of bacteria scholar idea. It allows a large proportion of clinically important bacteria to be classified as either gram positive or negative based on their morphology and differential staining. Vibrio cholerae, the cause of cholera, also produces. However, some bacteria are variable in shape and have a single characteristic form. Bacterial structure characteristic gramnegative bacteria grampositive bacteria wall structure they have a thin lipopolysaccharide exterior cell wall. Here are your useful notes on the morphology of bacteria. Morphology, in biology, the study of the size, shape, and structure of animals, plants, and microorganisms and of the relationships of their constituent parts. We consider how best to leverage genomic data and recent experimental developments in order to advance our understanding of bacterial shape and its functional importance. The different response of the two groups to the gram stain is based on fundamental differences in cell wall structure and composition.
The term colony morphology refers to the visible characteristics of a colony. Bacteria bacteria classification by morphology, biochemistry, and other features. The virus is much simpler than the bacterial cell, consisting of a core of nucleic acideither deoxyribonucleic acid dna or ribonucleic acid rnaenclosed in a protective membrane of protein called the capsid. Common structures bacteria cell transfer dna under protein conjugation f. The peptidoglycan layer is thick effect of dye do not retain the crystal violet dye, and react only with a counterstain, generally stain pink. Characteristic gramnegative bacteria grampositive bacteria wall structure they have a thin lipopolysaccharide exterior cell wall. Many bacteria in young cultures, show a mixture of several integrating forms, besides the original structure of the parent type. Until recently the format for this test has been the latex agglutination assay, however a new. Spiral bacteria can be subclassified as spirilla, spirochetes, or vibrios based on the number of twists per cell, cell thickness, cell flexibility, and motility. Morphologists were originally concerned with the bones, muscles, blood vessels, and nerves comprised by the bodies of animals and the roots, stems, leaves, and.
But most cells are surrounded in addition by a thick cell wall the grampositives and another. To name the general structures, and polymers that make up bacterial cell walls. Definition, morphology, classification and reproduction. Stationaryphase and longstationaryphase bacteria were collected after 4 days and 12 days of incubation, respectively. Originally it was detected by leeuwenhoek in 1700 as retractile bodies in the centre of blood corpuscles of salmon blood. Pdf the morphology and fine structure of the ordovician. A procaryotic cellular microorganism, very small size, could be seen with a microscope parameter. Bacteria are single cellular microscopic organisms. These are called pleomorphic corynbacterium, arthrobacter.
The expectation is that by answering this deceptively simple question we may acquire knowledge that will point us to a universal mechanism of shape control. A brief introduction about bacterial antigen, including the morphology and fine structure of bacteria and bacterial virulence factors. To conclude this comparison of fine structure details within order plagiopylida, in trimyema spp. Learn vocabulary, terms, and more with flashcards, games, and other study tools.
They lack rigid cell wall, they are viable, grow and multiply on suitable culture media. A read is counted each time someone views a publication summary such as the title, abstract, and list of authors, clicks on a figure, or views or downloads the fulltext. Choose from 500 different sets of quiz microbiology bacterial morphology flashcards on quizlet. These structures are thought to help cells attach to their target environment. Here, i will discuss only three to give a flavor for how selective pressures impact cell shape. The most prominent feature of a cell when viewed under the microscope is the nucleus. The discussion of bacterial morphology has been dominated by questions about how a cell manages to create a rod shape, which, of course, is but one example of the more general question of how a cell constructs any shape. Share your knowledge share your word file share your pdf file share your ppt file. This means that they are singlecelled organisms without a nucleus membrane nuclear envelope. Morphology and structure of bacteria linkedin slideshare.
Usually these treatments generate nonviable organisms. Bacterial classification, structure and function introduction the purpose of this lecture is to introduce you to terminology used in microbiology. Microscopy has come a long way since leeuwenhoek first observed bacteria using handground lenses. Colonies that differ in appearance are typically different bacterial strains, species, or genera. Varies with kinds of bacteria, and also related to their age and external environment. Bacterial colony morphology and identification of bacteria. I remember getting sick as a kid and having to sit in the doctors office. The bacteria, when treated with antibiotic or they are attacked by the bacteriophages or by cold shock they sometimes, develop unusual, soft, protoplasmic forms of various.
The cell membrane is also highly selective barrier enabling the cell to concentrate a specific metabolite and excrete waste material. Useful notes on the morphology of bacteria discussion. The average volume of a bacterial cell is 1 cubic micron. Fine structure of the deinococcus radiodurans nucleoid. Morphology, structure, chemical composition, functions and significance of nucleus. Morphology and ultrastructure of a bacterial cell with diagram. By combining morphology and gramstaining, most bacteria can be classified as belonging to one of four groups grampositive cocci, grampositive bacilli, gramnegative cocci and gramnegative bacilli.
Bacterial classification, structure and function columbia university. Bacteria were harvested by centrifugation with a sorvall rs28s centrifuge for 5 min at 3,000 rpm. They have a thin lipopolysaccharide exterior cell wall. The term refers to the general aspects of biological form and arrangement of the parts of a plant or an animal. On the basis of their reaction to the gram stain, bacteria can be divided into two large groups. Alternatively, in the grampositive bacteria, the peptidoglycan forms extensively crosslinked multimolecular layers. Morphology and ultrastructure of a bacterial cell with. Bacterial structure and morphology medical microbiology is science of studying microorganisms that are associated with human disease agents of infection include cellular organisms belonging to two of the three recently defined domains of life. Some of the ways these selective forces may affect bacterial morphology are summarized in table 1. The most important and widely used differential stain for bacteria is the gram stain.
Surface layers of bacteria microbiology and molecular biology. The morphology and fine structure of the ordovician cephalodiscus. Let us learn about morphology and ultrastructure of a bacterial cell. Wallless bacteria that can not replicate are referred to as. This simple enclosure can be found only by species living within eukaryotic cells such as mycoplasma spp. Whenever we come upon one of those intensely right words. Eukaryote cell difference between prokaryotic and eukaryotic cells. In certain species of bacteria, the cells are arranged in pairs, clusters, chains, trichoma and filaments. Cell membrane is a thin structure that completely surrounds the cell only about 8 nm thick. The types of microscope are i light or optical microscope ii phase contrast microscope. Aristophanes 450 bce388 bce a powerful agent is the right word. Cover different classification schemes for grouping bacteria, especially the use of the gram stain 2. Bacteria with a thin wall layer and an outer membrane stain red with this. Lecture 710 the morphology fine structure of bacteria gram.