The cell membrane is also highly selective barrier enabling the cell to concentrate a specific metabolite and excrete waste material. Apr 30, 2020 bacterial morphology and structure pptpowerpoint presentation, biology notes edurev is made by best teachers of. The term refers to the general aspects of biological form and arrangement of the parts of a plant or an animal. These three have in common not only their meaning, but also the fact that each contains an alveolar fricative phoneme, either s or z. This results in dental plaque and many bacteria can stick to tooth surfaces and cause decay once s. After what seemed like an hour, the doctor would look at me for two minutes, swab the back of my. The three forms are in complementary distribution, because each occurs where the others cannot, and it is. 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. But most cells are surrounded in addition by a thick cell wall the grampositives and another. Some bacteria can cause diseases for human, animals and plants.
It can be found in soil, air, water, and living bodies. The bacterial protoplasm is limited externally by a thin, elastic cytoplasmic membrane which is 510nm thick and consists mainly of. Bacteria bacteria classification by morphology, biochemistry, and other features. Viruses of all shapes and sizes consist of a nucleic acid core, an outer protein coating or capsid, and sometimes an outer envelope. 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. Virions, single virus particles, are 20250 nanometers in diameter. Indeed, bacteria are classified on the basis of many characteristics. Let us learn about morphology and ultrastructure of a bacterial cell. Systematics move deeper into the systematics of bacterial groups by selecting one of the boxes containing a picture classifying bacteria on the basis of their morphology is extremely difficult.
Morphology definition of morphology by merriamwebster. Surface area and volume ratio of bacteria is exceedingly high compared to the same ratio for larger organism of similar shape. The material was dehydrated in alcohol, embedded in prepolymerized methacrylate, and studied in thin sections. 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.
The different response of the two groups to the gram stain is based on fundamental differences in cell wall structure and composition. In some countries this may not be legally possible. Let us make an indepth study of the anatomy of bacterial cell. The below given article will help you to learn about the following things. Cells of listeria monocytogenes, at different stages of growth, were fixed with osmium tetroxide and treated with uranyl acetate. The gram stain, developed in by hans christian gram, characterises bacteria based on the structural characteristics of their cell walls. Morphology and fine structure of fischerella ambigua1 morphology and fine structure of fischerella ambigua1 thurston, e. Share your knowledge share your word file share your pdf file share your ppt file.
Cell division in this organism most closely resembles. Get a printable copy pdf file of the complete article 1. Eukaryote cell difference between prokaryotic and eukaryotic cells. Morphology and ultrastructure of a bacterial cell with. Full text full text is available as a scanned copy of the original print version. Nuclear membrane nucleolus dna single molecule cell division no. The pattern, shape and arrangement are often characteristic of genus. Characteristic gramnegative bacteria grampositive bacteria wall structure they have a thin lipopolysaccharide exterior cell wall. I remember getting sick as a kid and having to sit in the doctors office.
Morphology and structure of bacteria linkedin slideshare. However, a few species are visible to the unaided eyefor example, thiomargarita namibiensis is up to half a millimetre long and epulopiscium fishelsoni reaches 0. These structures are thought to help cells attach to their target environment. Varies with kinds of bacteria, and also related to their age and external environment. Bacterial morphology deals with size, shape, and arrangement of bacterial cells. Based on morphological differences, the ammoniaoxidizing bacteria were separated into four genera. The peptidoglycan layer is thick effect of dye do not retain the crystal violet dye, and react only with a counterstain, generally stain pink. The term anatomy also refers to the study of biological structure but. This simple enclosure can be found only by species living within eukaryotic cells such as mycoplasma spp. Ladyofhats grants anyone the right to use this work for any purpose, without any conditions, unless such conditions are required by law. Relatively large surface area and a small volume of cell substance to be nourished accounts for unusual high rate.
Bacteria grow and spread widely with variety of size and shape. Cells and structures too thin to be seen under ordinary microscope may be. Cover different classification schemes for grouping bacteria, especially the use of the gram stain 2. Many viruses attach to their host cells to facilitate penetration of the cell membrane. The external form and structure of bacteria including shape, size and arrangement of bacteria is a defining charecteristics called morphology. This document is highly rated by students and has been viewed 531 times. This structure is critical barrier separating the inside of cell from environment. 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. Surface layers of bacteria microbiology and molecular biology.
Bacterial classification, structure and function columbia university. 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. On the basis of their reaction to the gram stain, bacteria can be divided into two large groups. Common structures bacteria cell transfer dna under protein conjugation f.
Bacterial cells are about onetenth the size of eukaryotic cells and are typically 0. Bacterial classification, structure and function introduction the purpose of this lecture is to introduce you to terminology used in microbiology. Get a printable copy pdf file of the complete article 7. A procaryotic cellular microorganism, very small size, could be seen with a microscope parameter. Learn quiz microbiology bacterial morphology with free interactive flashcards. Morphology morphology is the study of word formation, of the structure of words. 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.
Definition, morphology, classification and reproduction. In certain species of bacteria, the cells are arranged in pairs, clusters, chains, trichoma and filaments. 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 very small unicellular microorganisms ubiquitous in nature. This work has been released into the public domain by its author, ladyofhats.
Viruses are infectious particles about 100 times smaller than bacteria and can only be observed by electron microscopy. Bacteria are microscopic organisms that are less than 3 micrometeres. In the past, viruses were classified by the type of nucleic acid they contained, dna or rna, and whether they had single or doublestranded nucleic acid. Like carbon dioxide and some other greenhouse gases, it enters the air when people burn oil, gas and. Organization and format errata, author corrections illustrations and tables nomenclature. Vibrio cholerae, the cause of cholera, also produces. The bacterium, despite its simplicity, contains a welldeveloped cell structure which is. Fine structure and replication of bacterial nucleoids. It has its own cellular machinery for growth and metabolism. 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. Links to pubmed are also available for selected references. Because of its minute size, a virus must be studied with the electron microscope.
Outside, and closely covering this, lies the rigid, supporting cell wall. Classification and morphology of bacteria scholar idea. Perhaps the most elemental structural property of bacteria is their morphology. The outer membrane of gramnegative bacteria protects the pg from lytic enzymes. Symposium on the fine structure and replication of bacteria and their parts. Symposium on the fine structure and replication of. Morphology, in biology, the study of the size, shape, and structure of animals, plants, and microorganisms and of the relationships of their constituent parts.
Learn vocabulary, terms, and more with flashcards, games, and other study tools. They have a thin lipopolysaccharide exterior cell wall. Cell membrane is a thin structure that completely surrounds the cell only about 8 nm thick. Morphological characteristics the major morphological characteristics of bacteria include. Discover everything scribd has to offer, including books and audiobooks from major publishers. Streptococcus mutans produces a slime layer in the presence of sucrose. Comparison of the morphology and deoxyribonucleic acid. A recent study of the capsules of streptococcus suis in which several different stabilizing techniques were used. Bacteria classification by morphology, biochemistry, and. The most important and widely used differential stain for bacteria is the gram stain. Choose from 500 different sets of quiz microbiology bacterial morphology flashcards on quizlet. Bacteria display a wide diversity of shapes and sizes, called morphologies.