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All important information about virus and bacteria
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Noakhali Science & Technology University Department Of Education,Year-2,Term-1 Subject-Botany-1 Course code-EDN-2108 Direct in response on 2nd incourse Topic-Making a presentation over botany subject for higher secondary class as a teacher Submitted by Name-Morsheda Nur Tisha Department Of Education Roll-BKH1919033F Submitted to Name: S.M. Mushfiquer Rahman Ashique Lecturer Department Of Education
Microbiology • Microbiology, study of microorganisms, or microbes, a diverse group of generally minute, simple life-forms that include bacteria, archaea, algae, fungi, protozoa, and viruses.
What are the Characteristics of Organisms? • All living things are composed of cells • All living things perform certain chemical processes such as growth and digestion • All living things can reproduce • All living things either make their own nutrients or ingest nutrients from the environment • All living things respond to stimuli such as light and touch
Virus A virus is a non-cellular particle made up of genetic material and protein that can invade living cells and reproduce. – Causes infections in ALL life forms
What are viruses • Infectious agents, NOT CELLS • No nucleus, organelles, cytoplasm • Can replicate ONLY inside a living cell – Obligate Intracellular Parasites • Contain only 1 type of genetic molecule, either DNA OR RNA • Do not grow • NOT ALIVE • Some viruses have:– Envelop – lipid rich layer outside protein coat • Envelop may have proteins that help infect cells • Ex. HIV, Flu • Can use presence or absence of envelop to classify – Tails – Spikes – Legs
Living characteristics • Every virus is made of either DNA or RNA and protein. • They can reproduce inside the living cells. • Like pathogenic bacteria, it also cannot live without living cells. • Genetic recombination is found to occur in this. • Mutation is found to occur. • They have genetic objects. • They can grow and can increase within host cells • There are specific races or strains • They can be transmitted from one host to another. • They are capable of multiplication in the host. • They exhibit mutations • They show irritability because they react to heat, radiation, and chemicals. • They are capable to reproduce and hence can increase their number. • They are resistant to antibiotics.
Nonliving Characteristics • It has no distinct cell. • An individualist virus cannot make am organic activities without living on another living cell. • They have no cytoplasm, nucleus and another cell organizes and metabolic enzymes. • Crystal granules can be made. • They don’t contain both RNA and DNA together. • They lack metabolic activity outside the living cells. • They lack ribosomes and cellular enzymes necessary for nucleic acid and protein synthesis. • They have a lack of cell membrane and cell wall. • Don’t undergo their own metabolism and no motility • No energy conversions and no reactions to stimuli • No reproduction outside living cells • They can be crystallized and can be precipitated • The outside of the cells act like inert chemicals • They don’t show growth, development, nutrition, reproduction, etc. • Can’t grow in size, shape or something like that. Don’t possess any sort of nutrients.
SIMPLE (GENERAL) STRUCTURE • The general structure of most viruses is a simple protein, outer coat, called a capsid which encloses nucleic acid (either DNA or RNA). There are genes located on the nucleic acid but there numbers are small compared to complex organisms.
Replication of Virus • Viruses are obligate parasites. They can only function by using the energy of their hosts. In order to replicate themselves they must use the structures and energy of the host they have occupied. • The chart below shows the replication of a bacteriophage. This virus infects bacteria. It takes about 30 minutes to complete its replication cycle. STAGES OF VIRUS REPLICATION A virus will replicate many times when it invades a host cell. There are 4 stages involved in this process: 1. Attachment: The virus attaches to a host cell. In the case of the bacteriophage it will attach to a bacterium. 2. Entry: The virus forms a hole in the membrane or cell wall of the host. The nucleic acid of the virus enters the host cell. 3. Synthesis: The virus’ nucleic acid is used to make new viral nucleic acid and proteins for the new viruses being produced. (The host cells’ DNA becomes deactivated.( 4. Assembly: New viruses are made inside the host cell. 5. Release: The host cell bursts to release the new viruses. The bursting is called lysis.
QS:Is virus smaller than bacteria? • Viruses are tinier than bacteria. • To see bacteria we use light microscopy (400x magnification?). Viruses can only be viewed using an electron microscope. • Virus is 10–100 times smaller than bacteria. • Virus can stay inside the bacteria. • In fact the largest virus is smaller than the smallest bacteria.
QS:Economical & Biological importance of VirusUseful roles: • In preparing antidotes/vaccine: Pox, mumps, polio, jaundice etc diseases can be controlled by penetrating using or dead virus in the human body as vaccines. • In controlling harmful animals and insects: Some animals and insects which are harmful to humans can be controlled by some special virus. • In the laboratory: Virus is used in the lab, as the simplest living model. In the research of genetics, the virus is used mostly. It is an important subject in genetic engineering. • In the evidence of evolution: Virus plays a vital role to acquire knowledge about the trend of evolution and the process of formation of living organisms because the virus contains both living and non-Living characteristics. • In nanotechnology, viruses can be considered as organic nanoparticles. Because of their size, shape, and structures have been used as a template for organizing materials on the nanoscale.
Harmful roles: • Different diseases like common Cold, Influenza, Mumps, Pox, Polio, Yellow fever, Harpish, Aids etc. are caused by the attack of the virus. • Human viruses, especially those that caused to deaths, can have larger negative economic effects. For example, Africa’s Ebola virus occurred in economic losses of over $1.6 billion. • The virus destroys plenty of bacteria which useful for humans. • Viruses can cause a destructive influence on human societies. They can be weaponized for biological warfare. *QS:What is retrovirus?-A retrovirus is a type of virus that inserts a copy of its RNA genome[a] into the DNA of a host cell that it invades, thus changing the genome of that cell.
Bacteria What are Prokaryotes? • Most microbes are prokaryotes • Exist almost every where on earth • Cells that do not have a nucleus • Contains a rigid cell wall, cytoplasm and ribosomes. • Identifying Prokaryotes: Cell Shape Cell Wall Movement What is Bacteria? Bacteria are unicellular prokaryotic microorganisms. They are prokaryotes: they have no nucleus and no organelles with membranes.
QS:Importance of Bacteria For environment: 1.Natural scavengers: 2. Nutrition: They are an important source of vegetative nutrition in the marine environment. For plants:As a source of manure (fertilizer enhancers). For humas & animals:Bacteria like Entero-coli live in the gut intestines of animals in a symbiotic fashion. They are friendly bacteria helping in degradation of unused food and help in its expulsion from the body.Some bacteria like E.coli which are present in the body resist the growth of harmful bacteria like typhoid. For medical:1.For antibiotic production 2. For the production of vaccines. 3. For genetic engineering
Negative impacts: • Bacteria like the Salmonella can cause diarrhea in humans. 90% of the gastrointestinal infections we suffer are caused by ingestion of food infested with the negative kind of bacteria. Escherichia coli, proteus or Klebsiella in extreme doses are harmful and can also spoil food . Diseases caused by Bacteria: Tooth decay,Lyme disease,Tetanus,Tuberculosis,Pneumonia,Cholera
