Presentation on theme: "Viruses and Bacteria By Brad Washburn. What are Viruses? Viruses are too small to be seen by the naked eye. They can't multiply on their own, so they."— Presentation transcript:
Viruses and Bacteria By Brad Washburn
What are Viruses? Viruses are too small to be seen by the naked eye. They can't multiply on their own, so they have to invade a 'host' cell and take over its machinery in order to be able to make more virus particles.
What are Viruses? (continued) Viruses consist of genetic materials (DNA or RNA) surrounded by a protective coat of protein. They are capable of latching onto cells and getting inside them. The cells of the mucous membranes, such as those lining the respiratory passages that we breathe through, are particularly open to virus attacks because they are not covered by protective skin.
What are Bacteria? Bacteria are organisms made up of just one cell. They are capable of multiplying by themselves, as they have the power to divide. Their shapes vary, and doctors use these characteristics to separate them into groups. Bacteria exist everywhere, inside and on our bodies. Most of them are completely harmless and some of them are very useful. But some bacteria can cause diseases, either because they end up in the wrong place in the body, or simply because they are 'designed' to invade us.
How are Viruses and Bacteria Spread? A person with a cold can spread the infection by coughing and/or sneezing.cold Bacteria or viruses can be passed on by touching or shaking hands with another person. Touching food with dirty hands will also allow viruses or bacteria from the intestine to spread.
How are Viruses and Bacteria are Spread. (continued) Body fluids such as blood and saliva can contain the infecting organisms and transmission of such fluids, for example by injection or sexual contact, is important, particularly for viral infections like hepatitis or AIDS.
Shapes of Bacteria There are thousands of species of bacteria but they all come in 3 different shapes. Bacilli are rod-shaped. Cocci are spherical. Spirilla are spiral-shaped.
The Virus The virus is a type of parasite that is neither alive or dead. Inside the head, you see a yellow strip. This is the DNA or RNA of the virus. Below it is the tail that is connected to the end-plate. This is where the legs are connected. How Viruses Reproduce
How A Virus Reproduces To reproduce, the virus must inject its RNA into the host cell and then mutate that cells DNA to match its own. The virus usually dies after this encounter but the cell bursts with other viruses which then go and attack other host cells.
How a Bacteria Reproduces Most bacteria reproduce using a process called "binary fission." To do this, a single bacterium will grow to twice its normal size and then split into two "daughter" cells. The two new cells are exact copies of the original bacterium. Bacteria can also reproduce sexually.
Types of Viruses Ebola Smallpox Measles Mumps Rabies Common Cold Chicken Pox Hepatitis HIV Influenza Polio Hanta Virus
Types of Bacteria (cocci) Tuberculosis E. Coli Tetanus Diphtheria
Types of Bacteria (spirilla) Syphilis
Bacteria Facts One healthy bacterium, given the proper environment, could reproduce into a colony of more than 2 million in just seven hours. There are more bacterium on your body than there are humans on the entire planet. An area of skin as small as 6.5 square cm (1 square inch) may be home to more than half a million bacterium.
Bacteria Facts (continued) Bacteria help our bodies with digestion and produce needed vitamins. Bacteria also help us by destroying harmful organisms within our bodies. Bacteria are used to make cheese, milk, sourdough bread and yogurt. 99% of all bacteria are helpful.
Virus Facts Viruses are neither classified as dead or alive. RNA in Viruses are usually unstable and therefore can mutate easily. Antibiotics do not work against viruses. You either fight them, or die.