Junior+Presentation+2+Group+11

Group 5, Period 6 is A-Cap, Ducky, and Pickles

Explain why antibotics are effective against bacteria but not against viruses. Then outline the principle of challenge and response in terms of memory cells.

Skit the first: Why sometimes effective? Eh? Cast: Bacterium, person, antibody, heavy object Bacterium person wants to rob the person person with a stick, but the antibody person is a NINJA and can beat the bacterium back. (SWORD.) Howsomever, when a heavy object falls on the person person, the antibody NINJA can't do anything about it, because the object doesn't care if you hit it.

Skit one-point-five: Bacteria resistance Cast: Bacterium, person, antibody Bacterium person has learned his lesson! When he comes to mug the person person, he comes with a RIFLE instead. When person person gets his personal NINJA antibody to help, the SWORD is useless, NINJA runs away, and person person gets robbed.

Skit the second: Memory stuff! Woo! What? Cast: B cell (Jedi), antibody (clones), bacteria/antigen (evil robot people) The evil robot people come along and the Jedi is like WHAAAT?? :O So he reacts by making the clones and sends them out to kill the evil robot people. Once the evil robot people are dead, he doesn't need the clones anymore. So he lets them go. But he keeps remembering that in case the robot people come back, he needs to make more clones. The evil robot people do indeed come back; Jedi makes clones; robot people die. THE END.

Ducky: Why antibiotics are effective against bacteria The reason antibiotics work against bacteria is that antibiotics attack substances that are only alive and since the bacteria is alivethe antibiotic attacks it. Another reason that antibiotics attack bacteria is because bacteria have cell walls and antibiotics attack the cell-walls of the bacteria so that the bacteria dies and won’t be able to reproduce. Most of these antibiotics kill bacteria by preventing them from making protein for their cell walls. An antibiotic acts by limiting or stopping (and therefore killing) the growth of a specific microorganism. It probably accomplishes this by interfering with the wall of the bacteria cell at which it is targeted while at the same time having little effect on the body's normal cells. When one is exposed continually to an antibiotic for an illness of long duration (such as rheumatic fever), the targeted bacteria may develop its own defense against the drug. An enzyme that can destroy the drug may be produced by the bacteria, or the cell wall can become resistant to being broken by the action of the antibiotic. When this happens, and it does most frequently in response to long or frequent treatment with penicillin or streptomycin, the patient is said to be "fast" against the drug.

Pickles: Principle of challenge and response with memory cells [] [] Memory cell: A cell in the immune system that, when exposed to a pathogen, replicates itself and remains in the lymph nodes searching for the same antigen, creating a rapid response to any subsequent attack.
 * **B cells** make **10^15** different types of antibodies (but not all at once).
 * A few of each B cell are produced and wait until the body is infected.
 * When this occurs, they multiply to form many clones; this is called **Clonal Selection.**
 * A clone of B cells can **produce large amounts of antibodies quickly** and give immunity to a disease, only after the immune system is challenged by a disease -- this is called the challenge and response system . The immune system needs to "challenged" by a disease, and then the immune system responds by producing a clone of "B" cells which produce large amounts of antibodies to fight and eliminate the pathogen.
 * The creation of memory cells is one of the main goals of vaccination.

A-Cap: Why antibiotics are ineffective against viruses **Explain why antibiotics are effective against bacteria but not viruses.** · [|Antibiotics] are drugs which kill or slow the growth of bacteria. Antibiotics block metabolic pathways of bacteria, inhibiting cell wall formation and protein synthesis, resulting in the death of foreign bacteria. However, viruses are not alive and utilize the organisms host cells to replicate, which are not targeted by antibiotics. In order to kill a virus by antiobiotics human cell has to be killed as well Antibiotics are totally worthless and ineffective for the treatment of flu or other viral diseases. Viruses pose a considerable challenge to the body's immune system because they hide inside cells. This makes it difficult for antibodies to reach them. However, special immune system cells, called T-lymphocytes, can recognise and kill cells containing viruses, since the surface of infected cells is changed when the virus begins to multiply. Many viruses, when released from infected cells, will be effectively knocked out by antibodies, produced in response to infection or previous immunisation.

Antibiotics kill bacteria by interfering with their metabolic processes, but viruses are so simple they use their host cells to perform their activities for them. This is why antibiotics are useless against viral infections. Antiviral drugs work by interfering with the viral enzymes. Antiviral drugs are currently only effective against a few viral diseases, such as influenza, herpes, hepatitis B and C and HIV, but research is ongoing. A naturally occurring protein, called interferon (which the body produces to help fight viral infections), can now be produced in the laboratory and is used to treat hepatitis C infections. Viral diseases should //never// be treated with antibiotics. Sometimes a person with a viral disease will develop a bacterial disease as a complication of the initial viral disease. For example, children with chickenpox often scratch the skin sores caused by the viral infection. Bacteria such as staph can enter those lesions and cause a bacterial infection. The doctor may then prescribe an antibiotic to destroy the bacteria. The antibiotic, however, will not work on the chickenpox virus. It will work only against staph. Antibiotics do not affect viruses, but many flu deaths are due to secondary bacterial infections such as pneumonia. Antibiotics would be used to treat these cases.