Chapter 9 Flashcards
Give a detailed account of antibiotics
An antibiotic is a type of antimicrobial substance active against bacteria. It is the most important type of antibacterial agent for fighting bacterial infections. They are not useful against viruses.
Antibiotics that inhibit microbial growth are called bacteriostatic, and those that kill bacteria are bactericidal. Those that act against limited varieties are called limitrd spectrum antibodies, like penicillin. Those that act against a wide range are broad spectrum, tetracyclines.
Write a detailed note on antibiotics (part 2) Name major antibiotics.
Sulphonamides: synthetic broad spectrum antibodies. Bacteriostatic, as they inhibit folic acid synthesis in bacteria. Are known to treat urinary track infections and pneumonia.
Tetracylines: broad spectrum antibodies produced by bacteria. Bacteriostatic, inhibit protein synthesis in bacteria. Not used for small children, but treat respiratory and urinary tract infections.
Cephalosporins: broad spectrum, produced by fungi. Bactericidal, as they interfere with cell wall synthesis. Treat pneumonia, sore throats etc.
Write a detailed note on antibiotics (part 3) Why are some illnesses resistant to antibiotics?
When bacteria are exposed to an antibiotic for a long time, they develop an immumity to it. This is accelerated by overuse or misuse.
Resistance may be developed in two ways, general mutation of a transfer of resistance between bacteriums during conjugation. As a result, bacteria are not killed and continue to grow. This makes infections difficult to treat as in the case of TB, the bacteria become drug resistant.
What are Vaccines?
Immunization involves the use of a vaccine, which is the injecting or oral administration of small amounts of antigens that allows the immune system to naturally build a tolerance against that antigen in a safe way so that a complete infection is easily combated.
What is the immune system?
Immunity is the ability of the body to defend itself against infectious agents, foreign cells, and abnormal body cells. An antigen is any foreign substabce tbat triggers and immunity response from the body. B lymohocytes give rise to plasma cells which produce antibodies that neautralize antigens.
What is the mode of action of a vaccine?
At first exposure, tve antigen stimulates the body to produce antibodies, which initially may not be enough. When a vaccination is done a second time, it is called a booster because it stimukates a greater level of antibody production which prevents diseases later on. Memory cells are also produced as a reult, which remain in the blood and provide protection against future infections with the same pathogen.
What is a pathogen?
It is an incredibly broad term in biology that refers to any agent capable of producing a disease.
What is the role of vaccines in producing immunity against specific diseases?
Vaccines increase the number of circukating antibodies to fight against the antigens of disease causing bacteria. Cells each produce antibodies soecialized for a soecific infection, which is why an antibody that fights typhoid may not work on pneumonia causing bacteria. This is why vaccinnes artificially active immunity to fight many diseases. Small pox was permanently eradicated due to vaccines.
What are drugs?
Any substabce that alters normal bodily functions is called a drug. There are two main type of drugs, medicinal and addictive.
Medicinal drugs like antiseptics or aspririn are used in certain medical environments to ensure smooth operations or to aid in a personal aiment like a headache.
Addictive drugs are those drugs that make you dependent on them, like heroin and morphine.
