B3 Part 1


Communicable diseases

1) communicable can be spread e.g a cold and non-communicable cannot be spread e.g cancer

2) Direct contact, Air, In Water, In Food, Animals

3) Wash your hands often. Get vaccinated. Use antibiotics sensibly. Stay at home if you have signs and symptoms of an infection. Be smart about food preparation.

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New medicines

1)  Developing a new drug:

  • Researchers target a disease and develop ideal treatment
  • Possible drugs are made in the lab
  • Medicines are tested on cell tissue and cultures to see if they're toxic
  • Medicines are tested on animals to see how they may affect humans
  • Clincal trial on humans (healthy then affected patients)
  • The medicine is licensed and can be used by the public but is still monitored

2) Placebo- A dummy drug given to patients during drug trials                                                            Single bind- When only the doctor knows which drug is real and which is placebo                             Double blind- When neither the doctor or patient knows which drug is real or the placebo

3) So that a faulty drug isn't given out to the public which could result in fatalities

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Antibiotics and Vaccinations

1) Antibiotics are chemicals that kill bacteria only. They are produced by other living organisms and were discovered by Sir Alexander Flemming

2)  They protect people from diseases however they could go wrong and you could be injected with that disease and be ill

3)Vaccines are a dead or inactive form of the pathogen is injected into the body. A vaccination causes the production of antibodies and the production of memory cells so if the pathogen enters again it will be remembered and the right antibodies will be produced. Herd immunity is when the majority of a group of people are vaccinated against a disease so if a few aren't they will still be protected from the virus

4) Some bacteria has become resistant to antio-biotics. This is caused by a mutation in their genes

5)Anti-biotics do not kill viruses as viruses reroduce inside human cells so it's hard to destroy viruses without damaging human cells

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Pathogens and Diseases

1) a) The mean division time for bacteria population A is 20 minutes. If the observation begins with one bacterium, calculate how many bacteria will be present after six hours.                                       b) place the plate on a non-reflective surface. Take a ruler or caliper that measures in millimeters and place the "0" in the center of the antibiotic disk. Measure from the center of the disk to the edge of area with zero growth

2) An organism that causes a disease. Bacteria reproduce by binary fission. In this process the bacterium, which is a single cell, divides into two identical daughter cells. Binary fission begins when the DNA of the bacterium divides into two.

3) They produce anti-toxins, they make anti-bodies, they ingesr the bacteria. 

4) Nose hairs and mucus, Acid in the stomach, The skin as a barrier, Mucus in the trachea and bronchi

5) They reproduce rapidly and destroy cells (virus) or produce poisons (bacteria)

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