Pathogen and Immune System and Genetic Engineering?

I have a test on these topics tomorrow and really don't understand anything it would really help to just be told the basics of these
Answer:
Pathogens are the micro organism (germs) that cause disease and often times kill the body. Colds, flu and tuberculosis are examples of diseases of the respiratory system caused by viruses and bacteria. Cholera, dysentery and typhoid are the examples of the digestive ailments. There are other ailments like sore eyes, chicken pox, measles, etc. which are caused by pathogens.

The immune system is the natural defense mechanism of the human body against pathogens. All living organism have immune system to fight or correct abnormalities in the internal system. Vaccines stimulate/activate the immune system to make the body ready for external attacks by pathogens. Scientist believe that proper nutrition, exercise and rest strengthen the immune system.

Genetics is a study that brought us knowledge about genes and chromosomes where the code of our biological characteristics are stored. We call that the genetic code of every cell. Scientists are learning the way to alter this code to our advantage. The study promises to unlock the secrets of beauty, strength and physical immortality.

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In a few paragraphs, you want us to teach you everything you need to know about these topic that take a LIFETIME to master?

Next time, pay more attention in class.

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