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What are Pathogens and how they invade host ?


 What are Pathogens?

Pathogens are the organisms which cause disease in living things.

For example., Bacteria, viruses, Fungi, protozoa, helminth, parasites etc. 

How parasites cause harm to host ?

Parasites causes harm to the host by living in (or on ) them and multiply in large numbers.

For example, Malaria, a disease caused by parasite.

How pathogen invade host ?

Pathogens enter the body by various places of the body like skin ,mouth, etc and multiply , interfere with normal necessary activities.

It results in morphological & functional damage.

How Pathogens survive in the body of host ?

Pathogens have to adapt to life within the environment of the host.

For example., The pathogens that enter the gut must know a way of surviving in the stomach at low pH (1.5 to 3.5) which is acidic in nature.

And survive in the presence of digestive enzymes.


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