 Importance of the virology, how much important are the viruses in our daily life? Just like you can see the polio virus, maybe everybody know about the polio virus, how much in the children we use the vaccination and it is the dead virus actually for the vaccine we use for the polio virus. Similarly, everybody know about the name of the viruses and how much important is this in our daily life. We are causing the disease and until now we still don't have the curement for this disease which is caused from the viruses so we will study a little bit about the what we need to study about the viruses first of all the viruses are totally different from the other microorganisms which have evolved until now or which have been discovered until now they are unique properties they are living non-living characteristics in the same animal it means that they are just made up of just we have studied before from the DNA and protein they don't have large materials which are the bacteria they are little bit big as compared to viruses the viruses are made up of non-living and non-living characteristics most importantly we are unable to cultivate sometimes in the laboratory the some of the viruses just like hepatitis virus it's really very difficult and we just need about the primates to cultivate the viruses we cannot cultivate in the experimental animals in the mice in the rabbits or somewhere else so it is really very difficult to cultivate the viruses to study them for different diseases they have the simplest structure of the microorganisms discovered until now just only two things just I said before DNA or RNA and protein we will study structure next the protein quote how from which material it has been made up of and the DNA so the simplest structure they have until now complex interaction with the host they need the host to replicate replication just like this replication within the host they need the host to replicate and their interaction with the host is really very complex and there is need to study such a interaction to study an important class of pathogens so we will just see about the different pathogens which have been discovered until now and we need first of all the biggest one we will see that the parasites parasites the biggest microorganisms which have been discovered until now its example is the helmet we have the three different kinds of but we have a lot of kinds of the parasites but most importantly three of them the round worms the flat worms and the ascaras and the other things so the tape worms are the one of the examples are helmets which are called the round worms the parasites are biggest microorganisms discovered until now then is the protozoa protozoa is also the type of the parasites and it is causing the disease which is we can for example the most famous disease is malaria or the it is also caused by the protozoa these are the present in the in the blood of the host and they cause the disease then we have the fungi its example is tinnia are at least fit at least foot it is a very famous disease and it is caused by the fungi and then the microorganisms which are very famous and which are causing the diseases in all over the world are the bacteria bacteria are actually prokaryotes and they are causing a lot of diseases just like the tuberculosis just like the leprosy or and many other diseases are caused by the bacteria and we have also the antibiotic which is the medicine which can kill the or which can deactivate the bacteria which is called antibiotic however we don't have any any antiviral or and we have antiviral to deactivate but we actually don't have to cause the disease and viruses viruses are very important and the diseases very famous are the you can see the polio in which we have discussed before then we have the disease HIV the AIDS which we are still the human beings are unable to control the disease because it is causing the side effects or it is causing the towards our immune system so we are unable to control the HIV disease however lot of then the prion the presently discovered particles are the prion so from here you can see the different microorganisms which are causing the disease we can divide them into two parts cellular part cellular which are the living organisms and causing the disease then the non-living a cellular which are non-living organisms and which are causing the disease then the study of the pathogenesis of the viruses that how much the viruses are causing the disease and how much the effect of the disease in the viruses there is the life cycle of the viruses is very important that from where the virus has been originated and how it is causing the disease which are the different aspects which are going to cause the disease from which steps it is going and causing the disease and then the structure of the viruses as we studied that it is a simplest structure however different viruses have the different structures just like you can see the polio virus it's the deactivate or live virus vaccine we use then the adeno viruses herpes viruses and the vaccine viruses if we know the structure of the viruses it's very easy to cause some of the some of the how they are working and how they are using so it is easy to have the some pure procurement or curement of the those viruses now it's very important that how we can cultivate the viruses in the laboratory for the different purposes we need to cultivate the different microorganisms just like bacteria just like the parasites similar is the case with the viruses so there are three tissue culture the embryo-nated eggs and live animals are used to cultivate the viruses in the laboratory tissue culture method and embryo-nated eggs methods are the same methods which we use the other microorganisms similarly the bacteria we can also use sometimes in the live animal however from the virus point of view it is very important that there are some viruses which we are not able to cultivate in the embryo-nated eggs or tissue culture material or some other way so we have to need the live animals to cultivate these viruses