Infectious diseases are caused by microorganisms such as viruses, bacteria, fungi or parasites and can spread between individuals. 1  Infectious diseases are caused by microorganisms such as viruses, bacteria, fungi or parasites.2  Microorganisms that cause disease are collectively called pathogens. Many diseases become difficult to control if the infectious agents evolve resistance to commonly used drugs: 2  For example, bacteria can accumulate mutations in their DNA or acquire new genes that allow them to survive contact with antibiotic drugs that would normally kill them.
Southern blot. A Southern blot is a method used in molecular biology for detection of a specific DNA sequence in DNA samples. Southern blotting combines transfer of electrophoresis-separated DNA fragments to a filter membrane and subsequent fragment detection by probe hybridization.
Content analysis is a readily-understood, inexpensive research method. It is unobtrusive, and it doesn't require contact with people. unobtrusive-does not intrude; inconspicuous, out of the way; One can learn much about a media production's policies, target audience, politics, and financial support.Content analysis becomes a more powerful tool when combined with other research methods such as interviews, observation, and use of archival records.It is very useful for analyzing historical material, especially for documenting trends over time. Establishing reliability is easy and straightforward.ontent analysis becomes a more powerful tool when combined with other research methods such as interviews, observation, and use of archival records. It is very useful for analyzing historical material, especially for documenting trends over time.