There are various types of viruses in the world, As a representative of viruses, T2 Phage is introduced here with its importance.
Structure: T2 Phage is a cellular. Its body is divided into two parts- head and tail; the head is hexagonal and the tail is rod-shaped, a protein shell surrounds the body. Inside the shell, there is a’ double-strand DNA in its head. At the upper end of the tail there is a collar, and at the lower end, there is a base plate, some spikes and attachment fibres. In Viruses, there is no nucleus, cell membrane, cytoplasm and other organelles.
Multiplication: Viruses can multiply only inside some other living cells. T2 Phage attacks a Bacterium. It keeps the protein shell outside; its DNA enters into the Bacterial Cell. Later on it (the Viral DNA) makes the Bacterial DNA inactive and make many new Viruses. Ultimately the Bacterial cell is destroyed and new Viruses came out.
Importance: (I) T2 Phage kills Bacteria, (2) Widely used m Genetic Engineering.
Importance of Viruses: Deadly human diseases like Measles, Pox, Polio, Hydrophobia, Influenza, Harpies, Viral hepatitis etc. are caused by Viruses. Viruses cause about 300 diseases of various plants and crops. Many diseases of domestic animals like -Cow, Goat, Pig, etc. are caused by Viruses. Vrtises are also responsible for fatal diseases like – AIDS (Acquired Immune Deficiency Syndrome), Cancer etc. Vaccines of several diseases like -Pox, Polio, and Hydrophobia etc. are also produced from Viruses.