The Directed Movement of Substances (such As Macromolecules Small Molecules Ions) Into Out of or Within a Cell or Between Cells or Within a Multicellular Organism by Means of Some Agent Such As a Transporter or Pore.
A Multi Organism Process in Which a Virus Is a Participant. the Other Participant Is the Host. Includes Infection of a Host Cell Replication of the Viral Genome and Assembly of Progeny Virus Particles. in Some Cases the Viral Genetic Material May Integrate Into the Host Genome and Only Subsequently Under Particular Circumstances 'complete' Its Life Cycle.
A Membrane Bounded Organelle of Eukaryotic Cells in Which Chromosomes Are Housed and Replicated. in Most Cells the Nucleus Contains All of the Cell's Chromosomes Except the Organellar Chromosomes and Is the Site of RNA Synthesis and Processing. in Some Species or in Specialized Cell Types RNA Metabolism or DNA Replication May Be Absent.