Viruses can enter into the cell of the host either without or with the viral capsid. The nucleic acid of the bacteriophages enter the host cell as naked beings thus leaving behind the capsid out of the cell. Animal and plant viruses can enter through the endocytosis. Some of the enveloped viruses enter the cell when the viral envelope unites directly with the cell membrane. Upon entry into the cell, the degradation of the viral capsid occurs after which the viral nucleic acid is liberated thus becoming available for the processes of transcription and replication.