By virtue of their reproductive cycle, all viruses must possess a mechanism for all of the below except exiting the cell. gaining entry into the host cell. using host cell enzymes to translate viral proteins. incorporating their genetic material into the host genome.

All viruses possess a mechanism except exiting the cell

Explanation:

There are two main types of reproductive cycle in viruses, the lytic cycle and the lysogenic cycle.

In the lytic cycle, the bacteriophage attaches itself to the host cell through its tail fibers and gain contact with the host cell wall. The tip of the tail make a hole in the bacterial cell wall by means of enzyme lysozyme. Through this hole or point of entry, the viral genome enters the host cell and transcribe some mRNAs to form enzymes over the host ribosomes and degrades the host DNA and mRNAs. It takes over of the entire cellular machinery. Different components combine to form new phages particles or viruses The eclipse period is the period between entry of viral nucleoid into the host cell and the bursting of host cell to release new viruses.

Contrastingly, in lysogenic cycle, the phage DNA does not take over the control of cellular machinery of the host instead produces a repressor and undergoes reduction to temperate or non violent state.

transcription is a process in which information is rewritten. it is something our cells must do, in a more specialized and narrowly defined way. in biology, transcription is the process of copying out the dna sequence of a gene in the similar alphabet of rna. it needs to happen in the nucleus because that's where the dna is. dna is always inside the nucleus unless the cell is dividing.

transcription is the first step in gene expression, which involves copying a gene's dna sequence to make an rna molecule. transcription is performed by rna polymerases. it has three stages: initiation, elongation, and termination. rna molecules must be processed after transcription in eukaryotes.

explanation:

long version:

the protein synthesis consists two processes which are, transcription and translation. transcription takes place in the nucleus. it uses dna as a template to make an rna molecule. rna then leaves the nucleus and goes to a ribosome in the cytoplasm, where translation occurs. transcription is the first part of the central dogma of molecular biology: dna → rna. it is the transfer of genetic instructions in dna to messenger rna (mrna). during transcription, a strand of mrna is made that is complementary to a strand of dna.  

these three stages are:

  initiation: in which   is the beginning of transcription.occuring when the enzyme rna polymerase binds to a region of a gene called the promoter. this signals the dna to unwind so the enzyme can ‘‘read’’ the bases in one of the dna strands. the enzyme is now ready to make a strand of mrna with a complementary sequence of bases.

    elongation: in which is the addition of nucleotides to the mrna strand. rna polymerase reads the unwound dna strand and builds the mrna molecule, using complementary base pairs. there is a brief time during this process when the newly formed rna is bound to the unwound dna. during this process, an adenine (a) in the dna binds to an uracil (u) in the rna.

    termination: in which is the ending of transcription, and occurs when rna polymerase crosses a stop (termination) sequence in the gene. the mrna strand is complete, and it detaches from dna.

answer:

sequence 1- deletion

                  2- duplication

                  3- insertion

                  4- substitute

                  5- inversion