As the name suggests, silent mutations are point mutations that actually have no visible effect on the protein. This is due to the degeneracy of the genetic code. Several codons actually insert the same amino acid. It is possible to mutate a codon so that it actually inserts the same amino acid. For example, if the codon UCU were mutated to UCG, it will still recruit the amino acid serine.

The other answers describe other types of mutations. Missense mutations are point mutations that result in the swapping of one amino acid for another. Nonsense mutations cause early termination. Frameshift mutations shift the reading frame of the codon sequence, severely altering the protein composition.

Abortive initiation is the process by which RNA polymerase starts short cycles of RNA synthesis. During abortive initiation, RNA polymerase releases short RNA strands before the initiation complex leaves the promoter sequence. Abortive initiation is a common process in both eukaryotes and prokaryotes.

An insertion mutation is a mutation due to an additional nucleotide base pair being added to a DNA sequence. In this case, a cytosine nucleotide has been inserted.

A substitution mutation occurs when a base pair is exchanged for a different base pair. In this case, a thymine nucleotide has been substituted for an adenine nucleotide.

An insertion mutation that occurs where an amount of nucleotides that is not a multiple of three is added to a DNA sequence will shift the reading frame.

A deletion mutation occurs when a base pair is removed from the DNA sequence. In this case, a cytosine nucleotide has been deleted.

Histones are the packaging proteins on which long DNA molecules are coiled before mitosis. In this respect they are involved in cell division, but they are most closely linked to chromosome condensation. During interphase DNA is mostly packaged as euchromatin. Euchromatin is loosely packed and is capable of being transcribed, making it essential for protein synthesis and cell growth during the G1 and G2 phases. During mitosis the DNA condenses into tightly-packed heterochromatin in the form of chromosomes, which allow for cell division. The difference in packaging between euchromatin and heterochromatin comes from histone proteins. During chromosome formation, DNA becomes tightly wound around the histones to create the chromosome structure.

RNA polymerase is the protein that synthesizes an RNA complement to a gene. RNA polymerase binds the template DNA strand and recruits ribonucleotides to build a strand of heteronuclear RNA (htRNA). The htRNA then undergoes modification to become mature mRNA before exiting the nucleus into the cytosol for translation.

DNA polymerase and primase are essential for the replication of DNA. DNA polymerase recruits nucleotides to synthesize the daughter strand of DNA, and primase creates small RNA primers to recruit DNA polymerase to the replication fork. Trypsin is a protease that is not involved in transcription; it helps to digest proteins in the small intestine.

PABP (poly-A-binding protein) binds to the poly-A tail in the 3' UTR of eukaryotic mRNA. It is likely that this species would not have a PABP homolog because it does not have a poly-A tail.

eIF4E binds to the 5' cap. eIF2 is responsible for bringing the first tRNA to the initiation complex. eEF1 is an elongation factor that helps bring tRNAs to the ribosome. 

Proteins are coded for by RNA, which is coded for by DNA. The central dogma of molecular biology is the general sequence for the flow of information in coding for a protein. An mRNA strand is created using the DNA strand as a template. This new strand of mRNA then leaves the nucleus and is used as a template for 3-pronged tRNA molecules carrying amino acids to create a chain, which will eventually create a protein.

The central dogma of molecular biology is the general sequence of DNA to RNA to protein.