Describe each process (including differences between bacteria and eukaryotes) and explain the significance of the differences between replication and transcription When first going through DNA replication, the two strands of double helix unwind. Each strand is an outline for the formation of a new, complementary strand. DNA helicase enzymes hang along the DNA molecule, opening the double helix as they move. Once the strands are separated, helix-destabilizing proteins bind to single DNA strands, preventing re-formation of the double helix until the strands are copied. Enzymes called topoisomerases produce breaks in the DNA molecules and then reconnect the strands, relieving strain and effectively preventing tangling and knotting during replication.
The death cap mushroom toxicity can cause inhibition of RNA Polymerase II, the enzyme necessary for synthesis of mRNA. The body must be able to produce mRNA or else there will not be a template to make new protein. “Without mRNA essential protein synthesis and hence cell metabolism grind to a halt and the cell dies.” (Amanita phalloides, “ n.d.) DNA Polymerase are enzymes that catalyze the synthesis of new complimentary strands, occurring at each fork and move from 5’ to 3’. When DNA Polymerase moves along the strands, new DNA is placed. Primase (RNA Polymerase)
The first step of DNA replication is the unwinding of the two individual strands of DNA that are together in a structure that is known as a “double helix”, a term coined by Watson and Crick, who founded the first original model of DNA. The enzyme that is used to split the two strands is called helicase, and the splitting process starts in a place called the “origin of replication”. After each separate DNA strand has successfully unwound, the bases that are present on the strands are now exposed, and unpaired. The enzymes then match the bases with the free nucleotide triphosphates. The bases used in DNA replication are adenine (A), thymine (T), guanine (G), and cytosine (C).
During transcription, RNA polymerase makes a copy of a gene from the DNA to mRNA as needed. This process is similar in eukaryotes and prokaryotes. One notable difference, however, is that prokaryotic RNA polymerase associates with mRNA-processing enzymes during transcription so that processing can proceed quickly after the start of transcription. The short-lived, unprocessed or partially processed, product is termed pre-mRNA; once completely processed, it is termed mature mRNA.  Eukaryotic pre-mRNA processingMain article: Post-transcriptional modification Processing of mRNA differs greatly among eukaryotes, bacteria, and archea.
This is the restriction enzyme and acts as “molecular scissors” cuts the two DNA chains at a specific area in the genome so that sections of DNA can be supplemented or detached. A piece of RNA known as guide RNA is the second key molecule. This consists of pre-designed RNA quite small in length sequence, consisting of about 20 bases, positioned within a longer RNA scaffold. The scaffold binds to DNA and the pre-designed sequence ‘guides’ Cas9 to the right part of the genome. ensuring that the Cas9 enzyme intersects at the right point in the genome.
Transgenesis and Cloning Transgenesis is the process of inserting a gene from one source into a living organism that would not normally contain the inserted gene. The gene can come from the same species (called Cisgenesis) or from a different species entirely. To facilitate the transfer of genes from one organism to another, often a Transgenic Organism with Recombinant DNA is created: -The first step in creating an organism capable of carrying out the transformation process is to isolate the required gene. This is done so using Restriction Enzymes, which target a specific gene sequence. The gene is often cut with staggered ends, called “Sticky Ends” which only allow specific and complementary gene sequences bond by base pairing.
(1) The virus attaches to receptor on a host cell, injecting a genetic material (RNA) and enzymes. (2) A viral enzyme transcribed the RNA in to the same form as the host cell's genetic material(DNA). (3) The viral DNA is integrated into the chromosomes on the nucleus of the host cell. This integrated DNA is called provirus (4) After a long idle period, the provirus directs enzymes in the host cells to produce new strands of viral RNA. The new viral RNA serves as blueprint.
D) One strand is positively charged and the other is negatively charged. E) One strand contains only purines and the other contains only pyrimidines. 17) It became apparent to Watson and Crick after completion of their model that the DNA molecule could carry a vast amount of hereditary information in which of the following? AA A) sequence of bases B) phosphate-sugar backbones C) complementary pairing of bases D) side groups of nitrogenous bases E) different five-carbon sugars 37) What is the function of DNA polymerase III? CC A) to unwind the DNA helix during replication B) to seal together the broken ends of DNA strands C) to add nucleotides to the end of a growing DNA strand D) to degrade damaged DNA molecules E) to rejoin the two DNA strands (one new and one old) after replication 30) Eukaryotic telomeres replicate differently than the rest of the chromosome.