Basically, DNA controls protein synthesis. The complex and precise process of protein synthesis begins within a gene, which is a distinct portion of a cell's DNA. DNA is a nucleic acid which is made up of repeating monomers, called nucleotides, and in the case of DNA, these individual monomers consist of a pentose sugar, a phosphoric acid and four bases known as adenine, guanine, cytosine and thymine. DNA is a double stranded polymer, which has a twisted ladder like
Each genome contains the information needed to maintain and create the organism. The process of genetic engineering involves extracting of a small piece of cellular DNA, called a plasmid, from the bacteria if organism involved in the manipulation. A very small section of the circular plasmid is then cut out by the restriction enzymes which act as molecular scissors. The gene from the organism being modified is then inserted into this space and the plasmid is therefore modified. The genetically modified plasmid is now inserted and introduces into a new organism which starts divides rapidly.
The bases used in DNA replication are adenine (A), thymine (T), guanine (G), and cytosine (C). In RNA, uracil (U) is used instead of thymine, but in this case, that is irrelevant. Generally, in a normal human being, A is matched up with T, and G is matched up with C to makeup the complementary base pairs. An important step in the initiation of the replication process is the binding of the RNA primase. This primase attracts the nucleotides that bind to the corresponding nucleotides of the 3’-5’ strand.
Test your knowledge Match the correct functions For each of the enzymes in questions, 1-5, choose an answer (a-e) that most closely describes the functions of the enzymes Question 1 helicase Question 2 DNA polymerase 1 Question 3 ligase Question 4 DNA polymerase 111 Question 5 RNA polymerase Answers (a) removes the RNA primers during replication (b) performs transcription (c) unwinds DNA for DNA replication (d) adds nucleotides during DNA replication (e) forms phosphodiester bonds between Okazaki fragments Question 6 Which of the following are the nucleotides found in RNA (a) A, C, G, T (b) A, C, G, U (c) T, C, G, U (d) A, T, G, U (e) U, C, T, A
DNA and its close relative RNA are perhaps the most important molecules in biology. They contains the instructions that make every single living organism on the planet. DNA stands for deoxyribonucleic acid and RNA for ribonucleic acid. They are polymers (long chain molecules) made from nucleotides. Nucleotides Nucleotides have three parts to them: • a phosphate group, which is negatively charged.
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.