RNA primase lays the beginning for DNA Primase to begin laying down the nucleobases: Adenine, Thymine, Cytosine and Guanine. 3. Okazaki fragment from RNA primase a segment of the lagging strand during replication. 4. DNA ligase goes over all the small Okazaki segments and binds them into a new strand of DNA.
The nucleotide sequence on the template strand of the gene. ACA b. The mRNA codon that results after this triplet code is transcribed. UCU c. The anticodon on the tRNA molecule that is complementary to the mRNA codon described above. AGA d. The amino acid that would be carried by the tRNA molecule described above.
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 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).
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.
Replication Fork In the DNA double helix Topolisomerase relieves the tension. When Helicase breaks down the hydrogen bonds replication begins. Replication can take place in 2 directions because of the replication bubble. The enzyme Primase synthesizes the RNA primers. There has to be primers to start the synthesis at the 3’ end of the new strands.
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.
Proteins are formed through condensation reactions which bond amino acids together with peptide bonds in a particular sequence and the type of protein that is created is defined by the unique sequence of the amino acids. DNA and RNA are nucleic acids that are formed in the nucleotides and are both involved in the process of protein synthesis. Deoxyribonucleic acid, more commonly known as DNA, is located within the nucleus of the cell and contains the entire genetic code for an organism within its structure. DNA has two very important functions which are: to convey information from one generation of cells to the next by the process of DNA replication and to provide the information for the synthesis of proteins necessary for cellular function. Basically, DNA controls protein synthesis.
Interpahse includes the G1, S, and G2 phases of the cell cycle. Cells in interpase grow and undergo the various metabolic processes needed for their functioning during G1, S, and G2. Mitosis has 4 major stages -Prophase, Metaphase, Anaphase, and Telophase. During interphase, DNA replication occurs. After duplication the cell is ready to begin mitosis.