Lab 1
· DNA is made up of deoxyribonucelotides
· Components of DNA/RNA includes a 5 carbon sugar, a phosphate group, and a nitrogenous base
· the negative charge associated with DNA/RNA is due to the phosphate groups
· DNA is linked together by phosphodiester bonds (they are covalent bonds)
· the energy required to create these bonds is from the cleavage of pyrophosphate, refer to figure 1.3 on page 4 and below.
· a proton also leaves, water is produced
· the phosphodiester linkage is between the 3’ hydroxyl group and the phosphate attached to the 5’ carbon of the incoming deoxyribonucelotides.
· DNA Polymerase catalyzes this reaction
· The finished covalent bond is called a 3’,5’-phosphodiester bond
· DNA is always arranged in the anti conformation, not syn. - The difference between the two conformations is their angles, an anti conformation has an angle of between 90 and 180, syn has angle of between 0 and 90. (Not required). Refer to figure 1.6 on page 7
· DNA is antiparallel, this means that the 3’ end of the template is across from the 5’ end of the complementary strand.
· the end with the unreacted phosphate group is always the 5’ end.
· Extraction of DNA from strawberry
· DNA is wound around histones (+ charge)
· Histones allow the DNA to fold into chromatin
· NaCl was first added to the mixture because following the disassociation of NaCl into the Na+ will displace the proteins out of the DNA and into the solution, because they are more charged and more polar
· DNA in the presence of sodium becomes highly soluble; this is because DNA, along with water are both polar.
· To extract the DNA, isopropanol was added which decreased the polarity of the solvent. The DNA was then extracted by allowing the DNA to wind around a glass rod.
· Strawberries were used because they are polyploids, meaning they