Nucleic Acid

• Enzyme action speeds up as the temperature increases because reactants have more kinetic energy at higher temperature.
• Temperature measures the energy of molecular motion.
• All molecules move and move faster as they absorb heat.
• An enzyme action is needed to increase the reaction but if the enzyme becomes too hot, it denatures and cannot function anymore.
• Body temperature above the normal temperature greatly affects the function of many of our enzymes that is why severe fevers are dangerous.
• Most of our enzymes work best when our body fluids are between pH 6 and 8 but for pepsin, a digestive enzyme in our stomach works best between pH 1 and 2.
• Pepsin begins protein digestion in our stomach with a pH of 2 which is very acidic.
• The food passes into the small intestine where the pH rises to 9.
• Pepsin denatures above pH 5.5 so it deactivates in the small intestine but digestion continues with the aid of another enzyme, trypsin which can tolerate a high pH.
• Nucleic acids are complex macromolecules which store information that determine the type and structure of all specific proteins found in an organism’s body.
• Nucleic acids are polymers made up of monomers called nucleotide.
• Each nucleotide is composed of three components which are covalently bonded together: a phosphate molecule, a five carbon sugar (Pentose), and a nitrogen containing base.
• There are two kinds of nucleic acids: Deoxyribonucleic acid (DNA) which carries instruction that controls the activities of a cell and is located inside the nucleus of the cell, and Ribonucleic acid (RNA) which uses instructions to make proteins and is named after the ribose sugar found in the molecule’s backbone.
• There are three types of RNA: Messenger RNA (mRNA) which transmits genetic instructions coded in the DNA inside the nucleus to the cytoplasm particularly in the ribosome where it is translated into amino acids to produce proteins, Transfer RNA (tRNA) which is found in the cytoplasm of the cell and translates the codon of mRNA into amino acids by attaching amino acids to the ribosomes facilitating protein synthesis, and Ribosomal RNA (rRNA) which is the protein factory of the cell and are abundant in the cytoplasm.