By the end of this lesson, you should be able to: 1. Understand and Illustrate the Primary Structure of Nucleic Acids - Identify and describe the key components
By the end of this lesson, you should be able to: 1. Understand and Illustrate the Primary Structure of Nucleic Acids - Identify and describe the key components of nucleic acids: Phosphate group (P) - Nitrogenous bases (N) (Purines: adenine, guanine; Pyrimidines: cytosine, thymine/uracil). - Pentose sugars (Deoxyribose in DNA; Ribose in RNA). - Draw and label :A nucleotide showing sugar, nitrogenous base, and phosphate groups. - Deoxynucleotide triphosphates (dNTPs) with all three phosphate groups. - RNA nucleotide (rNTP) and compare it with DNA nucleotides. - ATP structure, explaining its role in energy transfer. - Explain how nucleotides are linked by phosphodiester bonds to form the sugar-phosphate backbone. 2. Describe and Illustrate the Secondary Structure - Understand and describe the bonds stabilizing the structure: Hydrogen bonds between complementary bases. - Base pairing rules: A-T (or A-U in RNA) and G-C. - Discuss structural differences between RNA and DNA: RNA : Single-stranded, forms loops and folds (e.g., hairpins). - DNA : Double-stranded helix with antiparallel strands (5’ to 3’ direction). - Draw and label :Single-stranded RNA showing phosphodiester bonds and base pairs. - DNA’s double helix :Include 5’ and 3’ ends. - Show base pairing and antiparallel strand orientation. 3. Explain the Tertiary Structure of DNA - Describe how DNA forms complex 3D shapes: A-DNA : Found under dehydrated conditions; right-handed helix. - B-DNA : Most common in cells; right-handed helix with ~10.5 base pairs per turn. - Z-DNA : Rare, left-handed helix; forms under high salt conditions or during transcription. - Compare shapes, nucleotide arrangement, and functional significance. - Draw and label :Simple representations of A-DNA, B-DNA, and Z-DNA. 4. Discuss the Quaternary Structure - Understand how DNA interacts with proteins to form higher-order structures:Role of histones in forming nucleosomes and chromatin. - Interaction of DNA with other proteins via ionic and hydrogen bonds. - Explain how DNA compacts into chromosomes. 5. Explore the Chemical Properties of DNA - Discuss DNA’s chemical stability due to:Hydrogen bonding between bases. - Hydrophobic interactions within the double helix. - Explain denaturation and renaturation of DNA. 6. Explain DNA Replication - Understand the process of DNA replication:Semiconservative nature of replication. - Directionality of replication (5’ to 3’). - Role of enzymes such as helicase, DNA polymerase, and ligase. - Illustrate :Replication fork showing leading and lagging strands. Practical and Drawing Skills - Draw and label :Nucleotides, ATP, dNTPs, and RNA nucleotides. - DNA and RNA structures, including phosphodiester bonds. - Double helix with antiparallel strands and base pairing. - Illustrate :DNA tertiary structures (A, B, and Z forms). - DNA-protein interaction in quaternary structure. - Key steps in DNA replication. ---