DNA vs RNA: Structure Showdown

How do DNA and RNA shape life? Exploring the Building Blocks of Life Grade 11 Biology Understanding Nucleic Acid Structures

Learning Objectives: I Can Statements

I can identify the key components of DNA and RNA molecules I can explain the structural differences between DNA and RNA I can describe base pairing rules for both nucleic acids I can compare the functions of DNA and RNA in cells

DNA Structure: The Double Helix

Double-stranded helical structure Sugar: Deoxyribose Phosphate backbone Four bases: A, T, G, C Antiparallel strands

RNA Structure: The Single Strand

Single-stranded structure Sugar: Ribose Phosphate backbone Four bases: A, U, G, C Can fold into complex shapes

DNA vs RNA: Key Structural Differences

{"left":"DNA: Double-stranded\nRNA: Single-stranded\nDNA: Deoxyribose sugar\nRNA: Ribose sugar\nDNA: Thymine (T)","right":"RNA: Uracil (U)\nDNA: Very stable\nRNA: Less stable\nDNA: Larger molecule\nRNA: Smaller molecule"}

Base Pairing Challenge

Match the complementary bases: DNA: A pairs with ___ DNA: G pairs with ___ RNA: A pairs with ___ RNA: G pairs with ___ Work with a partner to complete!

Base Pairing Rules Explained

DNA: A always pairs with T (2 hydrogen bonds) DNA: G always pairs with C (3 hydrogen bonds) RNA: A always pairs with U (2 hydrogen bonds) RNA: G always pairs with C (3 hydrogen bonds) Complementary base pairing ensures accurate replication

Think-Pair-Share Question

Why might RNA's single-strand structure be advantageous for its cellular functions? Think: 30 seconds individually Pair: Share with a neighbor Share: Volunteers share with class

DNA and RNA Functions in the Cell

Success Criteria & Next Steps

✓ Can identify DNA and RNA components ✓ Understand structural differences ✓ Know base pairing rules ✓ Connect structure to function Extension: Research RNA interference (RNAi) Accommodation: Visual summary sheets available