Structure and Composition

1. Structure and Composition DNA is sometimes called "the blueprint of life" because it contains the code, or instructions for building and organizing and ensuring that organism functions correctly.

2. DeoxyriboNucleic Acid • DNA is composed of subunits called nucleotides, strung together in a long chain • Each nucleotide consists of: a phosphate, a sugar (deoxyribose), and a base

3. Bases • Bases come in two types: pyrimidines (cytosine and thymine) • and purines • (guanine and adenine)

4. The sugar and phosphates make up the "backbone" of the DNA molecule.

5. The shape of the DNA molecule is a double-stranded helix (like a twisted ladder). • The sides of the ladder are composed of alternating sugars (deoxyribose) and phosphates. • The rungs of the ladder are composed of nucleotides. James Watson & Francis Crick

6. Base Pair Rule • Nucleotides pair in a specific way - called the Base-Pair Rule • Adenine always pairs • with Thymine (A-T) • Guanine always pairs • with Cytosine (C-G)

7. Base Pair Rule

8. Here are some bases of DNA: • A -A-T-G-T-A-T-A-C-A-A-G-G-C-A-T • Now match them with their complementary bases.

10. RNA • RNA is like DNA • It stands for Ribonucleic Acid • It’s used to make proteins, whereas DNA contains the information of life

11. What are some differences?

12. What are some Differences?