L11 DNA - Chapter 11 Lecture Guide A Closer Look at DNA I....

Info iconThis preview shows pages 1–3. Sign up to view the full content.

View Full Document Right Arrow Icon
Chapter 11 Lecture Guide A Closer Look at DNA I. History a. James Watson and Francis Crick determined the structure for DNA (1953). b. Used the help of Rosalind Franklin: an X-ray crystallographer II. Structure a. Nucleotides are the building blocks of DNA (and RNA) i. 3 components 1. Phosphate group 2. Pentose sugar 3. Nitrogenous base b. Two strands form a double helix—a ladder-like structure i. Sugar-phosphate forms the backbone ii. Nitrogenous base pairs form the “rungs” on the ladder a. Purines: guanine (G), adenine (A) b. Pyrimidine: cytosine (C), thymine (T) c. Antiparallel strands d. Hydrogen bonds e. Covalent bonds 1
Background image of page 1

Info iconThis preview has intentionally blurred sections. Sign up to view the full version.

View Full DocumentRight Arrow Icon
Chapter 11 Lecture Guide f. Conventional numbering system i. Sugar carbons 1’ to 5’ ii. Base attached to 1’ iii. Phosphate attached to 5’ III. Facts a. Each human cell has 46 DNA molecules in its nucleus—one double helix per chromosome i. That’s 6 billion base pairs ii. The DNA of a human being is organized in threads. If you stretched out these threads end to end, they’d be 5 feet long and 50 trillionths of an inch wide. b.
Background image of page 2
Image of page 3
This is the end of the preview. Sign up to access the rest of the document.

This note was uploaded on 10/28/2011 for the course BIO 183 taught by Professor Parks during the Spring '07 term at N.C. State.

Page1 / 8

L11 DNA - Chapter 11 Lecture Guide A Closer Look at DNA I....

This preview shows document pages 1 - 3. Sign up to view the full document.

View Full Document Right Arrow Icon
Ask a homework question - tutors are online