Chapter 11 - Chapter 11-Nucleic Acids: Information Storage...

Info iconThis preview shows pages 1–2. Sign up to view the full content.

View Full Document Right Arrow Icon
Chapter 11—Nucleic Acids: Information Storage and Transmission Basics o Genes are the units of heredity and are made of nucleic acid (DNA). o Nucleic acids are polymers of nucleotides linked together by dehydration synthesis reactions. o Nucleotides are the building block molecules of a nucleic acid and are composed of a sugar, a phosphate group, and a nitrogenous base. The sugar and phosphate groups form the nucleic acid backbone. Nucleic acid backbone has directionality (3’ v. 5’) o If DNA were compared to a book, the sugar and phosphate groups would only be the binding of the book. The actual words or genetic information would be contained in the nitrogenous bases . There are 2 families of nitrogenous bases: 1) Pyrimidines —nitrogenous bases characterized by a 6-membered ring made up of carbon and nitrogen atoms. o Thymine and Cytosine 2) Purines —nitrogenous bases characterized by a 5-membered ring fused to a 6- membered ring where both rings are made up of carbon and nitrogen atoms. o Adenine and Guanine o Evidence that DNA is the genetic material: In a eukaryotic cell, the DNA content doubles prior to cell division. During cell division the doubled DNA is divided equally between the two daughter cells. Chargaff’s Rules o In 1947, Erwin Chargaff from Columbia University used paper chromatography to separate the bases of the DNA from different species (fish, humans, bacteria, etc.). Found that the base composition (number of As, Ts, Gs, Cs) varied between species. o
Background image of page 1

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

View Full DocumentRight Arrow Icon
Image of page 2
This is the end of the preview. Sign up to access the rest of the document.

Page1 / 4

Chapter 11 - Chapter 11-Nucleic Acids: Information Storage...

This preview shows document pages 1 - 2. Sign up to view the full document.

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