Download Deoxyribonucleic Acids DNA

Chapter 12 Deoxyribonucleic Acids 2 Cornell Questions
Chromosomes- A threadlike linear strand of DNA and associated
proteins in the nucleus of eukaryotic cells that carries the genes
and functions in the transmission of hereditary information.
In prokaryotes (bacteria) it is a circular strand of DNA in that
contains the hereditary information necessary for cell life.
DNA is made up of 2 strands of the bases guanine, adenine,
thymine, and cytosine, covalently bonded. The 2 strands are
complementary, (side-by-side in opposite directions).
The four nitrogen-containing bases found in DNA are divided into
two groups: purines and pyrimidines. Stopped here 1st per
Adenine and guanine are two-ringed bases called purines.
Thymine and cytosine are One-ringed bases called pyrimidines.
Each strands forms helix, and the two helices are held together
through hydrogen bonds, ionic forces, forming a double helix.
The Structure of DNA
Cornell Style Notes with 3 Questions
DNA is a long molecule made up of units called nucleotides. Nucleotides
are made up of three basic components: a 5- carbon sugar called
deoxyribose, a phosphate group and a nitrogenous base, (nitrogencontaining base).
There are four kinds of nitrogenous bases in DNA, two are purines
adenine and guanine, and two are pyrimidines, thymine and
cytosine.
The back bone of a DNA chain is formed by sugar and phosphate groups
of each nucleotide.
Transparency #173 nucleotide pairing draw below.