DNA
From EvoWiki
Deoxyribonucleic acid (DNA) is one of the four macromolecules important for life. DNA is the principal component of chromosomes, and hence genes and is described as the molecule of heredity. In eukaryotic cells DNA is found in the nucleus as chromosomes, in prokaryotic cells DNA is found in the cytoplasm, usually as circular strands.
Chemical Properties
Each DNA molecule consists of thousands of units, which in turn consist of:
- Sugar-phosphate backbone:
- An organic base, one of: adenine (A), thymine (T), cytosine (C), and guanine (G).
The deoxyribose, phosphate and organic base join to form a nucleotide, the monomer component of a nucleic acid.
These units repeat thousands of times to form a polynucleotide. Adenine is able to form intermolecular bonds with thymine, and cytosine with guanine and in this way two polynucleotide chains join together with opposing A-T and G-C pairs to form a double helix.
The DNA thread is then folded and wrapped around proteins allowing the very long chain to be stored in a cell.
To Do List
- Replication
- Role: Codons, gene expression etc
- 'Junk' DNA
- Brief history
