1. SBI 4U: Metablic Processes
NUCLEIC ACIDS
Mainly store hereditary information
DNA stores codes for proteins/creating an organism,
RNA reads DNA and helps to build proteins.
Only molecules in existence that are able to identically copy themselves (Interphase)‏
Nucleic Acids are (usually) long polymers of nucleotides
Nucleotides consist of a phosphate group, a pentose and a nitrogenous base.
Nucleotides differ in either their sugar or their nitrogenous base. RNA has ribose, whereas DNA has deoxyribose.
Section 1.3

2. SBI 4U: Metablic Processes
NUCLEOTIDE
Section 1.3

3. SBI 4U: Metablic Processes
DNA uses 4 nitrogenous bases in its nucleotides: Adenine, Guanine, Cytosine and Thymine.
RNA uses 4 as well, but substitutes Uracil in for Thymine
Adenine and Guanine are composed of 2 fused carbon ring structures and are known as purines.
Thymine, Cytosine and Uracil are composed of 1 carbon ring structure and are known as pyrimidines.
DNA is in the shape of an alpha-helix composed of two strands that run antiparallel, which means the phosphate group of one strand is aligned with the sugar in the other strand.
The two strands are held together by hydrogen bonding that occurs between the nucleotides.
Section 1.3

4. SBI 4U: Metablic Processes
Each nucleotide bond contains one purine and one pyrimidine, which keeps DNA a consistent size (about 2 nm).
In DNA Adenine always binds with Thymine since they are both able to make 2 hydrogen bonds and Cytosine always bonds with Guanine since they are both able to make 3 hydrogen bonds.
Section 1.3

5. SBI 4U: Metablic Processes
Nucleotides also do other things:
1) Adenosine Triphosphate (ATP) is the main energy carrying molecule of the cell.
Nicotinamide adenine dinucleotide (NAD+) and flavin adenine dinucleotide (FAD) and electron carrying molecules used in the production of ATP.
NADP+ is used as a coenzyme in photosynthesis.
Cyclic adenosine monophosphate (cAMP) is used as a second messenger in hormone reactions.
Section 1.3