University:
York University
Course:
SC/BIOL 2021 | Cell Biology
Academic year:

2023
Views:

318

Pages:

2
Author:

Nick T.

Nucleic Acids: Narrower range of function Information molecules with DNA and RNA Polymers Monomer: Nucleotides: Small repeating subunits Complementary base pairs: Adenine + Thymine (2 H-bonds) Cytosine + Guanine (3 H-bonds) Structure of Nucleotides (3 Parts): Nitrogenous Base Phosphate Group Pentose Sugar Components: Pyrimidines (smaller rings): Cytosine, Thymine, Uracil Purines (bigger rings): Guanine and Adenine Pentose (2 kinds): DNA: HOCH₂ - OH - H - OH - H - OH RNA: HOCH₂ - OH - H - OH - OH Nucleotides vs. Nucleosides: Nucleotide: Ribose + Base + Phosphate Nucleoside: Ribose + Base Functions of Nucleotides: Act as coenzymes or cofactors Agents in energy transfer Signal molecules Link via condensation reactions Phosphodiester Linkage: Makes up the backbone of nucleic acids Links sugars to phosphates from 3' carbon on one sugar to 5' end of another Nucleotides can be added here Polymerization (Endergonic): Makes new P-D bonds from 2 nucleotides Through input of energy Addition of 3 phosphates DNA (Deoxyribonucleic Acid): Deoxyribose sugar Doesn't contain hydroxyl group A-T pairing Double helix (double stranded) More stable Thymine RNA (Ribonucleic Acid): Ribose sugar Has a hydroxyl group A-U pairing Single stranded More unstable Uracil Both DNA and RNA: H-bonds between complementary base pairs Phosphodiester linkages between sugars and phosphates to create a backbone DNA Reading Direction: DNA is read 5' to 3' To get the other strand, find complementary base pairs and invert the order