AP12 - Biochemistry (Nucleic Acids)

Major Functions of Nucleic Acids

• transmit inherited information (genes) from generation to generation

• determine what proteins a cell makes (instructions on how to assemble proteins)

• allow energy to flow in cells (ATP)

2 classes of polymers

• Ribonucleic acid

• Deoxyribonucleic acid

• polymers formed from monomers called nucleotides (subunits)

DNA

Deoxyribonucleic acid

• transmission of genetic information to next generation

RNA

• ribonucleic acid: needed for protein synthesis

3 parts to a nucleotide

• a 5-carbon ribose sugar

• a phosphate group (Po4)

• a nitrogenous base (cytosine, guanine, thymine, adenine)

pyrimidines

thymine, cytosine

(one ring)

purines

adedine, guanine

(two rings)

Nucleotides

link into very long polymers through dehyration synthesis

• The Ho and H attached to the nucleotides bond to create water and a new covalent bond is formed between the two nucleotides

RNA vs. DNA

• rna has only 1 strand

• dna is double stranded and forms a coil shape called a helix (double helix)

  • the two strands are held together by hydrogen bonds that form between certain pairs of complementary bases

ATP

• Adenosine triphosphate

• The “energy currency” of the cell

• Phosphate bonds require a lot of energy to make

  • due to

Phosphate bonds in ATP (6)

• High-energy bonds are broken, releasing energy, which is used by the body’s chemical reactions

• ATP molecules release energy, which is then used to drive your metabolic reactions

  • ATP → ADP + P + energy

• These bonds are recharged when the body digests sugar

  • 1 glucose molecule has enough energy to recharge 38 ATP molecules

  • ADP + P + energy → ATP