Nucleic Acids - RNA and DNA is a complex, high-molecular- weight biochemical macromolecule composed of chains that convey genetic information. The most common nucleic acids are deoxyribonucleic acid (DNA) and ribonucleic acid (RNA). Nucleic acids are found in all living cells and viruses.

Nucleotides are the building blocks of DNA and RNA. Serve as molecules to store energy and reducing power. The three major components in all nucleotides are phosphoric acid, pentose (ribose and deoxyribose), and a base (purine or purimidine). Two major purines present in nucleotides are adenine (A) and guanine (G), and three major purimidines are thymine (T), cytosine (C) and uracil (U).

Ribonucleotides Adenosine triphosphate (ATP) and guanosine triphosphate (GTP), which are the major sources of energy for cell work. - The phosphate bonds in ATP and GTP are high-energy bonds. - The formation of phosphate bonds or their hydrolysis is the primary means by which cellular energy is stored or used. nicotinamide adenine dinucleotide (NAD) and nicotinamide adenine dinucleotide phosphate (NADP). The two most common carriers of reducing power for biological oxidation-reduction reactions.

Deoxyribonucleic Acid (DNA) Deoxyribonucleic acid (DNA) is formed by condensation of. The nucleotides are linked together between the 3’ and 5’ carbons’ successive pentose rings by p r bonds 3 5

-DNA is a very large threadlike macromolecule (MW, 2X10 9 D in E. coli). -DNA contains adenine (A) and guanine (G), thymine (T) and cytosine (C). -DNA molecules are two stranded and have a double-helical three-dimensional structure. Deoxyribonucleic Acid (DNA)

DNA Double-helical Structure

Double Helical DNA Structure The main features of double helical DNA structure are as follows:. -The phosphate and deoxyribose units are on the outer surface, but the bases point toward the chain center. The plane of the bases are perpendicular to the helix axis. -The diameter of the helix is 2 nm, the helical structure repeats after ten residues on each chain, at an interval of 3.4 nm. -The two chains are held together by hydrogen bonding between pairs of bases. Adenine (A) -, guanines (G) -. - The sequence of bases along a DNA strand is not restricted in any way and carries genetic information, and sugar and phosphate groups perform a structure role.

Regeneration of DNA from original DNA segments. DNA Replication

DNA Replication -DNA helix unzips and forms two separate strands. -Each strand will form a new double strands. -The two resulting double strands are identical, and each of them consists of one original and one newly synthesized strand. -This is called semiconservative replication. -The base sequences of the new strand are complementary to that of the parent strand.

Ribonucleic Acid (RNA) Ribonucleic acid (RNA) is formed by condensation of. RNA is a long, unbranched macromolecule and may contain 70 to several thousand nucleotides. RNA molecule is usually single stranded. RNA contains adenine (A), guanine (G), cytosine (C) and uracial (U). A-U, G-C in some double helical regions of t-RNA.

Classification of RNA According to the function of RNA, it can be classified as: RNA: (m-RNA) synthesized on chromosome and carries genetic information to the ribosomes for protein synthesis. It has short half-life. RNA (t-RNA) is a relatively small and stable molecule that carries a specific amino acid from the cytoplasm to the site of protein synthesis on ribosomes. RNA (r-RNA) is the major component of ribosomes, constituting nearly 65%. r-RNA is responsible for protein synthesis. Ribozymes are RNA molecules that have catalytic properties.

Summary of Nucleic Acids Nucleotides are basic units of nucleic acids DNA and RNA. Nucleotides include pentose, base and phosphoric acid. Bases include purine or pyrimidine. Two major purines present in nucleotides are adenine (A) and guanine (G), and three major pyrimidines are thymine (T), cytosine (C) and uracil (U). Ribonucleotides - adenine triphosphate (ATP) stores energy. - NAD and NADP are important carriers of reducing power.

DNA DNA contains genetic information. DNA contains adenine (A) and guanine (G), and thymine (T), and cytosine (C). A-T G-C DNA has a double helical structure. The bases in DNA carry the genetic information. Summary of Nucleic Acids

RNA RNA functions as genetic information-carrying intermediates in protein synthesis. It contains adenine (A) and guanine (G), and cytosine (C) and uracil (U). m-RNA carries genetic information from DNA to the ribosomes for protein synthesis. t-RNA transfers amino acid to the site of protein synthesis r-RNA is for protein synthesis. Summary of Nucleic Acids

Summary of Cell Construction BiopolymersproteinCarbohydrates (polysaccharides) DNARNAlipids subunit bonds for subunit linkage functions Characteristic three-D structure