Difference between oxidation and reduction state?
Oxidative phosphorylation
If energy for phosphorylation comes from the breakdown of organic molecules in a cell is called oxidative phosphorylation. e.g., the formation of ATP during cellular respiration.
Dinucleotide
Dinucleotide (Nicotinamide adenine dinucleotide NAD) Most enzymes need additional chemical
components to become functional called cofactors. Cofactors may be inorganic or organic but other than proteins are known as coenzymes e.g., nicotinamide adenine dinucleotide (NAD) and many vitamins.
Structure of NAD:
NAD consists of two nucleotides, one consists of nicotinamide base, sugar, and phosphate group, Other consists of adenine base, sugar, and phosphate group. Both nucleotides are linked by their phosphate group forming a dinucleotide. NAD is derived from nicotinic acid or niacin (vitamin B).
In metabolism, NAD is involved in redox reactions, carrying electrons from one reaction to another. This co-enzyme is, therefore, found in two forms in cells. NAD is an oxidizing agent. It accepts two energetic electrons and a proton from other molecules and becomes reduced (NADH), which can be used as a reducing agent to donate electrons.
These electron transfer reactions are the main function of NAD. Another example of dinucleotide is flavin adenine dinucleotide (FAD) which is also a co-enzyme sometimes used instead of NAD. It
accepts two electrons (reduced) and two protons to become FADH2.
Deoxyribonucleic acid (DNA):
Deoxyribonucleic acid is a polymer of deoxyribonucleotides found mostly in the nucleus, with few traces in the mitochondrion and chloroplast. It contains instructions, that an organism needs to develop, live, and reproduce.
Discovery:
Nucleic acid was first observed by a Swiss biochemist named Friedrich Meischer in 1869. However, for a long time, researchers did not find its exact structure and function. It was not until 1953 that James Watson, Francis Crick, Maurice Wilkins, and Rosalind Franklin figured out the structure of DNA (double helix).
Watson, Crick, and Wilkins were awarded the Nobel Prize for Medicine in 1962 for giving comprehensive information on the structure and importance of DNA.
DNA structure :
DNA is made up of molecules called deoxyribonucleotides. Each nucleotide
consists of a deoxyribose sugar, a phosphate group, and a nitrogen-containing base. There are four types of bases, two purine bases (Adenine and guanine) and two pyrimidine bases (Thymine and cytosine).
The order of these nitrogenous bases determines DNA's instructions for protein synthesis.
The nucleotides are attached together to form two long strands that twist to create a double helix structure, running in opposite directions antiparallel and winding about each other like a circular ladder. The phosphate and sugar molecules make the sides (upright) while the bases make rungs.
The bases on one strand pair with the bases on another strand in a specific manner. Adenine always pairs with thymine and cytosine with guanine.
Structure of Ribonucleic Acid (RNA):
RNA is a long unbranched polymeric molecule formed by the interlinkage of four monomeric units known as ribonucleotides of adenine, guanine, cytosine, and uracil bases.
RNA molecules are single-stranded, except for the Reovirus. However, some RNA molecules have regions in which hydrogen bonds between A = U and G =C bases are formed between different regions of the same molecule thus coiled itself looks like double-stranded hairpin loops.
RNA is mostly present in cytoplasm but synthesized within the nucleus by using only one strand of DNA as a template (3-5') direction. Thus it is a true copy of the genetic information contained in DNA. RNA helps DNA in protein synthesis. In some animal and all plant viruses, RNA functions as hereditary material. The amount of RNA varies from cell to cell.
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