Double Helix structure of DNA
- 1. DOUBLE HELIX STRUCTURE OF DNA Presented By : Prashi Jain Roll No. : MCA/25022/18
- 2. DNA DNA – A polymer of deoxyribonucleotides. Found in chromosomes, mitochondria and chloroplasts. It carries the genetic information used in the growth , development , functioning, and reproduction of all known organisms and many viruses.
- 3. DNA (DEOXYRIBOSE NUCLEIC ACID): STRUCTURE • DNA IS DOUBLE STRANDED MOLECULE THAT IS TWISTED INTO A HELIX (SPIRALLING STAIRCASE). DNA Double helix
- 4. DNA STRUCTURE • PRIMARY STRUCTURE • SECONDARY STRUCTURE • TERTIARY STRUCTURE
- 5. DNA STRUCTURE: PRIMARY STRUCTURE CONSISTS OF A LINEAR SEQUENCES OF NUCLEOTIDES. LINKED TOGETHER BY PHOSPHODIESTER BONDS. • NUCLEOTIDES CONSISTS OF THREE COMPONENTS: 1. NITROGENOUS BASE ADENINE GUANINE CYTOSINE THYMINE (PRESENT IN DNA ONLY) 2. 5-CARBON SUGAR WHICH IS CALLED DEOXYRIBOSE (FOUND IN DNA) AND RIBOSE (FOUND IN RNA). 3. ONE OR MORE PHOSPHATE GROUPS.
- 6. Each strand consists of :- 1-nitrogeneous base -Adenine -Guanine - Cytosine - Thymine 2- A Sugar phosphate backbone
- 7. DNA STRUCTURE MADE UP OF MOLECULES CALLED NUCLEOTIDES COMPONENTS OF A NUCLEOTIDE BASE SUGAR PHOSPHATE
- 8. THE SECONDARY STRUCTURE OF DNA • TWO ANTI-PARALLEL POLYNUCLEOTIDE CHAINS WOUND AROUND THE SAME AXIS. • SUGAR-PHOSPHATE CHAINS WRAP AROUND THE PERIPHERY. • BASES (A, T, C AND G) OCCUPY THE CORE, FORMING COMPLEMENTARY A · T AND G · C WATSON-CRICK BASE PAIRS.
- 9. THE DNA DOUBLE HELIX IS HELD TOGETHER MAINLY BY- HYDROGEN BONDS HYDROGEN BOND A CHEMICAL BOND IN WHICH A HYDROGEN ATOM OF ONE MOLECULE IS ATTRACTED TO AN ELECTRONEGATIVE ATOM, ESPECIALLY A NITROGEN, OXYGEN, OR FLUORINE ATOM, USUALLY OF ANOTHER MOLECULE.
- 10. DNA TERTIARY STRUCTURE DNA DOUBLE HELICAL STRUCTURE COILS ROUND HISTONES. NUCLEOSOMES (10NM FIBRES) •NUCLEOSOMES CONTAIN 146 NUCLEOTIDES
- 11. FUNCTIONS OF DNA 1- GENETIC INFORMATION: DNA IS THE GENETIC MATERIAL WHICH CARRIES ALL THE HEREDITY INFORMATION. 2- REPLICATION: DNA HAS UNIQUE PROPERTY OF REPLICATION OR PRODUCTION OF CARBON COPIES. 3- MUTATIONS: CHANGES IN SEQUENCE OF NITROGEN BASES DUE TO ADDITION, DELETION OR WRONG REPLICATION GIVE RISE TO MUTATIONS. 4- DIFFERENTIATION: DUE TO DIFFERENTIAL FUNCTIONING OF SOME SPECIFIC REGIONS OF DNA OR GENES, DIFFERENT PARTS OOF THE ORGANISMS GET DIFFERENTIATED IN SHAPE, SIZE AND FUNCTIONS.
- 12. APPLICATIONS OF DNA SCIENCE AND TECHNOLOGY HAVE ADVANCED SINCE THE DISCOVERY IN YEAR 1953. SOME ACHIEVEMENTS THAT POTENTIALLY BECAME SUCCESSFUL DUE TO ITS INVENTION. • CLONING • GENETICALLY MODIFIED FOODS (GMFS) • GENETIC ENGINEERING • DNA FINGERPRINTING ANALYSIS
- 13. THANK YOU