Question

1. Know the structure of DNA and RNA 2. Know the major research that led to the discovery of DNA's structure and its' role as the genetic material 3. Describe DNA replication in detail-include licensing and termination factors Describe the role of histones in chromatin packaging and gene regulation 5. Explain the role of transcription factors in gene expression 6. Explain transcription and translation in detail. 7. Know how mutations occur. 8. Know all the types of mutations 9. Know how mutations affect the products of transcription 10. Know the catalytic roles of RNA 11. Be able to describe the reproductive strategies of the 6 classes of viruses 12. Describe the basic morphology of viruses 13. Explain the difficulties with viral phylogeny and their origins 14. Describe the basic genetic control mechanisms for the lytic and lysogenic cycles of the lambda phage 15. Know the repair mechanisms of DNA 16. Explain eukaryotic transcription and translation in detail, 17. Know how mutations occur. 18. Know all the types of mutations 19. Describe the basic morphology of viruses 20. Know the mechanisms of bacterial transformation, conjugation and transduction 21. Know what prions and yiroids are 22. Describe how inducible and repressible operons work in anabolic and catabolic pathways in bacteria 23. Describe positive gene regulation in bacteria 24. Be able to describe: A why prokaryotes evolve rapidly

Answer 1

1. Know the structure of DNA and RNA

SOLUTIONS-

DNA- Refers to De-oxy ribonucleic acid, core genetic materials for living organisms.

LOCATION- Nucleus, Mitochondria etc.

STURUCTURE- Year 1953 almost after 100 years of first isolation of DNA (1869) by swiss physician Friedrich Miescher, James Watsons and Francis Crick described and revealed the double helix structure of DNA.

                COMPONENTS- a. Sugar or Deoxyribose. b. Phosphate, c. Base 2 Pyrimidines and 2 purine (Adenine-A, Guanine-G, Cytosine-C, Thymine-T), d. Hydrogen bond between bases.

                CONSTITUTIONS- Two chain or strand intertwined to form a complete double-helix structure of DNA. Each strand is made up of nucleotide each nucleotide is made up by a sugar, a base, a phosphate group. Phosphate group is attached with 3’-carbon of one deoxyribose sugar and with 5’-carbon of another to made a complete strand. The two strands are oriented in opposite directions. 3’-5’ with another 5’-3’, means 3’ end of one strand is corresponding with 5’ end of opposite strands.

                A sugar/deoxy ribose molecule and nitrogen base known as nucleoside. A nucleoside with phosphate group known as nucleotides. [ SUGAR+BASE- NUCLEOSIDE; NUCLEOSIDE+PHOSPHATE- NUCLEOTIDE]. This deoxyribose has free hydroxyl groups on carbon 2’, 3’ and 5’ although in almost all cases phosphate attached in position 3’ and 5’. And base in attached in 1’ carbon position to make a complete nucleotide.

                Two corresponding strands is attached with each other by hydrogen bonds between purine (Adenine and guanine ) and pyrimidine (Cytosine and Thymine) bases. Adenine +Guanine= Cytosine + Thymine ratio. In this way make a double helix complete DNA structure.

RNA- Refers to Ribonucleic acid. Cellular protein synthesis is the main function of RNA.

LOCATION- Everywhere within the cell.

HOSPHATE BASE BASE OF 4-0 o=a-o PHOSPHATE PHOSPHATE BASE PYRIMIDINE I HYHINE CYTOSINE PURING ADINING GUANINE SUGAR DE OXIRIBOSE RIBOSE HOCH2. O OH HOCH₂ o. OH SH HOH STRUCTURE c-H3 2004 -H3 1 THYM o-Bo - - - - --4 A • Pro SUGAR O Althy 3.00u. Y TO op=o SININ I 8.-N.COM FULL CHAIN SUGAR)

STRUCTURE- As per as components is almost same as DNA but instead of deoxyribose sugar it contain ribose sugar, instead of phosphate linkage they have phosphodiester. And in base it contain adenine, guanine, cytosine and uracil(replace thymine).

It is a single strand biopolymer, although they can be situated in folding or any complex formation. As per as strand structure is concern, it is same as DNA but there is no hydrogen bond between to base pair as they are not a conventional double helix structure. But there is a difference in fine structure between different types of available RNA. They are like – mRNA(Messenger RNA), tRNA(transfer RNA), rRNA(raibosomal RNA).