Question

DNA EXTRACTION AND THE CENTRAL DOGM 7. The two molecules that form the sides of the 8. The chemical bonds joining complementary 9. The chemical bonds joining one nucleotide to ? DNA ladder another (sides of the ladder) B. REVIEW OF DNA REPLICATION: FILL IN 10. Cellular location of DNA replication in eukaryotes 11. Sites within DNA where replication begins 12. Method of DNA replication 13. DNA strand that is synthesized in a 0 continuous manner 14. Stage of the cell cycle when DNA replication occurs 15. Product of DNA replication C. REVIEW OF RNA STRUCTURE AND 16. Name of the sugar found in RNA 17. Number of strands in RNA 18. List the three types of RNA involved in protein synthesis 19. The template for RNA synthesis 20. Term for synthesis of RNA 21. Cellular location of RNA synthesis in eukaryotes D. TRANSLATION OF RNA TO A PROT 22. The organelle needed for translation and joining of amino acids together 23. Which RNA carries the instructions from DNA to the cytoplasm 24. Which RNA brings in amino acids? 25. Cellular location of protein synthesis

Answer 1

7. Nucleotides are composed of a nitrogenous base(Adenine, thymine, cytosine, guanine), a five-carbon sugar ribose or deoxyribose and a phosphate molecule.The molecules that form the sides of DNA ladder are phosphate molecule and the sugar molecule while the nitrogenous base occupies the middle position where they are stacked together.

8. The complementary nitrogenous bases are bound through hydrogen bonding. The reason behind the twisted nature of double-stranded DNA is the existence of hydrogen bonding. Hydrogen bond forms between a hydrogen atom and a highly electronegative atom such as nitrogen, oxygen, and fluorine. Adenine pairs with thymine through two hydrogen bonds while guanine pairs with cytosine through three hydrogen bonds.

9. One nucleotide connects with another nucleotide through a phosphodiester bond that is created between 3^' carbon of one sugar molecule with 5^' carbon atom of another nucleotide.

10. Eukaryotic DNA replication occurs inside the nucleus.

11. DNA replication begins at the origin of replication, a DNA sequence where replication is initiated. Prokaryotes possess a single origin of replication whereas eukaryotes have multiple origins of replication.

12. There are three methods of DNA replication:

Conservative replication in which entire original double helix act as a template creating one daughter molecule with full parental DNA and the other is completely new.

Semiconservative replication in which double helix are separated and each strand serve as a template for making a new complementary strand thereby conserving half of the parental DNA in each DNA molecule synthesized.

Dispersive replication where some segment of the original double helix is conserved while others are not.

13. Leading strand is synthesized in a continuous manner and in the same direction as that of growing replication fork.

14. DNA replication occurs in the S-phase of the cell cycle that occurs after G1 and prior to the G2 phase of the cell cycle.

15. The product of DNA replication is two identical double-stranded DNA where one strand retains the parental DNA while the other is newly generated. This suggests that DNA replication is semi-conservative.

16. Ribose sugar, a five-carbon sugar is present in RNA.

17. RNA is typically single-stranded but sometimes they may layer upon itself to create double strand as in tRNA. However, in viruses RNA can exist in single or double-stranded form.

18. mRNA, tRNA, and rRNA.

19. A single strand of DNA serves as a template for RNA synthesized facilitated by RNA polymerase.

20. Transcription.

21. Nucleus.

22. Ribosome.

23. mRNA carries the instruction from the DNA to the ribosome in the cytoplasm.

24. tRNA supply an amino acid to the ribosome so that it can be incorporated into the growing chain during protein synthesis.

25. Protein synthesis in both prokaryotes and eukaryotes occur in the cytosol on the ribosome.