Biology Unit 3 Review Essay

Submitted By laprairie24
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Pages: 10

Unit 3 Review
Chapter 11
1. Describe each of the experiments that demonstrated that DNA is the genetic material.
2. Explain how the contributions of Wilkins and Franklin, Watson and Crick, and Chargaff resulted in understanding the structure of DNA.
3. Describe the importance of covalent bonds and hydrogen bonds to the structure of a DNA molecule.
4. Explain the results of the Meselson-Stahl experiment and describe the predicted results if DNA replication followed the other possible models.
5. Describe the relationship between the structure of a DNA molecule and the means by which DNA is replicated.
6. Outline the basic steps involved in DNA replication, including major differences between eukaryotes and bacteria.
7. List the enzymes used during DNA replication and associate each of the enzymes with their particular function during replication.
8. Explain how eukaryotes overcome the difficulty of replicating the ends of linear chromosomes. ( explain the function of telomerase).
9. Explain the significance of histone proteins, including their charge and amino-terminal tails.
10. Define “nucleosome” and explain its function during DNA compaction.

Chapter 12
1. Describe the flow of information from the genetic material to a functional protein molecule.
2. Describe the evidence for the one-gene/one-polypeptide hypothesis
3. Distinguish between transcription and translation.
4. Explain what the one gene one polypeptide theory is.
a. Beadle and Tatum conclude that single gene controls the synthesis of a single enzyme. –one gene- one gene hypothesis ---- updated to --- one gene- one polypeptide theory
5. Explain the differences between transcription and translation.
a. Transcription= Produces an RNA copy or transcript of a gene; structural genes produce messenger RNA that specifies the amino acid sequence of a polypeptide
b. Translation= Process of synthesizing specific polypeptides on a ribosome. Eukaryotes have additional intervening step called RNA processing where pre-mRNA is processed into functionally active mRNA
6. What is gene expression?
a. Genes contain the information necessary to make the organism and allows it to favorably interact with its environment. Structural genes code for polypeptides. Activities of proteins determine structure and function of cells. Traits or characteristics of organism based on cellular activities.
7. Explain what happens to pre-mRNA molecule during processing.
8. Describe the function of the promoter regulatory sequence, transcribed region, and terminator region.
9. Describe the importance of end modification to eukaryotic mRNA.
10. Describe the roles of the different eukaryotic RNA polymerase.
a. Initiation= recognition step, in bacteria sigma factor causes RNA polymerase to recognized promoter region, catalytic portion of RNA polymerase has similar structure in all species, made in nucleus, 5’ to 3’ direction
b. Elongation= RNA polymerase synthesize RNA after release of sigma factor, open complex 10-15 base pairs long, template or coding strand used for RNA synthesis synthesized 5’ to 3’ uracil substituted for thymine, behind open complex DNA rewinds
c. Termination= RNA polymerase reaches termination sequence, causes it and newly made RNA transcript to dissociate from DNA, stops making RNA, RNA---mRNA prokaryotic in cytoplasm
11. List and explain the sequence of events during transcription of a gene.
12. The process that produces mRNA from DNA is called what?
a. Transcription
13. RNA polymerase is used in what?
a. Transcription
14. Explain what happens to eukaryotic mRNA during capping, splicing, and tailing.
15. Describe the function of the 5’ cap and the 3’ tail.
16. Explain why exons are left in the mRNA and introns are cut out of the mRNA.
17. What is an organized unit of DNA sequences that enables a segment of DNA to be transcripted into RNA and ultimately results in the formation of a functional product?
a. Gene
18. Identify the relationship between codons and amino acids…