Bio 181, Fall 2004

Learning Objectives for Chapter 17, From Gene to Protein

Understand and be able to use the following terms:

Central Dogma	gene expression	transcription	messenger RNA (mRNA)
primary transcript	RNA processing	triplet code	genetic code
codon	translation	template strand
reading frame	RNA polymerase	promoter	terminator
transcription unit	transcription factors	transcription initiation complex	TATA box
5’ cap	poly-A tail	RNA splicing	introns
exons	snRNPS	splicesosome	ribozymes
alternative splicing	protein domains	transfer RNA (tRNA)	anticodon
wobble	aminoacyl-tRNA synthetases	ribosome	ribosomal RNA (rRNA)
P site	A site	E site	initiation
elongation	translocation	termination	polyribosome
posttranslational modifications	signal peptide	signal recognition particle (SRP)	mutations
point mutations	base-pair substitution	substitution	missense mutations
nonsense mutations	insertion	deletion	frameshift mutation
mutagens

1. Explain the reasoning that led Archibald Garrod to first suggest that genes dictate phenotypes through enzymes.
2. Describe Beadle and Tatum's experiments with Neurospora and explain the contribution they made to our understanding of how genes control metabolism.
3. Distinguish between the "one gene-one enzyme" hypothesis and the "one gene-one polypeptide" hypothesis and explain why the original hypothesis was changed.
4. Explain how RNA differs from DNA.
5. Be able to diagram the flow of genetic information within a cell (the Central Dogma).
6. Distinguish between transcription and translation. Compare where transcription and translation occur in prokaryotes and in eukaryotes
7. Give the fundamental features of the genetic code. What is it? What is a codon? How is the genetic code read? In what direction along a nucleotide is the genetic code read?
8. Explain the relationship between the linear sequence of codons on mRNA and the linear sequence of amino acids in a polypeptide.
9. Explain the early techniques used to identify what amino acids are specified by the triplets UUU, AAA, GGG, and CCC.
10. Explain in what way the genetic code is redundant and unambiguous.
11. Explain the significance of the reading frame during translation.
12. Explain the evolutionary significance of a nearly universal genetic code.
13. Be able to use the genetic code table to give the amino acid sequence of a nucleotide sequence.
14. Explain how RNA polymerase recognizes where transcription should begin. Describe the promoter, the terminator, and the transcription unit.
15. Explain the general process of transcription, including the three major steps of initiation, elongation, and termination.
16. What substrates are needed for transcription? In what direction is the growing nucleotide assembled?
17. Describe the posttranscriptional modifications and splicing that occur in a eukaryotic cell.
18. Describe the functional and evolutionary significance of introns.
19. Describe or diagram the structure of a tRNA molecule, and explain how its structure relates to its function.
20. Describe or diagram the structure of the ribosome, and explain how its structure relates to its function.
21. Describe the role of aminoacyl-tRNA synthetases in translation.
22. Describe the process of translation (including initiation, elongation, and termination) and explain which enzymes, protein factors, and energy sources are needed for each stage.
23. Describe the significance of polyribosomes.
24. Be able to list the three main types of RNA found in the cell, and give the function of each.
25. Compare and contrast the steps of prokaryotic and eukaryotic transcription.
26. Define "point mutations." Distinguish between base-pair substitutions and base-pair insertions. Give examples of each and note the significance of such changes.
27. Describe the contemporary definition of the concept of a gene.