Download Worksheet - Oregon State University

BI314 Name __________________________________ Recitation 3 Date __________________________________ 1. How would the following types of DNA mutations change the protein product? A. Insertion of a single nucleotide near the end of the coding sequence B. Removal of a single nucleotide near the beginning of the coding sequence C. Deletion of three consecutive nucleotides in the middle of the coding sequence D. Deletion of four consecutive nucleotides in the middle of the coding sequence E. Substitution of one nucleotide for another in the middle of the coding sequence 2. The ribosome is made up of (select all that apply): a. a large and small subunit b. 80+ proteins c. tRNA d. rRNA 3. What allows a ribosome to correctly recognize the site to start translation in prokaryotes? In eukaryotes? 4. tRNAs contain a hairpin loop with sequence that interacts with mRNA a. What is the function of an anticodon? b. What catalyzes the linkage of the appropriate amino acid to its conjugate tRNA? c. What kind of bond is catalyzed? d. What is the initiator tRNA? 5. Draw a dipeptide. Circle the polypeptide bond. 6. What molecule ends polypeptide synthesis by recognizing the stop codon? Learning Goals Below is what you should know for understanding material in lecture: -1Be able to identify:
-A base; identify whether purine or pyrimidine. Recognize the similarity of A to G and T to C/U
-Ribose and deoxyribose, and mark the difference between them.
-A nucleoside
-A nucleotide
-The 5’ and 3’ ends of a nucleotide or nucleic acid, and what this means (for function,
complimentarity, etc.)
-A phosphodiester bond
-Hydrogen bonds between bases (what they are, how many?)
-The antiparallel nature of double-stranded DNA
Be able to:
-Correctly number the carbons on a ribose or deoxyribose sugar
-Tell from a figure whether the nucleic acid shown is RNA or DNA
-Show how a DNA or RNA molecule is assembled (what is the direction of growth of the new
strand, where does the new nucleotide attaché, what precursors are used)
-Explain the relationship between nucleotides, genes and chromosomes.
-2Be able to explain:
What is a gene?
What is transcription?
What is a coding region?
What is the relationship between a gene and the RNA transcribed from it?
What are the 5’ and 3’ UTRs?
What are stop and start codons?
What is the difference between transcriptional start and termination sites and start and stop
codons?
Make sure these things are clear:
That not all RNAs encode proteins
That protein coding RNAs don't start at the start codon and end at the stop codon
That only one strand of the DNA template is copied.
-3Know what a Ribosome Binding Site (Shine-Dalgarno sequence) is, where it is located.
Be able to say what a ribosome is, what it is made of
Know the function of tRNAs
Know what an initiator tRNA is.
Know what a codon and an anticodon are.
Know the signals for the start and termination of protein synthesis (the start codon sequence and
the 3 stop codons), where they are with respect to the RBS, and the transcriptional start and
termination sites.
What kind of bond links amino acids (the name of the bond, how it's formed, what it looks like)
What happens to the ribosome and mRNA after protein synthesis is completed