Wondering if someone can check this (DNA related)

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Wondering if someone can check this (DNA related)

Post by mjaigirdar » Sun Feb 08, 2009 11:15 pm

1, Name the monomer of which DNA is made: Nucleotide
2. In which part of the DNA monomer will the heavy isotope 15N from e. coli be found: The base
2b. Given that 15% of the bases in a piece of DNA are thymine, calculate the percentage of the bases that are guanine: 35%

ATG: Tyrosine
TAC: Methionine
CCT: Glycine
TCG: Serine
CGT: Alanine
1. Write down the amino acid sequence coded for by a piece of messenger RNA with the following base sequence (AUG AGC GCA GCA UAC GGA): Methionine, Serine, Alanine, Alanine, Tyrosine, Glycine

A gene mtation resulted in the final mRNA codon changing from GGA to GCA. What kind of mutation is this: Altered Base Pair (Singe base pair mutation)

Name the amino acid coded for by the mutated gene: Alanine

Explain how all the possible condons (64) are used in protein syntehsis even though there are only 20 different amino acids: The extra codes ar eused as start and stop codons. There are also repititions of each amino acid because it can use 3/4/5 codons

3) Name the amino acid which would be carred by this tRNA molecule (Anticodon: UAC; Amino Acid: ACC): Methionine

1) What chemical bond links the part of the molecule between 2 amino acids: A hydrogen bond

Out of DNA/mRNA/tRNA, what...
1) may contain the base uracil: mRNA, tRNA
2) Contains groups linked by hydrogen bonds: DNA, mRNA, tRNA
3) Contains a 5-carbon sugar: DNA, mRNA, tRNA
4) Involved in transcription: mRNA

Given: Strand AAC circled (from DNA)
a. Give the b ase sequence of the mRNA molecule that would be transcribed from thsi strand: UUG
b. Give the base sequence of the tRNA anticodon corresponding to the base sequence shown in the box: GUU
c. A gene mutation is a change involving the DNA base sequence. Suggest an explanation for the fact that substituting one base for another may have no effect on the protein coded for by this length of DNA: When a 2nd mutation is applied that cancels out the first mutation, it seems as if no effect happened in the organism. Codons are degenerate but changing an amino acid will affect the organism
d. Suggest an explanation for the fact that the addition of an extra base in teh sequence may produce an entirely different protein: Adding a single extra base would keep the DNA from being read 3 letters at a time. Everything afterwards is meaningless

4) Use the table to give a tRNA anticodon for the amino acid Tyr. (UAU and UAC are Tyr): AUG

Use the information in the table to explain what is meant by the following features of the genetic code. It is...
A triple code: A group fo 3 bases is used in order to determine the amino acid
A universal code: The code stays constant and is the same for all humans

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Post by mith » Mon Feb 09, 2009 6:56 pm

1) What chemical bond links the part of the molecule between 2 amino acids: A hydrogen bond

No, peptide bond.
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