What eight codons contain only A and C nucleotides? A random mix of A and C nucl
ID: 64439 • Letter: W
Question
What eight codons contain only A and C nucleotides? A random mix of A and C nucleotides used to synthesize an artificial mRNA would be expected to produce those eight codons. The probability of each codon's appearance would be based on the proportions of the two nucleotides in the starting mix. For example if A = .90 and C = .10, an ACA codon would occur with a probability of (0.9)(0.1)(0.9). (This is similar to the probabilities you calculated for genotypes.) So, two scientists trying to decipher the genetic code did an experiment making just such an artificial mRNA from A = .75 and C = .25 and then adding the artificial mRNA to an in vitro translation mixture and determining what amino acids were incorporated into the protein produced. See if you can determine what codons to assign to which amino acids if you have their results:
After in vitro translation they found the following amino acids in the proteins in the proportions indicated:
asparagine (asn) 0.141
threonine (thr) 0.1875
lysine (lys) 0.422
proline (pro) 0.0625
glutamine (gln) 0.141
histidine (his) 0.047
Based on this information, describe the one or more probable codons for each of the 6 amino acids. For each answer, list specific codons alphabetically. If you know a specific codon, then enter it (e.g. ACA). In the case of codons which cannot be distinguished (such as AAC or ACA or CAA), you should enter A2C (if ACC or CAC or CCA enter AC2). So if you know that one unambiguous codon is CCC and the others are either ACC or CAC or CCA, you should enter CCC AC2. List specific codons alphabetically before ambiguous and alternate codons, list A2C before AC2.
14. [1pt]
asn (two tries only)
Answer:
Not yet correct, ONE try left!!
a. [1pt]
thr (two tries only)
Answer:
Not yet correct, ONE try left!!
b. [1pt]
lys (two tries only)
Answer: Last Answer: AAA AAG
Incorrect, ONE try left!!
c. [1pt]
pro (two tries only)
Answer:
d. [1pt]
gln (two tries only)
Answer:
e. [1pt]
his (two tries only)
Answer:
f. [1pt]
Can you assign all the codons unambiguously? (enter yes or no, one try only)
Answer:
If not, can you assign them if you also know that an artificial mRNA made from (A)n(C)n (e.g. AAAAAAAACCCCCCCC) produces proteins with lots of proline and lysine and a little asparagine and threonine, but an artificial mRNA made of (C)n(A)n (e.g. CCCCCCCCAAAAAAAA) produces protein with lots of proline and lysine and a little glutamine?
What are the codon assignments based on these results?
g. [1pt]
asn (one try only)
Answer:
h. [1pt]
thr (one try only)
Answer:
i. [1pt]
lys (one try only)
Answer:
j. [1pt]
pro (one try only)
Answer:
k. [1pt]
gln (one try only)
Answer:
L. [1pt]
his (one try only)
Answer:
**** NOTE: I really need someone to explain how to do it. I'm sure if you do the first couple I can figure the rest out. Obviously I would apprecaite all parts of the answer greatly but im not expecting it
Explanation / Answer
A)
CCA, CCC (proline)
ACC, ACA (threonine)
CAA (glutamine)
AAC (asparagine)
CAC (histidine)
AAA (lysine)
B)
CCC CCC CCA AAA AAA A (case 1)
C CCC CCC CAA AAA AAA (case 2)
Codon for proline (CCC, CCA)
Codon for lysine (AAA)
Codon for glutamine (CAA)
Related Questions
drjack9650@gmail.com
Navigate
Integrity-first tutoring: explanations and feedback only — we do not complete graded work. Learn more.