Question

using the following chart, which chain of amino acids would be produced by the sequence of this very short, complete mrna:
augccugagugaauugcua?
codon chart
○ tyrosine-tyrosine-alanine-stop-valine-asparagine-cysteine
○ methionine-proline-glutamate-isoleucine-alanine
○ tyrosine-tyrosine-alanine
○ methionine-proline-glutamate

Explanation:

Step1: Split mRNA into codons

The mRNA sequence is AUGCCUGAGUGAAUUGCUA. Split into codons (3 - letter units): AUG, CCU, GAG, UGA, AUU, GCU, A (wait, no, correct splitting: AUG, CCU, GAG, UGA, AUU, GCU, A? Wait, no, let's count the length. The mRNA is AUG CCU GAG UGA AUU GCU A? Wait, no, the original mRNA is AUGCCUGAGUGAAUUGCUA. Let's split into 3 - letter codons:

1. AUG (start)
2. CCU
3. GAG
4. UGA (stop codon)
5. AUU (but after stop codon, translation stops)

Wait, let's do it properly:

AUG (1 - 3), CCU (4 - 6), GAG (7 - 9), UGA (10 - 12), AUU (13 - 15), GCU (16 - 18), A (19 - but it's only 1 base, so maybe I made a mistake. Wait the mRNA is AUGCCUGAGUGAAUUGCUA. Let's count the number of nucleotides: A(1), U(2), G(3), C(4), C(5), U(6), G(7), A(8), G(9), U(10), G(11), A(12), A(13), U(14), U(15), G(16), C(17), U(18), A(19)? No, that can't be. Wait the correct way is to split into triplets:

AUG (positions 1 - 3)
CCU (4 - 6)
GAG (7 - 9)
UGA (10 - 12)
AUU (13 - 15)
GCU (16 - 18)
A (19 - invalid, so maybe the mRNA is AUGCCUGAGUGAAUUGCUA (18 nucleotides? Let's check: AUG (3) + CCU (3) + GAG (3) + UGA (3) + AUU (3) + GCU (3) = 18. Oh, I miscounted. So the codons are:

1. AUG
2. CCU
3. GAG
4. UGA
5. AUU
6. GCU

But UGA is a stop codon, so translation stops at UGA. So we only consider codons before UGA? Wait no, let's check the codon table:

• AUG: Methionine (start)
• CCU: Proline (first letter C, second C, third U: look at first letter C, second C, third U: CCU is Proline)
• GAG: Glutamate (first letter G, second A, third G: GAG is Glutamate)
• UGA: Stop codon (so translation stops here)

Wait, but the options are:

Option 1: tyrosine - tyrosine - alanine - stop - valine - asparagine - cysteine

Option 2: methionine - proline - glutamate - isoleucine - alanine

Option 3: tyrosine - tyrosine - alanine

Option 4: methionine - proline - glutamate

Wait, let's re - evaluate the codons:

mRNA: AUG CCU GAG UGA AUU GCU A? No, let's take the mRNA as AUGCCUGAGUGAAUUGCUA (18 nucleotides: AUG (3), CCU (3), GAG (3), UGA (3), AUU (3), GCU (3)).

Codon 1: AUG → Methionine

Codon 2: CCU → Proline (first letter C, second C, third U: in the table, first letter C, second C, third U: CCU is Proline)

Codon 3: GAG → Glutamate (first letter G, second A, third G: GAG is Glutamate)

Codon 4: UGA → Stop codon (so translation stops here, so the amino acid chain is Methionine - Proline - Glutamate)

Let's check the options:

Option 4: methionine - proline - glutamate → matches.

Let's verify each codon:

• AUG: Methionine (start codon, correct)
• CCU: Proline (first letter C, second C, third U: in the table, row C (first letter), column C (second letter), third letter U: CCU is Proline, correct)
• GAG: Glutamate (first letter G, second letter A, third letter G: row G, column A, third letter G: GAG is Glutamate, correct)
• UGA: Stop codon, so translation stops. So the chain is Methionine - Proline - Glutamate.

Answer:

methionine - proline - glutamate (the option corresponding to this, which is the fourth option: methionine - proline - glutamate)