Question

amino acid codon chart
fruit fly dna sequence
...tgg-aac-caa...
a scientist examines a fruit fly gene involved in the regulation of body development. a section of the dna sequence for the gene is shown in the diagram above.
which rna sequence was used to create the amino acid sequence you selected in the previous question?

• acc-ttc-gtt
• caa-ggt-tgg
• ucc-ttc-gtt
• acc-uug-guu

Explanation:

Step1: Recall DNA to RNA Transcription

In transcription, DNA's thymine (T) is replaced by RNA's uracil (U), and adenine (A) pairs with uracil (U), cytosine (C) pairs with guanine (G), guanine (G) pairs with cytosine (C), and thymine (T) pairs with adenine (A) in DNA - RNA base pairing. Wait, no: DNA to RNA: A→U, T→A, C→G, G→C. Wait, the DNA sequence given is... Wait, the original DNA sequence (from the fruit fly) is... Wait, the question is about the RNA sequence from the DNA. Wait, the options: Let's check the DNA - RNA conversion. Wait, the DNA sequence (assuming the original DNA is... Wait, the first option is ACC - TTC - GTT. Wait, no, let's think about complementary base pairing. Wait, DNA has A, T, C, G; RNA has A, U, C, G. So to get RNA from DNA, replace T with U? No, wait, transcription: DNA template strand to RNA. Wait, maybe the original DNA is... Wait, the fruit fly DNA sequence is... Wait, the problem's DNA sequence (from the diagram) is _IGG - AAC - CAA_ (maybe a typo, like TGG - AAC - CAA? Wait, no, the options: Let's check each option. Wait, the correct RNA sequence should be complementary to the DNA template. Wait, maybe the original DNA is TGG - AAC - CAA? Then RNA would be ACC - UUG - GUU? No, wait the options have ACC - UUG - GUU? Wait, no, the options: the last option is ACC - UUG - GUU? Wait, no, the last option is ACC - UUG - GUU? Wait, the options are:

1. ACC - TTC - GTT (has T, so DNA, not RNA)
2. CAA - GGT - TGG (has T, DNA)
3. UCC - TTC - GTT (has U, but let's check base pairing)
4. ACC - UUG - GUU (has U, so RNA)

Wait, no, maybe I messed up. Wait, the key is that RNA has U instead of T. So any option with T is DNA, so options 1,2 have T, so they are DNA. Option 3 has U but let's check base pairing. Wait, no, let's re - examine. Wait, the question is "Which RNA sequence was used to create the amino acid sequence...", so RNA must have U (since RNA uses U, not T). So options 1 (ACC - TTC - GTT) has T, so DNA. Option 2 (CAA - GGT - TGG) has T, DNA. Option 3 (UCC - TTC - GTT) has T? No, UCC - TTC - GTT: T is present, so that's a mix? No, RNA has U, not T. Wait, option 4: ACC - UUG - GUU: has U, no T. So that's RNA. Wait, but let's check the base pairing. Wait, maybe the original DNA is TGG - AAC - CAA. Then RNA (transcribed from DNA) would be ACC - UUG - GUU (since T→A, G→C, G→C, A→U, A→U, C→G, C→G, A→U, A→U? Wait, no, DNA to RNA: each DNA base is transcribed to RNA: A→U, T→A, C→G, G→C. So if DNA is TGG - AAC - CAA, then RNA would be ACC - UUG - GUU (T→A, G→C, G→C; A→U, A→U, C→G; C→G, A→U, A→U). Yes, that matches option 4: ACC - UUG - GUU. Wait, but in the options, the last one is ACC - UUG - GUU? Wait, the user's options: the last option is "ACC - UUG - GUU"? Wait, the user's image shows the last option as "ACC - UUG - GUU"? Wait, the user's text: "ACC - UUG - GUU" is the last option? Wait, the user's options:

- ACC - TTC - GTT

- CAA - GGT - TGG

- UCC - TTC - GTT

- ACC - UUG - GUU

So the correct RNA sequence must have U (since RNA has U, not T) and be complementary to the DNA. So options 1 and 2 have T, so they are DNA. Option 3 has U but also T (TTC), which is wrong (RNA has no T). Option 4 has U (UUG, GUU) and no T, so it's RNA. Also, base pairing: if DNA is TGG - AAC - CAA, then RNA is ACC - UUG - GUU (T→A, G→C, G→C; A→U, A→U, C→G; C→G, A→U, A→U). So the correct option is the last one: ACC - UUG - GUU. Wait, but in the user's options, the last one is "ACC - UUG - GUU"? Wait, the user's last option is "ACC - UUG - GUU"? Yes. So the correct answer is the last option.

Step2: Eliminate DNA - containing Options

Options with T (thymine) are DNA, so options 1 (ACC - TTC - GTT) and 2 (CAA - GGT - TGG) have T, so they are DNA, not RNA. Option 3 (UCC - TTC - GTT) has T (in TTC), so it's invalid (RNA has U, not T). Option 4 (ACC - UUG - GUU) has U (no T) and follows base - pairing rules for DNA - to - RNA transcription.

Answer:

ACC - UUG - GUU (the last option, assuming the options are labeled as: 4. ACC - UUG - GUU) Wait, but in the user's options, the last one is "ACC - UUG - GUU"? So the answer is the option with "ACC - UUG - GUU".