Let’s go step by step to solve this transcription and translation worksheet.
We are given DNA sequences (template strand) and need to:
1. Transcribe them into mRNA (remember: A→U, T→A, C→G, G→C)
2. Translate the mRNA into amino acids using the codon table
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Problem 1:
DNA: TAC TGA TGC ACC CCC ATA ATG AAA ATC
mRNA: AUG ACU ACG UGG GGG UAU UAC UUU UAG
(Transcription: replace T with U, and pair bases correctly)
Now translate each codon:
- AUG → Met (start)
- ACU → Thr
- ACG → Thr
- UGG → Trp
- GGG → Gly
- UAU → Tyr
- UAC → Tyr
- UUU → Phe
- UAG → STOP
So protein:
Met-Thr-Thr-Trp-Gly-Tyr-Tyr-Phe-STOP
But wait — let’s check the student’s answer in the image: they wrote “MET - THR - THR - TRP - GLY - TYR - TYR - PHE - STOP” — that matches!
✔ Correct for #1.
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Problem 2:
DNA: TAC CCA CGC CCT AGT GCT GAA ATT ACT
mRNA: AUG GGU GCG GGA UCA CGA CUU UAA UGA
Wait — let’s transcribe carefully:
DNA: T A C C C A C G C C C T A G T G C T G A A A T T A C T
mRNA: A U G G G U G C G G G A U C A C G A C U U U A A U G A
Now translate:
- AUG → Met
- GGU → Gly
- GCG → Ala
- GGA → Gly
- UCA → Ser
- CGA → Arg
- CUU → Leu
- UAA → STOP
- UGA → STOP (but we stop at first stop codon)
So protein:
Met-Gly-Ala-Gly-Ser-Arg-Leu-STOP
Student wrote: “MET - GLY - ALA - GLY - SER - ARG - LEU - STOP” — correct!
✔ Correct for #2.
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Problem 3:
DNA: TAC GCC CGC CCT AGT GCT GAA ATT ACT
Wait — this looks identical to problem 2? Let me check...
Actually, looking again — in the image, problem 3 is:
DNA: TAC GCC CGC CCT AGT GCT GAA ATT ACT
mRNA: AUG CGG GCG GGA UCA CGA CUU UAA UGA
Translate:
- AUG → Met
- CGG → Arg
- GCG → Ala
- GGA → Gly
- UCA → Ser
- CGA → Arg
- CUU → Leu
- UAA → STOP
Protein:
Met-Arg-Ala-Gly-Ser-Arg-Leu-STOP
Student wrote: “MET - ARG - ALA - GLY - SER - ARG - LEU - STOP” — correct!
✔ Correct for #3.
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Problem 4:
DNA: TAC GCA GCA CAT TAT CAG CAT CAT
mRNA: AUG CGU CGU GUA AUA GUC GUA GUA
Translate:
- AUG → Met
- CGU → Arg
- CGU → Arg
- GUA → Val
- AUA → Ile
- GUC → Val
- GUA → Val
- GUA → Val
No stop codon? But the sequence ends — maybe it’s incomplete? Or perhaps we assume it stops at end?
Student wrote: “MET - ARG - ARG - VAL - ILE - VAL - VAL - VAL”
That’s fine if no stop codon is present — just list all amino acids.
✔ Correct for #4.
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Problem 5:
DNA: CTC ACA GTA GGC ... TTG CGA ATT
Wait — this one has ellipsis (...) meaning part is missing? But student filled in:
mRNA: GAG UGU CAU CCG ... AAC GCU UAA
Then translated: Glu-Cys-His-Pro...-Asn-Ala-STOP
Let’s verify:
DNA: CTC → mRNA: GAG → Glu
ACA → UGU → Cys
GTA → CAU → His
GGC → CCG → Pro
... (missing part)
TTG → AAC → Asn
CGA → GCU → Ala
ATT → UAA → STOP
Yes — so even though middle is missing, the ends are correct.
Student wrote: “GLU - CYS - HIS - PRO - ... - ASN - ALA - STOP” — acceptable.
✔ Correct for #5.
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All answers match what should be expected based on standard genetic code.
Final Answer: All problems solved correctly as shown in the worksheet.
Parent Tip: Review the logic above to help your child master the concept of translation worksheet answers.
