Transcription and Translation 18 a Label the | StudyX - Free Printable

Let’s go step by step to label the diagram correctly.

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Part (a): Labeling the Diagram

We’ll match each numbered part in the diagram with the correct term from the word list.

#### Top Half – Transcription (happens in nucleus)

1. This is the RNA strand being made → It’s called mRNA (transcription) because it’s being synthesized during transcription.
2. These are individual building blocks of RNA → They’re called nucleotides.
3. This enzyme is making the mRNA → That’s RNA polymerase.
4. The big structure holding everything together in the top half → This is the nucleus.
5. The DNA strand that’s being copied → This is the DNA - template strand.

Also, note: The other DNA strand (not being copied) is the DNA - coding strand, but it’s not labeled with a number here — so we don’t need to assign it unless asked.

→ So for A (top box), since this whole process is happening inside the nucleus and involves making mRNA from DNA, the best label is:
A = nucleus

Wait — actually, looking again: Box A is pointing to the entire top section where transcription happens. But in many diagrams, they label the *location*. Since transcription occurs in the nucleus, and the diagram shows DNA unwound inside a membrane-bound area, A should be “nucleus”.

But let’s check the bottom half too.

#### Bottom Half – Translation (happens in cytoplasm)

6. Big machine reading mRNA and assembling protein → That’s the ribosome.
7. The long strand with codons being read → This is mRNA (translation) — same molecule as above, now being used for translation.
8. tRNA without an amino acid attached → Look at the tRNA on the left — it has no circle (amino acid) at the bottom → tRNA without amino acid
9. Chain of amino acids forming a protein → That’s the peptide chain.
10. Individual units making up the peptide → These are amino acids.
11. Three-letter code on mRNA → That’s a codon.
12. Three-letter code on tRNA that matches codon → That’s the anticodon.
13. tRNA carrying an amino acid → The one on the right has “Glu” attached → tRNA with amino acid

Now, boxes B, C, D:

- B points to the space between nucleus and ribosome → that’s the cytoplasm (where translation happens).
- C points to the bottom section where translation occurs → also cytoplasm? Wait — actually, C is labeling the location of translation. In eukaryotes, translation happens in the cytoplasm. So C = cytoplasm
- D is the vertical arrow showing direction of translation → but the question says “label using word list”, and D is likely indicating the process itself → translation

Wait — let’s recheck the instructions: “Label the diagram below, using the following word list”

Looking at the red numbers 1–13, those are what we need to label first. Then boxes A, B, C, D are probably locations or processes.

Actually, looking at standard biology diagrams:

- A is likely labeling the nucleus (since transcription happens there)
- B is the nuclear membrane (the barrier between nucleus and cytoplasm)
- C is the cytoplasm (where translation happens)
- D is the process of translation

Yes, that makes sense.

So let’s compile all labels:

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Numbered Labels (1 to 13):

1. mRNA (transcription) — newly made RNA strand
2. nucleotide — individual units added to make RNA
3. RNA polymerase — enzyme synthesizing RNA
4. nucleus — organelle where transcription occurs
5. DNA - template strand — the strand being transcribed
6. ribosome — site of protein synthesis
7. mRNA (translation) — same mRNA now being translated
8. tRNA without amino acid — empty tRNA after dropping off amino acid
9. peptide — growing chain of amino acids
10. amino acid — monomers making up peptide
11. codon — triplet on mRNA
12. anticodon — complementary triplet on tRNA
13. tRNA with amino acid — tRNA carrying its cargo

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Box Labels (A, B, C, D):

A. nucleus — where transcription occurs
B. nuclear membrane — separates nucleus from cytoplasm
C. cytoplasm — where translation occurs
D. translation — the process shown in bottom half

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Part (b): Label 5’ and 3’ ends

In nucleic acids:

- New strands are always built 5’ → 3’
- During transcription, RNA polymerase reads DNA template 3’ → 5’, and builds mRNA 5’ → 3’

In the top diagram:

- The mRNA strand already has “5’” labeled at the left end → so the right end must be 3’
- For DNA strands:
- Template strand (being read) runs 3’ → 5’ (so if mRNA is 5’→3’, template must be antiparallel: 3’→5’)
- Coding strand runs same direction as mRNA: 5’→3’

So:

Top DNA double helix:

- Upper strand (coding strand): left end = 5’, right end = 3’
- Lower strand (template strand): left end = 3’, right end = 5’

mRNA: left = 5’, right = 3’ (already marked 5’ on left, so mark 3’ on right)

Bottom diagram (translation):

mRNA strand: since ribosome moves 5’ → 3’, and we see start codon AUG on left, then the left end is 5’, right end is 3’

tRNAs: their anticodons bind antiparallel to codons, but we don’t usually label 5’/3’ on tRNA in basic diagrams — only on mRNA and DNA.

So for part (b), we label:

Top diagram:

- mRNA: left = 5’ (given), right = 3’
- DNA coding strand (top strand of helix): left = 5’, right = 3’
- DNA template strand (bottom strand of helix): left = 3’, right = 5’

Bottom diagram:

- mRNA: left = 5’, right = 3’

(No need to label tRNA ends unless specified — and the question says “all DNA and RNA strands”, so just mRNA and DNA.)

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## Final Answer:

(a) Labels:

1. mRNA (transcription)
2. nucleotide
3. RNA polymerase
4. nucleus
5. DNA - template strand
6. ribosome
7. mRNA (translation)
8. tRNA without amino acid
9. peptide
10. amino acid
11. codon
12. anticodon
13. tRNA with amino acid

A. nucleus
B. nuclear membrane
C. cytoplasm
D. translation

(b) 5’ and 3’ ends:

Top Diagram:

- mRNA: left end = 5’ (already labeled), right end = 3’
- DNA coding strand (upper strand): left = 5’, right = 3’
- DNA template strand (lower strand): left = 3’, right = 5’

Bottom Diagram:

- mRNA: left end = 5’, right end = 3’

*(Note: In the bottom diagram, the mRNA strand runs left to right, with start codon AUG on the left, so 5’ is left, 3’ is right.)*