DNA Coloring (KEY) by Biologycorner | TPT - Free Printable

Let’s go through this step by step.

We’re looking at a coloring activity about DNA and RNA. The worksheet has two parts: Part 1 is about DNA structure, and Part 2 is about Messenger RNA (mRNA). We’ll focus on Part 1 first since that’s where the main labeling and coloring instructions are.

In Part 1, we’re told to color different parts of the DNA molecule based on what they are:

- Phosphate = orange
- Deoxyribose sugar = green
- Adenine (A) = red
- Thymine (T) = blue
- Guanine (G) = yellow
- Cytosine (C) = purple

Then we’re shown a diagram with boxes labeled “phosphate,” “deoxyribose sugar,” and bases like “adenine,” “thymine,” etc., connected in pairs.

The key thing to remember about DNA structure:
- DNA is made of two strands twisted into a double helix (like a spiral ladder).
- Each strand is made of repeating units called nucleotides.
- Each nucleotide has three parts: a phosphate group, a sugar (deoxyribose), and one nitrogen base (A, T, G, or C).
- The bases pair up across the two strands: A always pairs with T, and G always pairs with C. This is called complementary base pairing.

Looking at the diagram in the worksheet:

There are two columns of boxes — left side and right side — representing the two strands of DNA.

On the left side, from top to bottom, we have:
- phosphate → should be colored orange
- deoxyribose sugar → green
- adenine → red
Then below that:
- phosphate → orange
- deoxyribose sugar → green
- thymine → blue

On the right side, it shows:
- phosphate → orange
- deoxyribose sugar → green
- thymine → blue (because it pairs with adenine on the left)
Then below that:
- phosphate → orange
- deoxyribose sugar → green
- adenine → red (because it pairs with thymine on the left)

Wait — let’s check the actual diagram description again.

Actually, looking more carefully at the text under “Part 1: DNA Structure”:

It says:

> Color each part of the DNA molecule according to the key below:
> - Phosphate = orange
> - Deoxyribose sugar = green
> - Adenine = red
> - Thymine = blue
> - Guanine = yellow
> - Cytosine = purple

Then there’s a diagram with two vertical chains. Each chain has alternating phosphate and sugar, with bases sticking out toward the middle.

The left chain has:
Top: phosphate – sugar – adenine
Bottom: phosphate – sugar – thymine

The right chain has:
Top: phosphate – sugar – thymine
Bottom: phosphate – sugar – adenine

That makes sense because A pairs with T.

So for coloring:

Left chain:
- Top phosphate → orange
- Top sugar → green
- Top base (adenine) → red
- Bottom phosphate → orange
- Bottom sugar → green
- Bottom base (thymine) → blue

Right chain:
- Top phosphate → orange
- Top sugar → green
- Top base (thymine) → blue
- Bottom phosphate → orange
- Bottom sugar → green
- Bottom base (adenine) → red

Also, note that the hydrogen bonds between A-T are shown as dotted lines — those don’t get colored, just the molecules themselves.

Now, moving to Part 2: Messenger RNA.

This part explains how mRNA is made from DNA during transcription.

Key points:
- mRNA is single-stranded.
- It uses ribose sugar instead of deoxyribose.
- Instead of thymine (T), it uses uracil (U).
- Base pairing rules for mRNA: A pairs with U, G pairs with C.

The worksheet gives an example:

DNA template strand: TAC GGC TTA
mRNA strand: AUG CCG AAU

Let’s verify that:

DNA: T → mRNA: A
DNA: A → mRNA: U
DNA: C → mRNA: G
So TAC → AUG ✔️

DNA: G → mRNA: C
DNA: G → mRNA: C
DNA: C → mRNA: G
So GGC → CCG ✔️

DNA: T → mRNA: A
DNA: T → mRNA: A
DNA: A → mRNA: U
So TTA → AAU ✔️

Perfect.

Now, the question asks us to complete the mRNA sequence for the given DNA template strand:

DNA: ATG CCC GAT

Let’s do it step by step:

First base: A → in mRNA, A pairs with U → so first base of mRNA is U

Second base: T → in mRNA, T pairs with A → so second base is A

Third base: G → in mRNA, G pairs with C → so third base is C

So first codon: ATG → UAC

Fourth base: C → mRNA: G
Fifth base: C → mRNA: G
Sixth base: C → mRNA: G
So CCC → GGG

Seventh base: G → mRNA: C
Eighth base: A → mRNA: U
Ninth base: T → mRNA: A
So GAT → CUA

Putting it all together:

DNA: ATG CCC GAT
mRNA: UAC GGG CUA

Let me double-check:

ATG → A→U, T→A, G→C → UAC ✔️
CCC → C→G, C→G, C→G → GGG ✔️
GAT → G→C, A→U, T→A → CUA ✔️

Yes, that’s correct.

Final Answer:
UAC GGG CUA