transcription worksheet Doc Template | pdfFiller - Free Printable

Let’s go step by step through each question on the worksheet. We’ll start with Part 1: DNA, then move to Part 2: RNA.

---

Part 1 – DNA

1. What does DNA stand for, and what role is DNA found in the cell?
DNA stands for Deoxyribonucleic Acid. It’s found in the nucleus of the cell (in eukaryotes like humans). Its main job is to store genetic instructions — like a blueprint — that tell the cell how to build proteins and run all its functions.

✔ Final Answer for #1:
Deoxyribonucleic Acid; nucleus

---

2. Why is it important for DNA to make exact copies of itself?
When a cell divides, each new cell needs to have the same genetic information as the original. If DNA didn’t copy exactly, mistakes could happen — which might cause diseases or problems in growth and development. Exact copying ensures every cell works correctly.

✔ Final Answer for #2:
So each new cell gets the correct genetic instructions to function properly.

---

3. When does DNA replication occur?
DNA replication happens during the S phase (Synthesis phase) of the cell cycle — right before the cell divides (mitosis or meiosis). This way, when the cell splits, both daughter cells get a full set of DNA.

✔ Final Answer for #3:
During the S phase of the cell cycle, before cell division.

---

4. Place the diagrams in the correct order by writing the numbers 1 through 3 above each diagram. Then answer the questions that follow.

We’re given three diagrams showing steps of DNA replication:

- Left diagram: Shows two strands separating, with “Complementary bases attach to template” → this is step 2 (bases are being added).
- Middle diagram: Shows two complete double helices labeled “Two molecules of DNA identical to each other and the original molecule are made” → this is step 3 (final result).
- Right diagram: Shows one double helix unzipping, labeled “DNA ‘unzips’” → this is step 1 (starting point).

So the correct order is:
→ Right diagram = 1
→ Left diagram = 2
→ Middle diagram = 3

✔ Final Answer for #4:
Right: 1, Left: 2, Middle: 3

---

5. What process is shown in these diagrams?
The diagrams show DNA making a copy of itself — that’s called DNA replication.

✔ Final Answer for #5:
DNA replication

---

6. How are enzymes involved in this process?
Enzymes help speed up and control DNA replication. For example:
- Helicase unzips the DNA.
- DNA polymerase adds new nucleotides to build the new strand.
- Ligase glues pieces together if needed.

Without enzymes, DNA couldn’t replicate quickly or accurately.

✔ Final Answer for #6:
Enzymes like helicase unzip DNA, and DNA polymerase builds new strands — they make replication fast and accurate.

---

7. What happens after the DNA “unzips”?
After DNA unzips, each separated strand acts as a template. Free-floating nucleotides in the cell match up with their complementary bases (A with T, C with G), and enzymes link them together to form two new double-stranded DNA molecules.

✔ Final Answer for #7:
Each strand serves as a template for building a new complementary strand, forming two identical DNA molecules.

---

8. Suppose that a sequence of one DNA strand is TACAACGTG. What is the corresponding sequence on the other strand?

Remember base pairing rules:
- A pairs with T
- T pairs with A
- C pairs with G
- G pairs with C

So let’s pair each letter:

Original: T A C A A C G T G
Complement: A T G T T G C A C

✔ Final Answer for #8:
ATGTTGCAC

---

Part 2 – RNA

1. What does RNA stand for?
RNA stands for Ribonucleic Acid.

✔ Final Answer for #1:
Ribonucleic Acid

---

2. Describe the structure of RNA.
RNA is usually a single strand (not double like DNA). It has a sugar called ribose (instead of deoxyribose in DNA), and uses uracil (U) instead of thymine (T). So base pairing in RNA is: A-U, C-G.

✔ Final Answer for #2:
Single-stranded, contains ribose sugar, and uses uracil (U) instead of thymine (T).

---

3. How does RNA differ from DNA? (3 ways)
Here are 3 key differences:

1. Structure: DNA is double-stranded; RNA is usually single-stranded.
2. Sugar: DNA has deoxyribose; RNA has ribose.
3. Bases: DNA uses thymine (T); RNA uses uracil (U) instead.

✔ Final Answer for #3:
**1. RNA is single-stranded; DNA is double-stranded.
2. RNA has ribose sugar; DNA has deoxyribose.
3. RNA uses uracil (U); DNA uses thymine (T).**

---

4. List the three types of RNA and give the function of each.

There are 3 main types:

a. mRNA (messenger RNA) – carries the genetic code from DNA in the nucleus to the ribosome in the cytoplasm.

b. tRNA (transfer RNA) – brings amino acids to the ribosome during protein synthesis. Each tRNA matches a specific codon on mRNA.

c. rRNA (ribosomal RNA) – makes up part of the ribosome, where proteins are built.

✔ Final Answer for #4:
**a. mRNA – carries genetic message from DNA to ribosome
b. tRNA – brings amino acids to ribosome
c. rRNA – part of ribosome structure, helps build proteins**

---

## ✔ FINAL ANSWERS (ALL TOGETHER):

Part 1 – DNA

1. Deoxyribonucleic Acid; nucleus
2. So each new cell gets the correct genetic instructions to function properly.
3. During the S phase of the cell cycle, before cell division.
4. Right: 1, Left: 2, Middle: 3
5. DNA replication
6. Enzymes like helicase unzip DNA, and DNA polymerase builds new strands — they make replication fast and accurate.
7. Each strand serves as a template for building a new complementary strand, forming two identical DNA molecules.
8. ATGTTGCAC

Part 2 – RNA

1. Ribonucleic Acid
2. Single-stranded, contains ribose sugar, and uses uracil (U) instead of thymine (T).
3.
- RNA is single-stranded; DNA is double-stranded.
- RNA has ribose sugar; DNA has deoxyribose.
- RNA uses uracil (U); DNA uses thymine (T).
4.
a. mRNA – carries genetic message from DNA to ribosome
b. tRNA – brings amino acids to ribosome
c. rRNA – part of ribosome structure, helps build proteins