Biology worksheet on nucleic acids and DNA structure.
Student worksheet for biology focusing on nucleic acids, with fill-in-the-blank questions about DNA structure, nucleotides, and base pairing.
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Step-by-step solution for: Nucleic acids summary worksheet
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Step-by-step solution for: Nucleic acids summary worksheet
Here is the completed Student Worksheet—Biology with correct answers and explanations for each question:
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Strand: Molecules and Cells
Tutorial: Nucleic Acids
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1. Two types of nucleic acid are ________ and ________.
✔ Answer: *DNA* and *RNA*
Explanation: The two main types of nucleic acids are deoxyribonucleic acid (DNA) and ribonucleic acid (RNA). DNA stores genetic information, while RNA helps in protein synthesis.
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2. The ladder-like structure of DNA is known as a ________.
✔ Answer: *Double helix*
Explanation: The DNA molecule has a twisted ladder shape called the double helix, consisting of two strands coiled around each other.
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3. The sides of the DNA ladder are composed of ________.
✔ Answer: *Sugar and phosphate groups*
Explanation: The backbone (sides) of the DNA ladder is made up of alternating sugar (deoxyribose) and phosphate molecules, forming a sugar-phosphate backbone.
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4. The rungs of the DNA ladder are made of ________.
✔ Answer: *Nitrogenous bases*
Explanation: The rungs are formed by pairs of nitrogenous bases that connect the two strands of DNA through hydrogen bonds.
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5. The nucleic acids are polymers of ________.
✔ Answer: *Nucleotides*
Explanation: Nucleic acids like DNA and RNA are long chains (polymers) made of repeating units called nucleotides.
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6. The three components of a nucleotide are ________, ________, and ________.
✔ Answer: *Phosphate group*, *sugar*, and *nitrogenous base*
Explanation: Each nucleotide consists of:
- A phosphate group,
- A five-carbon sugar (deoxyribose in DNA, ribose in RNA),
- And a nitrogen-containing base (adenine, thymine, cytosine, guanine in DNA).
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7. The sugar in DNA is ________.
✔ Answer: *Deoxyribose*
Explanation: DNA contains deoxyribose sugar, which lacks one oxygen atom compared to ribose (found in RNA).
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8. The four bases in DNA are ________, ________, ________, and ________.
✔ Answer: *Adenine*, *Thymine*, *Cytosine*, and *Guanine*
Explanation: These are the four nitrogenous bases found in DNA. Adenine and Guanine are purines; Thymine and Cytosine are pyrimidines.
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9. In RNA thymine is replaced by ________.
✔ Answer: *Uracil*
Explanation: RNA uses uracil instead of thymine. Uracil pairs with adenine in RNA, just like thymine does in DNA.
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10. What holds the two nucleotide strands together in DNA?
✔ Answer: *Hydrogen bonds between nitrogenous bases*
Explanation: Hydrogen bonds form between complementary nitrogenous bases on opposite strands. These weak bonds allow the strands to separate during processes like replication.
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11. How do the bases pair in DNA?
✔ Answer:
Adenine always pairs with Thymine
And
Cytosine always pairs with Guanine
Explanation: This is known as complementary base pairing.
- A (adenine) pairs with T (thymine) via two hydrogen bonds.
- C (cytosine) pairs with G (guanine) via three hydrogen bonds.
This specific pairing ensures accurate copying of genetic information.
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| Question | Answer |
|--------|--------|
| 1 | DNA and RNA |
| 2 | Double helix |
| 3 | Sugar and phosphate groups |
| 4 | Nitrogenous bases |
| 5 | Nucleotides |
| 6 | Phosphate group, sugar, nitrogenous base |
| 7 | Deoxyribose |
| 8 | Adenine, Thymine, Cytosine, Guanine |
| 9 | Uracil |
| 10 | Hydrogen bonds between nitrogenous bases |
| 11 | Adenine → Thymine; Cytosine → Guanine |
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Let me know if you'd like this worksheet formatted for printing or need a version with blanks filled in!
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Student Worksheet—Biology
Strand: Molecules and Cells
Tutorial: Nucleic Acids
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1. Two types of nucleic acid are ________ and ________.
✔ Answer: *DNA* and *RNA*
Explanation: The two main types of nucleic acids are deoxyribonucleic acid (DNA) and ribonucleic acid (RNA). DNA stores genetic information, while RNA helps in protein synthesis.
---
2. The ladder-like structure of DNA is known as a ________.
✔ Answer: *Double helix*
Explanation: The DNA molecule has a twisted ladder shape called the double helix, consisting of two strands coiled around each other.
---
3. The sides of the DNA ladder are composed of ________.
✔ Answer: *Sugar and phosphate groups*
Explanation: The backbone (sides) of the DNA ladder is made up of alternating sugar (deoxyribose) and phosphate molecules, forming a sugar-phosphate backbone.
---
4. The rungs of the DNA ladder are made of ________.
✔ Answer: *Nitrogenous bases*
Explanation: The rungs are formed by pairs of nitrogenous bases that connect the two strands of DNA through hydrogen bonds.
---
5. The nucleic acids are polymers of ________.
✔ Answer: *Nucleotides*
Explanation: Nucleic acids like DNA and RNA are long chains (polymers) made of repeating units called nucleotides.
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6. The three components of a nucleotide are ________, ________, and ________.
✔ Answer: *Phosphate group*, *sugar*, and *nitrogenous base*
Explanation: Each nucleotide consists of:
- A phosphate group,
- A five-carbon sugar (deoxyribose in DNA, ribose in RNA),
- And a nitrogen-containing base (adenine, thymine, cytosine, guanine in DNA).
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7. The sugar in DNA is ________.
✔ Answer: *Deoxyribose*
Explanation: DNA contains deoxyribose sugar, which lacks one oxygen atom compared to ribose (found in RNA).
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8. The four bases in DNA are ________, ________, ________, and ________.
✔ Answer: *Adenine*, *Thymine*, *Cytosine*, and *Guanine*
Explanation: These are the four nitrogenous bases found in DNA. Adenine and Guanine are purines; Thymine and Cytosine are pyrimidines.
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9. In RNA thymine is replaced by ________.
✔ Answer: *Uracil*
Explanation: RNA uses uracil instead of thymine. Uracil pairs with adenine in RNA, just like thymine does in DNA.
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10. What holds the two nucleotide strands together in DNA?
✔ Answer: *Hydrogen bonds between nitrogenous bases*
Explanation: Hydrogen bonds form between complementary nitrogenous bases on opposite strands. These weak bonds allow the strands to separate during processes like replication.
---
11. How do the bases pair in DNA?
✔ Answer:
Adenine always pairs with Thymine
And
Cytosine always pairs with Guanine
Explanation: This is known as complementary base pairing.
- A (adenine) pairs with T (thymine) via two hydrogen bonds.
- C (cytosine) pairs with G (guanine) via three hydrogen bonds.
This specific pairing ensures accurate copying of genetic information.
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✔ Final Answer Summary:
| Question | Answer |
|--------|--------|
| 1 | DNA and RNA |
| 2 | Double helix |
| 3 | Sugar and phosphate groups |
| 4 | Nitrogenous bases |
| 5 | Nucleotides |
| 6 | Phosphate group, sugar, nitrogenous base |
| 7 | Deoxyribose |
| 8 | Adenine, Thymine, Cytosine, Guanine |
| 9 | Uracil |
| 10 | Hydrogen bonds between nitrogenous bases |
| 11 | Adenine → Thymine; Cytosine → Guanine |
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Parent Tip: Review the logic above to help your child master the concept of nucleic acids worksheets.
