Let’s go through each question step by step using the diagram in Model 1.
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1a. What are the three parts of a nucleotide?
Looking at the top-left part of Model 1, there’s a labeled diagram called “Nucleotide.” It shows three connected pieces:
- A circle labeled
Phosphate
- A pentagon (5-sided shape) labeled
Deoxyribose sugar
- A rectangle or other shape labeled
Nitrogen-containing base
So, the three parts are:
→ Phosphate
→ Deoxyribose sugar
→ Nitrogen-containing base
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1b. What kind of sugar is found in a nucleotide?
Right under the phosphate and next to the pentagon shape, it says:
→
Deoxyribose sugar
That’s the specific sugar in DNA nucleotides.
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1c. Which nucleotide component contains nitrogen?
The label on the right side of the nucleotide diagram points to the rectangular/odd-shaped piece and says:
→
Nitrogen-containing base
Also, the section below is titled “Nitrogen Bases,” which confirms that this part holds the nitrogen.
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1d. Name the four nitrogen bases shown in Model 1.
Under the heading “Nitrogen Bases” in Model 1, there are four shapes with names next to them:
- Adenine
- Thymine
- Guanine
- Cytosine
These are the four nitrogen bases in DNA.
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2a. Circle a single nucleotide on each side of the ladder model of DNA.
In the “Ladder Model of DNA” drawing in the middle of Model 1, you can see two vertical strands (the sides of the ladder). Each strand is made of repeating units — those are nucleotides.
Each nucleotide includes:
- One phosphate (circle)
- One deoxyribose sugar (pentagon)
- One nitrogen base (rectangle or other shape attached to the sugar)
On the left side of the ladder, pick any one complete set — for example, the topmost group: circle + pentagon + base pointing right.
On the right side of the ladder, pick any one complete set — for example, the topmost group: circle + pentagon + base pointing left.
You would draw a circle around each of those groups to show one full nucleotide per side.
*(Note: Since we’re not actually drawing here, but describing — if you were doing this on paper, you’d physically circle one nucleotide unit on the left rail and one on the right rail of the ladder.)*
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Final Answer:
1a. The three parts of a nucleotide are: phosphate, deoxyribose sugar, and nitrogen-containing base.
1b. The sugar found in a nucleotide is deoxyribose sugar.
1c. The component that contains nitrogen is the nitrogen-containing base.
1d. The four nitrogen bases are: adenine, thymine, guanine, and cytosine.
2a. On the ladder model, circle one complete nucleotide (phosphate + sugar + base) on the left side and one on the right side.
Parent Tip: Review the logic above to help your child master the concept of dna structure worksheet high school.
