Name _________________________    

Due Date: __________________

        Scientists utilize models to help them better understand a concept that may be too small or too large to portray physically. The use of models help scientist to better understand the structure of DNA and the processes involved on a microscopic level.

For this assignment you will be making a three dimensional model of DNA. You may use any materials such as clay, pipe cleaners, styrofoam, felt, and so on but please no perishable food items. Below are the instructions for this project. After completing the model, there are a few questions that need to be answered on the back of this sheet. The answers to these questions are due the day you turn in your model. Not turning this sheet in with the model will result in a losing 15 points for failing to answer the questions.

        Your model of DNA must include the following aspects, but is not limited to the following:

  1. Nucleotides joined in a polymer
  2. Sugar-phosphate backbone
  3. Bases on the inside of the helix joined by hydrogen bonds
  4. Your model must show one complete turn of the helix
  5. At least 10 base pairs
  6. Correct base pairing
  7. Correct positioning of bases in relation to the backbone
  8. Key indicating which structures are what

Component

Points Possible

Score

Backbone

10

 

Base Orientation

10

 

10 Base / turn

10

 

Correct base pairs

10

 

Key clearly identified different parts of DNA

15

 

Neatness of Model

10

 

Questions answered correctly on back

15

 

Total Points

80 points

 

 

 

Answer the following questions. You may want to look at your model to help you visualize the answers.

 

1. What is a nucleotide? (2 points)

 

 

2. What are the three building blocks of a nucleotide? (3 point)

 

 

3. How many different nitrogen bases are found in DNA? (1 point)

 

4. How do the bases pair up? Spell them out. (2 points)

 

 

5. Does one strand of DNA offer enough clues for assembling its complementary strand? If so, how? And why is this important? Think about cell division. (4 points)

 

 

 

6. What is the base order for the complementary DNA strand to the sequence ATTGCAAGGCC? (3 points)