Practice applying DNA base pairing rules using the mnemonics Apple Tree for A-T and Car Garage for C-G.
Read each problem carefully. Use the DNA base pairing rules: adenine pairs with thymine, and cytosine pairs with guanine. Show your work in the space provided.
Practice matching A with T and C with G in DNA sequences
Biology - Grade 9-12
- 1
Use the Apple Tree and Car Garage mnemonics to explain the two DNA base pairing rules.
- 2
Write the complementary DNA strand for this sequence: ATCG
- 3
Write the complementary DNA strand for this sequence: GCTA
- 4
A section of DNA has the sequence AAGTCC. Write the complementary DNA strand.
- 5
A student writes that the complement of TACG is ATGC. Check the student's answer and explain whether it is correct.
- 6
A student writes that the complement of CCGT is GGTA. Identify the mistake and write the correct complementary strand.
- 7
Complete the missing bases in this DNA pair: Original strand: A T C G A. Complementary strand: _ _ _ _ _.
- 8
Complete the missing bases in this DNA pair: Original strand: G C T A C G. Complementary strand: _ _ _ _ _ _.
- 9
A double-stranded DNA segment contains 18 adenine bases. How many thymine bases should it contain? Explain your answer.
- 10
A double-stranded DNA segment contains 24 cytosine bases. How many guanine bases should it contain? Explain your answer.
- 11
In a DNA sample, 30 percent of the bases are adenine. What percent of the bases are thymine? What percent are cytosine and guanine combined?
- 12
Look at this partially paired DNA segment: Top strand: A C G T T A. Bottom strand: T G C A A T. Explain why this is a correctly paired DNA segment.