Exploring the Basics of DNA Replication

DNA is a nucleic acid composed of four bases: thymine, adenine, cytosine, and guanine. Thymine pairs with adenine, and cytosine pairs with guanine. DNA's structure resembles a ladder, with bases as rungs and phosphates and sugars as sides. This structure allows for easy replication, where one strand forms a complementary strand. Enzymes like helicase and DNA polymerase play crucial roles in replication, which occurs during the S phase of the cell cycle to prepare for cell division in mitosis.

Which of the following is NOT a base of DNA?

• Uracil

• Cytosine

• Thymine

• Adenine

What does thymine pair with in DNA?

• Guanine

• Cytosine

• None

• Adenine

What analogy is used to describe the structure of DNA?

• Ladder

• Helix

• Spiral staircase

• Twisted rope

Which enzyme is responsible for adding nucleotides to a new DNA strand?

• Ligase

• Helicase

• RNA polymerase

• DNA polymerase

During which phase of the cell cycle does DNA replication occur?

• G2 phase

• M phase

• S phase

• G1 phase