DNA

Question 1

What does DNA consist of?

Answer 1

• Phosphate group
• Deoxyribose sugar
• Nitrogenous base (adenine, guanine, cytosine, thymine)

Question 2

How is DNA structured?

Answer 2

Deoxyribose sugar bonds with phosphate group, forming phosphodiester bonds.

Nitrogenous bases complementary to each other in antiparallel strands form hydrogen bonds with each other.

Question 3

Which nitrogenous bases are complementary to eachother?

Answer 3

• Adenine and Thymine
• Guanine and Cytosine

Question 4

What is the significance of purines and pyrimidines?

Answer 4

• Adenine and Guanines are purines
• Thymine and cytosine and pyrimidines
• Between Adenine and Thymine, 2 H bonds form
• Between Guanine and Cytosine, 3 Hydrogen bonds form

Question 5

How does replication begin (structure wise, chemistry edition)

Answer 5

• Weaker H bonds between bases more easily broken than covalent bonds in sugar phosphate backbone
• So unzip (strands break apart)
• New nucleotides from cells pair up with exposed bases, then link by sugar phosphate bonding, then helix molecules are replicated