DNA and DNA replication Flashcards
1
Q
What is the structure of DNA and who discovered it
A
- discovered by Watson and Crick
- consists of two polynucleotide strands joined together by hydrogen bonding to form a double helix
- phosphodiester bonds between nucleotides formed in condensation reactions
2
Q
How does DNA replicate
A
semi - conservative replication:
- DNA helicase unzips the 2 strands by breaking the hydrogen bonds and both strands become templates
- free nucleotides are attracted to complimentary bases on the templates by hydrogen bonding
- once the nucleotides are lined up they are joined together by phosphodiester bonds by DNA polymerase via condensation reactions
- 2 identical molecules of DNA are formed each one composed of one original strand
3
Q
What are some functions of DNA
A
- genes are sections of DNA that code for a specific sequence of polypeptide determining the nature and development of organisms
- DNA has the ability to self replicate which is essential for cell division
- changes in the base sequence (mutation) could occur, providing genetic diversity
