U3 Flashcards
1
Q
What are the 3 components of nucleotides?
A
- phosphoric acid (phosphate group)
- 5 carbon sugar (deoxyribose)
- 1 of 4 nitrogenous bases
2
Q
What is the double strand of the double helix held in place by?
A
hydrogen bonds
3
Q
What are the 3 functions of DNA?
A
- replicates itself 2. controls the activity of the cell 3. mutations for variety in living things
4
Q
Explain the key components in the 4 steps of DNA replication
A
- An enzyme untwists the strands, helicase breaks the weak hydrogen bonds between base pairs to unzip DNA
- DNA polymerase helps present nucleotides complementary base pair
- ligase glues the alternating sugar phosphate backbone together
- Two identical DNA molecules wind back up into a helix
5
Q
*look at page 22
A
6
Q
A