DNA Flashcards
What is joined in strands?
Nucleotides
Describe the structure of the DNA strands
Anti-parallel - they run in opposite directions
Each strand has a 3’end and a 5’end
Where is DNA located?
In the membrane bound nucleus
How is DNA organised?
Coiled up into ‘spools’
How is each spool composed?
Each spool is composed of proteins, with DNA wrapped tightly around them
What are the requirements for DNA replication?
DNA ATP DNA polymerase 4 types of nucleotide - a,t,c,g Primer - a short sequence of nucleotides Ligase
Name steps 1,2 and 3 of DNA replication
The DNA molecule unwinds
Hydrogen bonds break, unzipping the molecule and exposing the bases of both DNA strands
A primer attaches to one end of each exposed DNA template strand
Name steps 4,5 and 6 of DNA replication
This initiates DNA polymerase to add free complementary DNA nucleotides to the 3’end of the growing strand
Hydrogen bonds form between the bases
Strong chemical bonds form between the phosphate and the deoxyribose sugar of adjacent nucleotides
Name steps 7 and 8 of DNA replication
Ligament enzyme joins fragments to form a complete strand
Each replicated DNA molecule is a newly synthesised strand
What is DNA made up of?
Sub units called nucleotides
To which end does DNA polymerase add nucleotides to?
The 3’end of the strand
To which end does DNA polymerase add nucleotides to?
The 3’end of the strand
