Unit 1(1.2)- Structure And Replication Of DNA Flashcards
What is DNA an example of?
A nucleic acid.
What are the four bases of DNA?
Thymine, Adenine, Guanine and Cytosine.
What are the repeating units of DNA called?
Nucleotides.
What three things do a nucleotide of DNA contain?
A phosphate, a deoxyribose and a base.
What are the nucleotides joined by?
Sugar-phosphate bonds.
What do the sugar-phosphate bonds form?
A sugar-phosphate backbone.
How do the bases pair?
Adenine and Thymine.
Guanine and Cytosine.
What are the base pairs held together by?
Weak hydrogen bonds.
The base pairs are held together by weak hydrogen bonds, forming two complementary strands. The two strands wind round each other in a spiral form to form what?
A double helix.
What direction do the two strands run and what is this called?
Opposite directions and anti-parallel.
What end is the deoxyribose at on each strand and what end is the phosphate at on each strand?
Deoxyribose-3’
Phosphate-5’
What do chromosomes consist of?
DNA that is tightly coiled around associated proteins.
Why do chromosomes consist of DNA that is tightly coiled around associated proteins?
So that all 2 metres of it can fit into the nucleus of the cell.
Where do all cells store their genetic information,
In the base sequence of DNA.
What is the genotype determined by?
The sequence of DNA bases.
