Structure and replication of DNA Flashcards
What information in inherited
Genetic information is inherited
DNA is a substance that does what
DNA is a substance which encodes the genetic information of inheritance in a chemical language
How to describe DNA
DNA is a very long, double - stranded molecule in the shape of a double helix
What is each strand of DNA made up from
Each strand of DNA is made up of chemical units called nucleotides
What three parts make up a DNA nucleotide
DNA nucleotide is made up from deoxyribose, phosphate, and a base
what do deoxyribose molecules have
Deoxyribose molecules have five carbon atoms numbered 1 to 5
What happens between nucleotide phosphates and the carbon molecules
The phosphate of one nucleotide joins to the carbon 5’5 and is linked to the carbon 3’3 of the next nucleotide in the strand
This produces a 3’-5’ sugar-phosphate-backbone
What are the four different DNA bases called
A - adenine
C - cytosine
T - thymine
G - guanine
How are the strands joined together
The nucleotides of one strand of DNA are linked to the nucleotides on the next strand of DNA through their complementary base pairs
What are the pairs
Adenine - Thymine
(Adenine - Uracil)
Guanine - Cytosine
How are base pairs held together
Base pairs are held together by weak hydrogen bonds
What does each strand have
Each strand has a sugar-phosphate backbone which has a 3’ end that starts with a deoxyribose molecule and a 5’ end that finishes with a phosphate molecule
What way do the two strands of a DNA molecule run
The two strands of a DNA molecule run in opposite directions and are antiparallel to each other
What forms the genetic code
The base sequence of DNA forms the genetic code
When do DNA molecules replicate
DNA molecules replicate before cell division