DNA

DNA

STRUCTURE OF DNA
•DNA is structured like a ladder that has been twisted.
•We call this shape double helix.
•It is made from repeating units called NUCLEOTIDE,
which makes DNA and POLYMER.
STRUCTURE OF NUCLEOTIDE
Each nucleotide is made from 3 parts:
•Sugar (deoxyribose)
•Phosphate
•Base
•The sugar and the phosphate make the 2 sides of the ladder.
•The bases make the steps of the ladder.

THE BASES IN DNA

There are 4 different bases in DNA:

•A - Adenine
•T - Thymine
•C - Cytosine
•G – Guanine
It is the bases that make up the human genetic code.
There are roughly 3.3 billion base pairs in our genetic code.
Genes vary in length from a few hundred bases to more than 2 million.
THE GENETIC CODE
 Bases always pair up in the same way creating 2 strands (each side of the ladder)
The 2 strands are said to be COMPLEMENTARY.
How do the bases pair up? 

https://www.youtube.com/watch?v=zwibgNGe4aY click on this for summary.


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