1. Genetics Information
Biologists discovered that during cell division chromosomes are separated from
each other so that each emerging cell that separates the same number of
chromosomes in the original cell which indicates that the chromosomes that carry
genetic information units in the qualities of the gene known as gene name.
Chromosomes introduces two main components are the DNA and proteins.
Scientists initially thought that the proteins are carrying genetic information due to a
variety of proteins consists of a group of molecules where it enters in the
composition of 20 different amino acids, while the DNA consists of four nucleotides
only.
In the forties this theory wrong has emerged as it became clear that DNA is the one
who carries the genetic information.
2. RNA structure
Ribonucleic Acid
RNA is a polymer of ribonucleotides linked
together by
phosphodiester linkage
There are also three main component
(aPhosphate Group
(bSugar(Ribose)
(cAnd Nitrogenous base
The Nitrogenous Bases
They are divided into two groups:
.iPurine
.iiPyrimidine
Purines (made of a 6 member ring, fused to a
5 member ring)
Adenine
Guanine
Pyrimidine (made of a 6 member ring)
Cytosine
Uracil
3. Nucleotide
HH
OH
O
CH2
Base
Phosphate
Ribose
OH
5′
4′ 1′
3′ 2′
O
O
P
O–
O
HH
A, G, C or
U
RNA Nucleotide
RNA Structure
Nucleotides are formed by the
condensation of a sugar,
phosphate and one of the 4
bases
The following illustration
represents one nucleotide
4. Type of RNA
1) mRNA (massenger).
2) tRNA (transever).
3) rRNA (ribsomal).
5. Genetic code
The genetic code is the set of rules by which
information encoded in genetic material (DNA or
RNA sequences) is translated into proteins (amino
acid sequences) by living cells
