hello everyone
quit back a mr. basics here so let's
talk about genetic code the DNA act as a
genetic material to encodes all the
information required to encode a protein
the specific region of DNA that encodes
the genetic information is called a gene
and there can be several genes in the
genome for example equal AI has roughly
4,500 genes while humans have 30,000
genes it's usually by the process of
transcription genetic information in the
DNA flows in RNA also known as the
messenger RNA or mRNA the information
contained in mRNA is further used by the
translational machinery to make proteins
this flow of information from DNA to RNA
and protein is also known as central
dogma of molecular biology this was
given by Francis Crick in the year 1958
the genetic code genetic code is a
particular sequence of nucleotide that
tells which amino acids are to be linked
together to form a protein
the genetic code consists of 64 Triplets
of nucleotides that codes for 20 amino
acids each of these triplets are known
as codons now as there are 64 codons and
only 20 amino acids a single amino acid
can be coded by more than one codon this
property of genetic code is known as
degeneracy for example amino acid
proline can be coded by CCU si si si si
si a and C c/g however a single codon
will all be scored for a single amino
acid for example CCU all the scores for
prolene Aug always codes for methionine
this property of genetic code is called
non ambiguity the genetic code is
non-overlapping which means after
reading one triplet the reading frame
shift over the other three nucleotides
the genetic code is comma less which
means there is no extra nucleotide
between the codons the genetic code has
start and stop codons Aug is usually a
start codon that codes for methionine
and stop codon are you a a
UAG and UGA a the stop codons are also
known as nonsense codon as they do not
code for any amino acid the genetic code
is nearly universal which means in the
same in humans bacteria plants and
amphibians however there are some
exceptions in mitochondrial genome
single-celled eukaryotes and some
bacteria the first two bases of the
genetic code are same while a deterred
position the base Meeropol
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