the

Genetic code

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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