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How Protein Synthesis Works

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protein synthesis is just a fancy way of

saying making proteins and just like if

you want to make a certain meal you need

the instructions in order to do it

a recipe book gives the instructions to

make for example a kick you read those

instructions and you're able to make a

cake in exactly the same way genes give

the information to make proteins there's

little strand of DNA which makes up a

gene gives the information to string

together a bunch of amino acids and a

bunch of amino acids strung together is

essentially what makes a protein DNA has

this kind of appearance it's made up of

four chunks and those are a C G and T

and only those four and they're all

paired together here you can see a base

pair of a and T below that is a C and a

G below that is a G and a C and it's

always structured together like this

here will always be with T and T will

always be with a C will always be with G

and G will always be with C and air

would never pair with G for example next

thing to notice is that these are

grouped in three

this is how they code for the amino

acids it's every chunk of three bits of

DNA that has the information for which

amino acid belongs next in the protein

chain now when it comes time to give the

information to create a protein the DNA

can't really go anywhere and it can't go

anywhere to be read because it needs to

be protected and it remains within the

nucleus so here's what happens first of

all part of that string will kind of

move away it unzips just for a little

while and leaves part of itself exposed

and then this next piece which is kind

of like DNA comes and matches itself up

the air joins with the T the C joins

with the G and this continues onwards

now this is not actually DNA this is

called RNA

and this particular type is M RNA which

means messenger RNA messenger RNA

basically takes the message of what

information is contained in the DNA

inside of the nucleus notice that with

RNA molecules there is no base T T is

just replaced with you but it's

basically doing the same job now what

happens is the mRNA molecule is going to

leave the nucleus and it's going to go

to a ribosome and ribosomes are the site

of protein synthesis and next we need

another important RNA molecule this one

is tRNA now tRNA has three bases

attached to it and an amino acid at the

top now the specific amino acid that's

attached depends on which three bases

there are at the bottom remember that

we've got lots and lots of different

types of amino acids and it's the

specific structure and order of those

amino acids in a chain that determines

which type of protein is being produced

what happens is this tRNA molecule comes

in the lines at the correct place and

this determines where that amino acid is

going to appear in the chain this will

happen again at the next place and this

determines the next amino acid that they

will be in the chain and they get bonded

together this will continue on and on

and on and on bearing in mind that DNA

and RNA molecules are much much much

longer than they are shown here and

ultimately what we end up with is a

string of thousands of amino acids and

thousands of amino acids together make

up a protein

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