dna by c. stephen murray. all life stores its genetic code in a molecule called dna
TRANSCRIPT
DNA
by C. Stephen Murray
All life stores its genetic code in a molecule called DNA.
All life stores its genetic code in a molecule called DNA.
Phosphate and deoxyribose make up the side.
P
P
P
O
O
O
1
23
4
5
5
3
3
5
now it’s a nucleotide.
P
P
P
O
O
O
1
23
4
5
5
3
3
5
G C
Add a nitrogen base –
Many make a double helix, if you add another side.
Sugar phosphate backbone (side)
Nitrogen base pairs
Nitrogen base
Here in the nucleus the DNA must remain
Before it takes a ride it must transcribe to the messenger RNA.
All life moves its genetic code to the ribosomes as mRNA.
Ribosomes are the little dots.
All life moves its genetic code to the ribosomes as mRNA.
nucleus
ribosomes
mRNA
DNA
Phosphate and just ribose make up the side.
P
P
P
O
O
O
1
23
4
5
5
3
3
5
makes it a nucleotide.
P
P
P
O
O
O
1
23
4
5
5
3
3
5
G C
Of course a nitrogen base –
But mRNA is not a ladder, for it has only 1 side.
The mRNA goes to the ribosome where the proteins must be formed.
nucleus
ribosomes
mRNA
DNA
But before they can be made it must translate to the transfer RNA.
Translation
Proteins are formed in the ribosomes with the help of the tRNA.
Proteins are formed in the ribosomes when amino acids carried
by each tRNA combine!
So where is this genetic code that distinguishes you from me?
It’s in the sequence of the nitrogen bases that together form our genes.
ATTCGATCGGACT
Nitrogen base sequence
Genes form chromosomes
When it makes a mistake when it replicates this is when DNA can mutate.
Original – ATTCGATCGGACT
Mutation - ATTGATCGGACT
“C” was deleted
Original – ATTCGATCGGACT
Mutation - ATTCGATACGGACT
“A” was inserted
But if it doesn’t pass to the offspring it doesn’t really matter at all.
DNA
Mutation to ribosomes
No problem
Mutation to egg or sperm
Passes to offspring
When it replicates each nitrogen base always has to pair in a certain way.
Original1 DNA
Replicas2 DNAs
For Adenine pairs with Thymine
And Cytosine pairs with Guanine
C A GT A
G T CA T
Unless its RNA
C A GU A
G T CA T
then Uracil replaces Thymine.
DNA
mRNA
All life stores its genetic code in a molecule called DNA.
All life stores its genetic code in a molecule called DNA.