Biology triplet code help me please?!

Watch this thread
Love123443
Badges: 6
Rep:
? You'll earn badges for being active around the site. Rep gems come when your posts are rated by other community members.
#1
Report Thread starter 5 years ago
#1
Can someone please explain why theres a triplet code, i mean it doesnt make sense because it says because it can code for 20 amino acids but how can it when it apparently makes 64 different combinations? I am so confused with this triplet code stuff someone please help me
0
reply
SANTR
Badges: 8
Rep:
? You'll earn badges for being active around the site. Rep gems come when your posts are rated by other community members.
#2
Report 5 years ago
#2
(Original post by Love123443)
Can someone please explain why theres a triplet code, i mean it doesnt make sense because it says because it can code for 20 amino acids but how can it when it apparently makes 64 different combinations? I am so confused with this triplet code stuff someone please help me
64 combinations of triplet bases. Each amino acid is coded by more than one codon (triplet bases), due to the degenerate nature of the genetic code. E.g ATC may code for amino acid A and GAC may also code for amino acid A.
0
reply
Jehaan
Badges: 19
Rep:
? You'll earn badges for being active around the site. Rep gems come when your posts are rated by other community members.
#3
Report 5 years ago
#3
This is because triplet code is degenerate. This means that different codes can end up as the same amino acid. For example, see the table attached. Every amino acid except one has more than one code that will produce that amino acid. Like UCU will make serine but UCC will also make serine. An advantage of this is if the DNA mutates then there might not be any noticeable difference. For example if the code is supposed to be UCU but it mutates to UCC then there will be no effect on the phenotype as there is no difference
Hope that helps!
0
reply
Jehaan
Badges: 19
Rep:
? You'll earn badges for being active around the site. Rep gems come when your posts are rated by other community members.
#4
Report 5 years ago
#4
Sorry the table won't attach just put triplet code degenerate into google images and you'll get what I mean
Attached files
0
reply
Reality Check
Badges: 22
Rep:
? You'll earn badges for being active around the site. Rep gems come when your posts are rated by other community members.
#5
Report 5 years ago
#5
Also note that not every combination of 3 bases encodes for an amino acid. There are 'STOP' codons which signal for the termination of translation: these are UAG, UGA and UAA in RNA.
0
reply
Akbar2k7
Badges: 20
Rep:
? You'll earn badges for being active around the site. Rep gems come when your posts are rated by other community members.
#6
Report 5 years ago
#6
4 possible bases => A or T/U or C or G

3 permutations '1' or '2' or '3'

4^3 = 64

DNA is a base 4 system with 3 values.

64 is the potential codes you could make with such a system.

DNA only needs to have information for around 20, amino acids and like mentioned 'STOP' codons.

So in Reality a lot of this 'potential code' is recycled meaning 2 values for the same amino acid. This makes the code Degenerate.

Think of it like this you have 64 boxes but 20 varieties of toys some boxes can contain the same type of toy meaning balls in 4 boxes(Glycine has 4 triplet codes) or blocks in 2 different boxes (Tyrosine having 2 triplet codes). You can fill your 64 boxes without 64 different toy varieties.

Hope it helps.
0
reply
X

Quick Reply

Attached files
Write a reply...
Reply
new posts
Back
to top
Latest
My Feed

See more of what you like on
The Student Room

You can personalise what you see on TSR. Tell us a little about yourself to get started.

Personalise

Has advance information helped during your exams?

Yes (143)
66.51%
No (47)
21.86%
I didn't use it to prepare (25)
11.63%

Watched Threads

View All