Protein Synthesis. Help! I broke a nail!. What are nails made of? A protein called keratin How does your body make a new nail to replace the one that broke off? The body needs to make more keratin ( Keratin is a protein. Remember: If it ends in “in” it is a prote in)
(Keratin is a protein. Remember: If it ends in “in” it is a protein)
In our bodies the making of new protein (like keratin) is called protein synthesis
DNA in the cell
from food! (protein that you eat is broken down into amino acids, the amino acids are then used to build the needed protein)
Enzymes (like RNA polymerase) and RNA
What do you call a region of DNA like this that “codes” for something?
REMEMBER: The DNA code is made up of nucleotides, A, T, C and G A pairs with T
C pairs with G
A T G T G G A G T C A C G GG T G A
T A C A C C T C A G T G C CC A C T
Only one side of the DNA strand is “read”. This side is called the template strand. Let’s say its this one
Here is the tricky part. DNA cannot leave the nucleus. We need to make a complimentary copy of the gene and carry the copy out of the nucleus.
A U G U G G A G U C A C G GG U G A
Before this mRNA leaves the nucleus it is edited. Certain parts of the code are cut out.
The portions removed are called _____________.
The portions that remain are called ____________.
Lets say UGG and AGU are introns.
What would the final mRNA look like?
TRANSCRIPTION IS OVER!
All of this was happening in the nucleus. Now the final mRNA transcript leaves the nucleus and arrives at a ribosome in the cytoplasm for translation.
A U G C A C G GG U G A
Use the genetic code!
METHIONINE-HISTIDINE-GLYCINE = KERATIN (JUST AS AN EXAMPLE. The actual protein is much longer)
Any change in the DNA code is called a mutation.
Sometimes the change still codes for the same amino acid and forms the same protein so there is no noticeable effect.
Other times the change results in the wrong amino acid. The necessary protein will not form. This could result in a disorder of some kind.
C. Nucleus, chromosome, gene
ALL organisms (prokaryotes do not have a nucleus but they have ribosomes)
THIS IS THE CENTRAL DOGMA OF BIOLOGY!
This is a ribosome