Made of amino acids. A chain
of which is called a
polypeptide. Peptide bonds
hold them together
Two types: fibrous and
globular. Fibrous form
bundles and globular are
folded into globe-shaped
molecules
Made up of
several thousand
amino acids
RNA
messenger, transfer
and ribosomal
Single stranded
Sugar is ribose
The base Uracil
replaces Thymine
Transcription
1) The enzyme RNA polymerase
binds to the strand and the DNA
unwinds here. The enzyme Helicase
does this.
2) Only one strand is used
and the triplets are read by an
enzyme and are corresponded
into codons.
3)When RNA polymerase
reaches the terminator
sequence, transcription
is completed.
4) The two DNA strands
rejoin
Occurs in nucleus
RNA Splicing: Introns are NOT
needed for the protein formation so
these are cut out of the strand. The
exons are then joined together to
from the final transcript of mRNA.
Translation
1) The edited mRNA
leaves the nucleus and
travels to a ribosome.
2) The ribosome
moves along the
mRNA strand and
reads the codons.
3) Each codon corresponds to a triplet in DNA,
thus coding for a particular amino acid.
4) The corresponding tRNA molecule
brings along the anti-codon and picks up
the correct amino acid along the way.
5) This continues until a STOP
codon is reached and translation
terminates. The amino acids
have now formed a chain and it
breaks off and travels to the
place it's needed.