DNA & Proteins
DNA (Deoxyribonucleic Acid) = This molecule that is 3 billion monomers in length is the
Instruction Book for Life! More specifically it is the recipe book for how to make
proteins. That is all DNA codes for is how to make proteins!!
The monomer of DNA is called a Nucleotide. Each nucleotide has 3 parts –
Phosphate, Sugar (deoxyribose) & Nitrogen Base.
*
Draw a picture of a nucleotide labeling the 3 parts:
*Draw a picture of a polynucleotide that has 3 monomers attached
:
Proteins (Polypeptides) = Proteins form all structures, enzymes, antibodies, pigments, etc.
in living things. In short – Proteins make everything and do everything in all organisms!!!
The monomer of a protein is called an Amino Acid. There are 20 different amino
acids that can link together to form long polypeptides up to 100,000 amino acids long. Just
think – with 26 letters in the alphabet, how many words, sentences, paragraphs, etc. can be
formed? The same diversity occurs when organizing 20 amino acids to form all of the
different proteins that are a part of living things!!!
*
How many different Amino Acids are there?
*What is an Essential Amino Acid? How many are there?
DNA & Proteins (“You can‟t bake a cookie without a recipe!!!”)
The DNA code for how to make proteins is “written” in the 4 Nitrogen Bases.
There are 4 Bases in DNA – G, C, A & T. Polynucleotides are millions of nucleotides long,
meaning millions of GCAT‟s in every combination possible. Every 3 bases on DNA (called
a codon) codes for 1 amino acid of a protein - For example TAG codes for something
different than CAT. (DNA looks like a ladder. The sides of DNA are simply the sugar and phosphate
alternating in a set pattern, so there is no “code” on this part).
The question that most people have is „how can 4 bases (GCAT) be code‟ for all of
the difference we see in each other, let alone the differences we see in all life forms from
bacteria, to flowers, to elephants!!! The answer is simple, if you know the secret genetic
code! Complete the activity on the back to learn the secret of the Biology Code!!!
