Download IB2.14.3 Building a protein

IB2.14.3 Building a protein
Building a protein
© Oxford University Press 2011
IB2.14.3 Building a protein
All the basic structural material of the human body is made of
proteins. Skin, muscles, bone, cartilage, ligaments and cell
membranes all contain a lot of protein. In addition, other proteins
do important jobs in cells.
All protein molecules contain the elements:
 Carbon
 Oxygen
 Hydrogen
 Nitrogen
In addition, some also contain sulphur.
25% of the mass of each human cell is protein.
© Oxford University Press 2011
IB2.14.3 Building a protein
Proteins are big molecules. They are made of smaller molecules
called amino acids. There are 20 different types of amino acids.
Each amino acid is a combination of carbon, oxygen, hydrogen,
nitrogen and sulphur atoms.
© Oxford University Press 2011
IB2.14.3 Building a protein
The amino acids
join together to
make long
chains. These
are the proteins,
of which there
are millions of
different kinds.
Genes specify
exactly how the
different amino
acids are put
together.
© Oxford University Press 2011
IB2.14.3 Building a protein
These long chains then fold up into particular (specific) shapes. Each type
of protein has a specific shape which dictates which particular function it
will carry out. Another molecule with a particular shape can fit into it.
© Oxford University Press 2011