2. PROTEINS
Structure:
A protein molecule is made of lots of building blocks
linked together in chains.
The building blocks are called AMINO ACIDS.
The links between them are called PEPTIDE BONDS.
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3. About twenty amino acids exist in nature. These include
phenylalanine, leucine, serine, cysteine and so on…
Not all proteins are the same. Proteins can be different
because of the different amino acids making them up
and their order.
PROTEINS
A small protein molecule may be
made from a chain of a hundred
amino acids.
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4. Different amino acids:
The long chains of amino acids fold to give each type of
protein a specific shape.
These folds happen when amino acids which are not
neighbours form peptide bonds together.
These are called CROSS LINKAGES.
PROTEINS
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5. Proteins act as:
1. Structural parts of tissue such as muscle
2. Hormones
3. Antibodies
4. Enzymes (biological catalysts)
PROTEINS
Some proteins are tough and fibre – like. They form
the main structures of the body: bones, muscles,
skin and so on.
Others exist in solution, ex in blood and in our cells.
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6. Heating the protein above 40 degrees Celsius will cause
it to change shape; we say the protein has been
DENATURED. This can make it lose its functions.
PROTEINS
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7. Heating the protein above 40 degrees Celsius will cause
it to change shape; we say the protein has been
DENATURED. This can make it lose its functions.
PROTEINS
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