1. Functional Variety of Proteins
Proteins: organic compounds containing carbon (C), hydrogen (H), oxygen (O), nitrogen (N) and sometimes sulphur (S).

2. What I need to know:-
Proteins are held in 3d shape
Proteins are held by bonds
Types of proteins and their functions

3. Bonds in proteins
The product – POLYPEPTIDE CHAIN (eventually a protein)
1. Peptide bonds
Proteins are build up of sub-units called amino acids. These are joined together by chemical links called PEPTIDE BONDS.
AA1
AA2
tRNA
tRNA
The sequence of amino acids determines the protein’s structure and function. U C G A G C A G C U C G A G G

4. 2. Hydrogen bonds
Weak hydrogen bonds form between amino acids in a polypeptide chain causing the chain to coil into a spiral.
3. Other linkages
There are different cross-connections that bridges sulphur atoms with hydrogen bonds. These are important because they determine the final structure of the protein and so determine the function of the protein. They lead to the formation of FIBROUS or GLOBULAR proteins.

6. Conjugated (Globular + non protein part)
Types of proteins
A HUUUUGEEE amount of proteins exist in living things – the human body has 10,000 +.
They are classified as either:
Fibrous
Globular
Conjugated (Globular + non protein part)

7. Fibrous proteins
FIBROUS proteins are formed by several spiral-shaped polypeptide molecules link together giving it a rope-like structure.
Example:
Collagen – found in bone providing inelastic, rigid support.

8. Globular protein Enzymes Structural proteins Hormones Antibodies
GLOBULAR proteins are formed with polypeptide chains fold into a spherical shape. This type of protein are vital for all living cells and perform many functions:
Enzymes
Structural proteins
Hormones
Antibodies .

10. Conjugated proteins
These proteins are globular but also consist of a non-protein chemical.
Examples:
GLYCOPROTEIN - made up of protein and a carbohydrate. For example, mucus that helps lubricate and protect parts of the body.
HAEMOGLOBIN – pigment that transports oxygen in blood. Consists of the protein globin and haem (non-protein containing iron).