Proteins Flashcards
What are amino acids?
The monomers from which proteins are made
What are amino acids made from?
- Amine group (NH2)
- Carboxylic acid group (-COOH)
- R group (carbon containing chain)
How many bases code for 1 amino acid?
3 bases
How are dipeptides formed?
Through a condensation reaction where a peptide bond is formed between the amine group of one amino acid and the carboxyl group of another, releasing a water molecule
What are the four different structures of proteins?
- Primary
- Secondary
- Tertiary
- Quaternary
Describe the primary structure of proteins
The sequence of amino acids in a polypeptide chain
Describe the secondary structure of proteins
The folding of a polypeptide chain into alpha helices or beta pleated sheets due to the sequence of the amino acids in the primary structure
What bond holds the secondary structure in place?
Hydrogen bonds
Describe the tertiary structure of proteins
The further folding of the secondary structure which forms a unique 3D shape due to R group interactions
Describe the quaternary structure of proteins
A protein made up of more than one polypeptide chain
What are the 4 types of R group?
- Positively charged
- Negatively charged
- Non-polar
- Polar
What are the different type of bonds within tertiary and quaternary proteins?
- Disulphide bonds/bridges
- Hydrophobic & hydrophilic interactions
- Hydrogen bonds
- Ionic bonds
Where are hydrogen bonds formed?
Hydrogen bonds are formed between a hydrogen of one amino acid and an oxygen of another
Where are ionic bonds found?
Between amino acids with oppositely charged R groups
Where are disulphide bonds/bridges found?
Between Rgroups that contain a sulfur
Where are hydrophobic amino acids found?
In the centre of proteins as they repel water due to having non-polar R groups
Where are hydrophilic amino acids found?
On the surface of proteins as they are attracted to water due to having polar R groups
What are globular proteins?
Globular proteins are compact, spherical proteins that are soluble in water
What are fibrous proteins?
Fibrous proteins are long proteins that are insoluble in water and play important structural roles in the body
