Proteins

Question 1

What is an amino acid

Answer 1

Monomer which makes up proteins. Central carbon atom bonded to carboxylic acid, amino group, hydrogen atom and R group

Question 2

What is an amine group

Answer 2

The -NH2 group of amino acid

Question 3

What is carboxyl group

Answer 3

The -COOH group of an amino acid

Question 4

What is disulphide bridge?

Answer 4

Bond formed between sulphur atoms in R groups of amino acids

Question 5

What is a hydrogen bond?

Answer 5

Chemical bond form between the positive charge on a hydrogen atom and the negative charge on another atom of adjacent molecule often between negative oxygen and positive hydrogen

Question 6

What is ionic bond?

Answer 6

Bond between a positive iron, which has lost an electron and a negative iron which is gained electrons

Question 7

What is a peptide bond?

Answer 7

Type of bond that is formed between two amino acids

Question 8

What is a polypeptide?

Answer 8

Many immuno acids joined together by peptide bonds

Question 9

What is the primary protein structure?

Answer 9

Sequence of amino acids that make up the polypeptides of a protein

Question 10

What is a protein?

Answer 10

Polymer which is made up of amino acids linked by peptide bonds may also contain prosthetic groups as part of its return quaternary structure

Question 11

What is the quaternary protein structure?

Answer 11

Number of polypeptide chains linked together and sometimes associated with non-protein groups to form protein

Question 12

What is R group?

Answer 12

Each of the 20 immuno acids have a different R group determines the bonding that the amino acid can carry out

Question 13

What is secondary protein structure?

Answer 13

The way in which the chain of amino acid of the polypeptides of, the protein is folded

Question 14

What is the tertiary protein structure?

Answer 14

Folding of a whole polypeptide chain in a precise way, as determined by the immuno acid of which it is composed

Question 15

Amino acids info

Answer 15

Monomers that make up protein. Only 20 amino acids present in all forms and the different combinations of these determines the shape and structure of each protein as well as its properties.

Question 16

What happens when two amino acids join?

Answer 16

They join via a condensation reaction, and a peptide bond is formed, easing a water molecule. Two amino acids joined together is known as a dipeptide.

Question 17

What is a polypeptide

Answer 17

More than two amino acids joined together

Question 18

How are dipeptides and polypeptides broken down?

Answer 18

Through hydrolysis

Question 19

What are the different levels of protein structure?

Answer 19

1. Primary
2. Secondary
3. Tertiary.
4. Query.

Question 20

Primary structure, description

Answer 20

Number and sequence of amino acids in the polypeptide chain. Can determine the 3-D shape or tertiary structure and can therefore affect the shape of the active sites and enzymes.

Question 21

Secondary structure, description

Answer 21

Hydrogen bonds form between amino acids in the chain. This causes it to coil into an alpha helix or fold into beta pleated sheets. The many hydrogen bonds make these structures stable. Most channel proteins are made of alpha Helices. 

Question 22

Tertiary structure, description

Answer 22

This is a 3-D shape of the polypeptide chain. It creates a specific shape due to the sequence of amino acids in the chain is a hydrogen bonds, ionic bonds and disulphide bridges (covalent bonds) form between R groups. A change to the sequence of amino acids would affect the secondary and tertiary structure of these bonds would form in different places. All enzymes antibodies and some hormones have tertiary structure

Question 23

Quaternary structure, description

Answer 23

If proteins are made of more than one polypeptide chain, then they are jointed together to create quaternary structure. Antibodies and haemoglobin are examples of these other non-protein groups may also be associated e.g. the haem group in haemoglobin 

Question 24

What are fibrous proteins?

Answer 24

Long strands of polypeptide chains that have crossed linkage due to hydrogen bonds. They are insoluble. Little Or no tertiary structure. Limited number of amino acids with the sequence usually being highly repetitive 

Question 25

Examples of fibrous proteins

Answer 25

Collagen, elastin and keratin

Question 26

Collagen info

Answer 26

Three polypeptide chains has lots of covalent bonds, long, strong, flexible and insoluble chains lie close together

Question 27

Elastin info

Answer 27

Insoluble, flexible, stretches, long, found in alveoli, blood vessels and skin

Question 28

Keratin info

Answer 28

Long insoluble found in hair ,nails, claws, hooves and skin

Question 29

What are globular proteins?

Answer 29

Spherical proteins that are somewhat water, soluble, and have a compact structure, one of the common protein types.

Question 30

Pepsin info

Answer 30

Mainly beta sheets with Alpha helixes has two disulphide bridges. Tertiary structure, forms, active sites as its protease enzyme.

Question 31

Insulin info

Answer 31

Transportable as it soluble. No beta sheets. Compact. Tertiary structure. hydrophobic core, hydrophilic exterior, lowers blood glucose

Question 32

Haemoglobin info

Answer 32

Mostly alpha helixes. Compact. For polypeptide chains 2 alpha 2 beta.

Question 33

3 globular protein

Answer 33

Pepsin, insulin and haemoglobin