Antibody

Question 1

Variable region

Answer 1

Has a shape specific to the shape of the antigen

Question 2

Constant region

Answer 2

The region is the same in all antibodies

Question 3

Hinge region

Answer 3

Allows flexibility so that the molecule can grip more than one antigen

Question 4

Disulphide bridges

Answer 4

To hold polypeptides together.

Question 5

Opsonin:

Answer 5

A group of antibodies that bind to antigens on pathogens.

They act as binding sites for phagocytic cells so they can bind more easily and destroy pathogens.

Ones produced as part of specific immune response are specific to a particular antigen.

Question 6

Agglutinins:

Answer 6

An antibody has two identical binding site.

It is able to cross link the two pathogens bound to the 2 binding sites together. This clumps then.

Question 7

How to agglutination work?

Answer 7

Pathogens are physically impeded from carrying out functions such as entering hosts cell.

Agglutinated pathogens are readily engulfed by phagocytosis.

Question 8

Anti-toxin antibodies

Answer 8

Some antibodies bind to the molecules released by pathogenic cells.
These may be toxic and action of antibody renders them harmless.