Specific immune response Flashcards
What are antibodies?
Y-shaped glycoproteins made by B cells of the immune system in response to the presence of an antigen
What is a specific immune response?
The immune system ‘remembers’ an antigen after an initial response leading to an enhanced response to subsequent encounters
What shape are antibodies?
Y-shaped
Where do T-cells mature?
Thymus gland
Where do B-cells mature?
Bone marrow
What is the function of B plasma cells?
To produce antibodies
How does the sequence of amino acids affect an antibody?
The sequence of amino acids determines the shape of the variable region (sequence of amino acids) and so which antigen is detected
How many polypeptide chains does an antibody contain?
4
What type of molecule is an antibody?
Protein
What is the relationship between the two light chains of antibodies?
They are identical
What is the relationship between the two heavy chains of antibodies?
They are identical
What sort of protein are antibodies?
Globular
How many binding sites are there on an antibody?
Where are they?
3
Two antigen binding sites
One receptor site that allows the body to recognise the antibody as self
How are all antibodies in the body similar?
They share the same common region
What type of bonding occurs between the heavy and light strands in antibodies?
Disulfide
How are the heavy strands attached in antibodies?
Disulfide bonds
How many light strands are in an antibody?
2
How many heavy strands are in an antibody?
2
What is the relationship between the variable region and the antigen?
They have complementary shapes
What allows for sulfide bonding?
The amino acid cysteine
Why do antibodies have a hinge?
Allows antibodies to flex slightly and accommodate differently sized antigens
What is the difference between the light and heavy chains of an antibody?
The light chains are much shorter than the heavy chains
How many amino acids form a binding site?
110
What is formed when an antibody binds to an antigen?
An antigen-antibody complex
How do antibodies defend the body? (4 reasons)
- Act as opsonins so the antigen is ‘tagged’ and easily engulfed
- Act as antitoxins, binding to toxins produced by pathogens to render them harmless
- Cause agglutination (clumping together) of pathogens which have antigen-antibody complexes, preventing them from spreading through the body and makes it easier for phagocytes to engulf several pathogens at once
- Prevents pathogens from effectively invading a host
Name the 4 types of T cells
- Killer T cells
- Helper T cells
- Memory T cells
- Regulator T cells
Name the 3 types of B cells
- B Plasma cells
- B effector cells
- B memory cells
