Unit 4 - Specific immune response Flashcards Preview

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Flashcards in Unit 4 - Specific immune response Deck (27)
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1
Q

What are antibodies?

A

Y-shaped glycoproteins made by B cells of the immune system in response to the presence of an antigen

2
Q

What is a specific immune response?

A

The immune system ‘remembers’ an antigen after an initial response leading to an enhanced response to subsequent encounters

3
Q

What shape are antibodies?

A

Y-shaped

4
Q

Where do T-cells mature?

A

Thymus gland

5
Q

Where do B-cells mature?

A

Bone marrow

6
Q

What is the function of B plasma cells?

A

To produce antibodies

7
Q

How does the sequence of amino acids affect an antibody?

A

The sequence of amino acids determines the shape of the variable region (sequence of amino acids) and so which antigen is detected

8
Q

How many polypeptide chains does an antibody contain?

A

4

9
Q

What type of molecule is an antibody?

A

Protein

10
Q

What is the relationship between the two light chains of antibodies?

A

They are identical

11
Q

What is the relationship between the two heavy chains of antibodies?

A

They are identical

12
Q

What sort of protein are antibodies?

A

Globular

13
Q

How many binding sites are there on an antibody?

Where are they?

A

3
Two antigen binding sites
One receptor site that allows the body to recognise the antibody as self

14
Q

How are all antibodies in the body similar?

A

They share the same common region

15
Q

What type of bonding occurs between the heavy and light strands in antibodies?

A

Disulfide

16
Q

How are the heavy strands attached in antibodies?

A

Disulfide bonds

17
Q

How many light strands are in an antibody?

A

2

18
Q

How many heavy strands are in an antibody?

A

2

19
Q

What is the relationship between the variable region and the antigen?

A

They have complementary shapes

20
Q

What allows for sulfide bonding?

A

The amino acid cysteine

21
Q

Why do antibodies have a hinge?

A

Allows antibodies to flex slightly and accommodate differently sized antigens

22
Q

What is the difference between the light and heavy chains of an antibody?

A

The light chains are much shorter than the heavy chains

23
Q

How many amino acids form a binding site?

A

110

24
Q

What is formed when an antibody binds to an antigen?

A

An antigen-antibody complex

25
Q

How do antibodies defend the body? (4 reasons)

A
  • 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
26
Q

Name the 4 types of T cells

A
  • Killer T cells
  • Helper T cells
  • Memory T cells
  • Regulator T cells
27
Q

Name the 3 types of B cells

A
  • B Plasma cells
  • B effector cells
  • B memory cells