Biology Paper 1 - Cell Recognition And The Immune System

Front 1

Specific Defence Mechanism

Back 1

Response is slower and is specific to each pathogen

Cell mediated response - T lymphocytes

Humoral response - B lymphocytes

Front 2

Non Specific Defence Mechanism

Back 2

Physical barrier

Phagocytosis

Response is immediate and is the same for all pathogens.

Front 3

Apoptosis

Back 3

Cell death

Front 4

Pathogen

Back 4

Something that can cause disease

Front 5

Phagocytes

Back 5

A type of white blood cell that carries out phagocytosis

Front 6

Antigen

Back 6

Any part of an organism or substance that is recognised as non-self by the immune system and stimulates an immune response

Front 7

B Lymphocytes

Back 7

Specific immune response

Bone marrow

Humoral immunity

Front 8

T Lymphocytes

Back 8

Specific response

Thymus gland

Cell mediated immunity

Front 9

Antigen presenting cells

Back 9

Cells that display foreign antigens on their surface

Front 10

Cell mediated immunity

Back 10

Will respond to antigens that are presented on a body cell rather than in body fluids.

Respond to organisms own cells that have been infected by non self material from different species.

Front 11

Cytotoxic T Cells

Back 11

Kills abnormal cells and body cells that are infected by pathogens, producing a protein called performing which makes tiny holes in the cell surface membrane.

Front 12

Humoral Immunity

Back 12

Involves antibodies which are soluble in blood and tissue fluid.

Produce specific antibodies to respond to specific antigens.

Front 13

Monoclonal Antibodies

Back 13

B cells that make clones which produces one specific antibody

Front 14

Plasma Cells

Back 14

Primary immune response

Immediate defence of the body against infection

Front 15

Memory Cells

Back 15

Secondary immune response

Front 16

Antibodies

Back 16

Are proteins with specific binding sites synthesised by B cells.

These react to antigens on the surface of the non self material by binding to them.

Front 17

Uses for Antibodies

Back 17

• Targeting medication to specific cell types

(E.g.) cancer - block chemical signals that stimulate uncontrolled cell growth

• Medical Diagnosis

Faster method of diagnosing

• Pregnancy Testing

Urine binds to the antibodies on the test

Front 18

What are the ethical issues of antibodies?

Back 18

• Animal testing for production

• Patients must have knowledge on the risk and benefits

• Testing for the safety of drugs can be dangerous

Front 19

Passive Immunity

Back 19

Introduction of antibodies into individuals from an outside source

Immunity acquired immediately

No memory cells produced, no lasting immunity

Front 20

Active Immunity

Back 20

Stimulating the production of antibodies by the individuals own immune system

• Natural Active Immunity

• Artificial Active Immunity

Vaccination

Front 21

Features of a successful vaccination

Back 21

• Economically available

• Few side effects

• Vaccinate the vast majority of people

Front 22

Herd Immunity

Back 22

When a large proportion of the population has been vaccinated to amke it difficult for the pathogen to spread within the population.

Front 23

Why may vaccination not be successful?

Back 23

• Defective immune systems

• Pathogen may mutate frequently

• Impossible to devolope a vaccine for a variety of pathogens

• Individuals may object

Front 24

Ethical issues of vaccines

Back 24

• Animal testing

• Side effects

• Should vaccination be compulsory

Front 25

ELISA Test

Back 25

Uses antibodies to detect the presence of a protein in a sample but also its quantity.