Immunity

Question 1

pathogen

Answer 1

disease killing bacteria

Question 2

What are pathogens known as

Answer 2

transmissible diseases as they are passed on from one host to another

Question 3

what are the different ways pathogens can be passed on from host to host

Answer 3

• Direct contact - the pathogen is passed directly from one host to another by transfer of body fluids such as blood or semen (eg HIV)
• Indirect contact - the pathogen leaves the host and is carried in some way to another, uninfected individual

Question 4

Active Immunity

Answer 4

Making antibodies and developing memory cells for future response to infection

Question 5

state two ways in which this active immune response happens

Answer 5

• The body has become infected with a pathogen and so the lymphocytes go through the process of making antibodies specific to that pathogen
• Vaccination

Question 6

How do lymphocytes work

Answer 6

they can ‘read’ the antigens on the surfaces of cells and recognise any that are foreign
They make antibodies which are a complementary shape to the antigens on the surface of the pathogenic cell

Question 7

Passive Immunity

Answer 7

fast-acting, short-term defence against a pathogen by antibodies acquired from another individual Eg: breast milk

Question 8

What is dairrheoa

Answer 8

Diarrhoea is the loss of watery faeces from the anus

Question 9

what happens when there’s too much dioreah

Answer 9

If severe and continues for a long time, can lead to death
Severe diarrhoea can cause the loss of significant amounts of water and ions from the body, causing the tissues and organs to stop working properly.

Question 10

how can dioreah be treated

Answer 10

oral rehydration therapy
This is a drink with a small amount of salt and sugar dissolved in it