1.8 Changing Pathogens

Question 1

How doses natural selection cause resistant populations of bacteria to develop?

Answer 1

Some bacteria have developed resistance to antibiotics by natural selection

Question 2

Define epidemic

Answer 2

When more cases of an infectious disease are recorded than would normally be expected

Question 3

Define pandemic

Answer 3

When more cases of a disease ads recorded than normal in a number of different countries

Question 4

Define MRSA

Answer 4

Methicillin- resistant Staphylococcus aureus. An antibiotic resistant bacterium

Question 5

Why do some pathogens spread rapidly?

Answer 5

If a pathogen changes by mutation the new strain may spread rapidly

Question 6

Define natural selection

Answer 6

The process by which evolution takes place. Organisms produce more offspring that the environment can support so only those which are most suited to their environment- the ‘fittest’ will survive to breed and pass on their useful characteristics