Antibiotics and bacteria

Question 1

What is an antibiotic

Answer 1

Antibiotics kill bacteria by affecting things specific to bacterial cells and leaving human cells alone

Question 2

How does antibiotics affect bacterial cells

Answer 2

1. Disrupt the cell wall formation by inhibiting an enzyme- the bacterial cell bursts as they absorb water doe to the osmotic pressure and weakened cell walls
2. In hibit metabolic processes- eg protein synthesis- erythromycin destroys ribosomes in prokaryotic cells- doesnt affect larger ribsomes therefore only disrupts protein synthesis in bacterial cells and not the person

Question 3

Why are bacteria antiobiotic resistant when one or more antibiotic no longer has an effect

Answer 3

-Mutations in the bacterial genome result in metabolic changes preventing antibiotic from being effective
-Alleles that confer resistance are found on plasmids

Question 4

What are the benefits of new antibiotics

Answer 4

-More effective treatment
-Less treatment costs
-Less time off work ill
-Less death

Question 5

What are animal resevoirs

Answer 5

Animals that harbour viruses that cause death in humans
-resevoir species often suffer little harm from the virus- carry virus but not become infected
-not vectors- not adapted to transfer pathogen

Question 6

Explain bats as resevoirs

Answer 6

-Cause Marburg, SARS
-initial resevoir for rabies before transferred into dogs and humans

Question 7

Why are bats suitable resevoirs

Answer 7

-mammals with similar physiology
-social animals resulting in contact with large numbers of other bats thereby increasing possibility of cross infection
-fly large ranges and potentially in contact with other organisms