drugs

Question 1

definition of drug

Answer 1

any substance when taken into the body modifies or affects the chemical reactions in the body

Question 2

Antibiotics

Answer 2

drug that only targets bacteria cells

antibiotics target bacteria-specific mechanisms so eukaryotic cells are not affected

Question 3

4 mechanism of antibiotics

Answer 3

1.inhibit cell wall synthesis
penicillin prevents formation of cell wall,when bacteria has no cell wall,water can enter via osmosis and cell will swell and burst(lyse)
2.inhibit protein synthesis
-antibiotics(tetracycline) bind to bacterial ribosomes and prevent them from synthesising any proteins-bacteria have no enzymes to function
3inhibit enzyme action
-bacteria require folic acid to grow->sulfa antibiotics inhibit the enzymes required for folic acid production so bacteria cant grow
4.inhibit cell membrane
-some antibiotics(polymyxin) act by breaking up cell membrane

Question 4

why antibiotics dont work on viruses

Answer 4

no metabolism,no cell wall only protein coat, no cell membrane so nothing antibiotics could target

Question 5

why bacteria develop antiobiotic resistance

Answer 5

short generation time-reproduce in 20-30min

widespread use of antibiotics
not finishing course of antibiotics-some bacteria may survive and develop partial or complete resistance
antibiotic resistance genes coated in plasmids,which are easily transferable between bacteria