2. B1b.4.1 TB in London
• tubercolosis [TB] is a disease caused by
bacteria
• TB bacteria are mycobacteria
• mycobacteria can be dormant in the body for
years
• TB is spread through air
3. • AIDS is caused by the HIV virus
• AIDS destroys the body’s immune system
• c. 50% of AIDS sufferers will get TB
4. B1b.4.2 Controlling tuberculosis
• drugs are substances which change the way
the body works
• antibiotics are drugs that kill bacteria
• bacteria develop resistance to antibiotics
• new drugs are tested for years before being
approved for trials on humans
• BCG is the vaccine against TB
5. B1b.4.3 Microorganisms and disease
• a pathogen is a microorganism that causes
disease
• transmission
of pathogens…
10. B1b.4.6 The third line of defence
• specific immune system activated when first
two lines of defence fail
• white blood cells produce antibodies
• antibodies fight pathogens…
11. • immunisation involves injecting a harmless
amount of infection into body
• specific immune system produces antibodies
so is ready for a real attack
12. B1b.4.7 Types of drugs
• Stimulants improve alertness and reaction times
by increasing rate of diffusion across synapses,
e.g. caffeine, amphetamine, cocaine. Addictive.
• sedatives slow down the rate of diffusion across
synapses, e.g. alcohol, barbiturates. Addictive
and can cause tolerance [bigger doses needed].
• painkillers [or analgesics], e.g. aspirin,
paracetamol [Panadol™], ibuprofen, heroin,
morphine. Block diffusion across synapses. Some
are addictive.
13. B1b.4.8 Pain relief
• overdose means taking more than stated amount of a
drug
• a paracetamol overdose can severely damage the liver
• opiates [morphine and heroin] are addictive and
create tolerance
• tolerance can lead to an overdose
• heroin is usually injected risking transmission of
pathogens, e.g. HIV and hepatitis B
• canabis can cause psychosis as well as bronchitis and
lung cancer
14. B1b.4.9 Drug misuse and abuse
• solvents are sedatives
• solvent abuse can cause instant death by heart
attack or suffocating if a plastic bag is used
• solvents can damage the myelin sheath of
neurones so that impulses are no longer carried
• Alcohol is a sedative. Can be addictive and
creates tolerance. Heavy drinking causes brain
and liver damage.
15. B1b.4.10 Tobacco
• tobacco has serious effects on breathing and
circulatory systems
• tobacco contains nicotine
• nicotine is a very addictive stimulant
• tabacco smoke contains carcinogens and carbon
monoxide and causes emphysema
• carbon monoxide binds to haemoglobin and
reduces red blood cells ability to carry oxygen
• nicotine and carbon monoxide together increase
blood clotting that can cause a heart attack
![B1b.4.1 TB in London
• tubercolosis [TB] is a disease caused by
bacteria
• TB bacteria are mycobacteria
• mycobacteria can be dormant in the body for
years
• TB is spread through air](data:image/gif;base64,R0lGODlhAQABAIAAAAAAAP///yH5BAEAAAAALAAAAAABAAEAAAIBRAA7)