Edexcel Biology 2105, also Science 2101, Additional Science 2103

Unit B1 b

Topic 4 - Use, Misuse and Abuse

Young people in Britain are offered the opportunity of a ‘BCG’ vaccination to protect them from Tuberculosis (TB). The body can be attacked and disrupted by the actions of disease-causing organisms (pathogens), such as the bacteria that cause TB. The body has three lines of defence against pathogens - physical, non-specific mechanisms and the immune system. Natural defences can be assisted with drugs. Some drugs affect the pathogen, others change the reactions of the body. Some drugs may be misused to alter the state of mind or body.
This topic will look particularly at the use of pain-relieving drugs and the difficulties associated with them. There are opportunities to interpret data on the effectiveness of different drugs. Students can present information and develop arguments on the use of drugs in a range of contexts. They can also collect and interpret data from secondary sources and discuss the social, economic and ethical implications of drug misuse and abuse.

Guidance for students

Have you ever wondered?
Are there more ‘good’ microorganisms than disease-causing ones?
What is the difference between an infection and a disease?
Why is TB in the news again?
Why won’t your doctor give you antibiotics for a cold?
Why it is so expensive to produce a new drug?
Why are the uses of some substances controlled by law?
Why are some drugs considered good for your body and others bad?
How do different drugs affect people differently?
Learning objectives
• The human body has three lines of defence against invading microorganisms.
• Immunisation and antibiotics are used against diseases caused by microorganisms.
• The use and misuse of substances can affect the normal functioning of the body systems,
affecting mental and physical health.
• There are socio-economic reasons that contribute to ill health and ethical considerations for the
development of treatments.

Glossary
You will be expected to be able to recall, explain, describe and use appropriately the following words and phrases:

addiction	circulatory system	microorganism	solvent
alcohol	disease	neurone	stimulant
antibody	drug	opiate	tobacco
antigen	foreign body	organism	transmission
bacteria	gaseous exchange	overdose	tuberculosis
barbiturate	immune system	pain-relief	vector-borne
barrier	infection	paracetamol	viral infection
caffeine	inflammation	pathogen	white blood cell
cannabis	lysozyme	reaction time
cilia	microbe	sedative
depressants	synapse

Information for teachers
ICT is an integral part of the way science works, and students should be given opportunities to experience and explore its use. It is expected that ICT will be used where it enhances the learning and teaching of science and helps to make scientific concepts easier to understand.
Some of the learning outcomes have been written deliberately in order to promote discussion and expression of opinion. Where contentious, unresolved or other scientific issues are discussed, it is expected that students will be exposed to the facts, evidence and opinions from all sides of the argument.
Learning outcomes
Learning outcomes, words or statements in bold indicate that this content is designated for Higher tier students only.
Students will be assessed on their ability to:

• describe the main physical and mental effects of: . solvents (on lungs and neurones) . alcohol (on reaction times, liver and brain) . tobacco (on gaseous exchange and circulatory systems)	B1 b 4.1
• describe how the use of drugs may: . affect activities such as driving . produce abnormal behaviour . create the risk of viral infections	B1 b 4.2
• explain the effects on nerve transmission (including synapses) on reaction times of: - stimulants, including caffeine - sedatives, including barbiturates - painkillers, including paracetamol - depressants, including alcohol and solvent	B1 b 4.3
• discuss the use of opiates and cannabinoids in pain-relief for terminally-ill patients, and the dangers of addiction.	B1 b 4.4
• describe the uses of paracetamol and the dangers of overdose	B1 b 4.5
• discuss why medical opinion on the use of cannabis for pain-relief has fluctuated over the years	B1 b 4.6
• describe a pathogen as a disease-causing organism	B1 b 4.7
• explore, using secondary data, the main physical and mental effects of the misuse of drugs and their impact on behaviour	B1 b 4.8
• explain that microbes can be transmitted by direct contact, including vertical (mother to foetus) and horizontal, indirect contact, vehicle and vector-borne	B1 b 4.9
• describe the physical barriers as the body’s first line of defence against microorganisms, including the role of the skin, nasal hairs and cilia in the gaseous exchange tract and chemical barriers, namely lysozyme, found in tears	B1 b 4.10
• describe the second line of defence against infection as non-specific: . white blood cells ingest bacteria . inflammatory response	B1 b 4.11
• describe the third line of defence as the specific immune system - when the immune system recognises a foreign body (antigen) and prepares a specific reaction to it (antibody production by white blood cells)	B1 b 4.12
• explain what causes tuberculosis (TB) and how it is spread	B1 b 4.13
• describe, using secondary data, the prevention and control (drug therapy) of TB including the emergence of drug-resistant TB, financing, supply of drugs and treatment regimes	B1 b 4.14
• interpret data on the number of cases of TB in the UK over a period of time	B1 b 4.15
• use secondary data to explore the costs of developing new drugs.	B1 b 4.16
REMOVED [• explore secondary sources of data about the main physical and mental effects of the misuse of drugs and present the data in different ways to different audiences using ICT]	[WAS B1 b 4.15]