GCSE Biology – Immunity, Drugs and Vaccines

Infection and immunity are topics which many students find difficult when studying for the GCSE Biology exams, especially as subtopics such as monoclonal antibodies have now dropped down from the A Level course. From learning how to treat certain diseases with drugs you will also need to know how vaccines help to prevent them. You will need to know the difference between bacterial and viral infections and how they can be treated. You will also look at how the human immune system prevents entry of pathogens ad how it responds to infection.

Immunity, Drugs and Vaccines Revision

What is a pathogen?

– It is a microorganism that causes disease.

Are bacteria and viruses different?

– Yes very different. Bacteria are much larger and are a living cells where as a virus is an infectious particle. Bacteria can be treated using antibiotics but viruses can’t.

Are placebos just fake drugs?

– A placebo is something which is given as a drug but has no active ingredients. The placebo effect is real and can help people’s symptoms to improve, but we aren’t too sure why. We use placebos in drug trials to see how effective new drugs are.

How do white blood cells work?

– They recognise pathogens as foreign and engulf them. They also produce antibodies which causes the pathogens to stick together so more of them can be engulfed.

How do we prevent pathogens from entering our body?

– Mucous in our nose and throat, skin and our stomach acid.

What is a monoclonal antibody?

– It is an antibody that has been produced from one specific type of white blood cell. Every antibody produced by this white blood cell will be the same and therefore monoclonal.

How do vaccines work?

– Vaccines contain and a dead or inactive form of a pathogen that causes an immune response resulting in the production of memory cells. The next time the liv pathogen enters the body, the white blood cells produce the specific antibodies which then destroy it.