GCSE Biology - infection and responses

Flashcards for key concepts and vocabulary from GCSE Biology: Organisation, covering diseases, pathogens, immune response, drug testing, and monoclonal antibodies.

Communicable diseases

Diseases caused by pathogens that can be spread from person to person or between animals and people.

Pathogens

Microorganisms that can cause disease, including bacteria, viruses, fungi, and protists.

Types of pathogens

The four main types are bacteria, viruses, fungi, and protists.

Bacterial disease process

Bacteria reproduce rapidly and produce toxins that damage cells and tissues.

Viral disease process

Viruses replicate inside cells, bursting them and causing damage.

Salmonella

A bacterial disease that causes food poisoning with symptoms like fever, cramps, vomiting, and diarrhoea.

Control of Salmonella

Vaccinating poultry, practicing good hygiene, and properly cooking food.

Gonorrhoea

A sexually transmitted bacterial disease that causes pain when urinating and yellow/green discharge, caused by Neisseria gonorrhoeae.

Treatment and prevention of Gonorrhoea

Treated with antibiotics; prevented by barrier methods like condoms.

Measles

A viral disease spread by droplets that causes fever and rash; can be fatal and is prevented by MMR vaccine.

HIV

A virus that attacks the immune system, causing flu-like symptoms initially, and can lead to AIDS if untreated.

Tobacco mosaic virus (TMV)

A plant virus affecting tomatoes and tobacco, causing mosaic patterns on leaves and reducing photosynthesis.

Malaria

A protist disease caused by a protist carried by mosquitoes, leading to fever and potentially fatal consequences.

Prevention of Malaria

Uses mosquito nets, insect repellent, removing standing water, and antimalarial drugs.

Non-specific defence systems

Include skin (barrier), nose (mucus and hairs), trachea and bronchi (cilia and mucus), and stomach (acid).

White blood cells

Cells that engulf pathogens, produce antibodies, and produce antitoxins.

Antigens

Proteins on pathogen surfaces that trigger an immune response.

Antibodies

Proteins produced by white blood cells that bind to specific antigens to destroy pathogens.

Antitoxins

Substances produced by white blood cells that neutralise toxins released by pathogens.

Vaccinations

Introduce dead or inactive pathogens to stimulate white blood cells to produce antibodies.

Advantages of vaccination

Controls disease and prevents epidemics.

Disadvantages of vaccination

Not always effective and possible side effects.

Role of antibiotics

Kill or inhibit bacteria without harming body cells; ineffective against viruses.

Antibiotic resistance

Occurs when bacteria mutate and survive antibiotics, leading to the spread of 'superbugs'.

Role of painkillers

Treat symptoms but do not kill pathogens.

Sources of traditional drugs

Traditionally sourced from plants (e.g., aspirin from willow) and microorganisms (e.g., penicillin from mould).

Stages of drug testing

1) Preclinical on cells and, 2) Animal trials- made the first stage 3) Drugs that have passed animal trails and used in clinical trials 4) Double blind and placebo trials

Double blind trials

Trials where neither patient nor doctor knows who receives the real drug or placebo to prevent bias.

Monoclonal antibodies

Identical antibodies produced from a single clone of white blood cells that bind to one specific antigen.

Production of monoclonal antibodies

Mouse lymphocytes are fused with tumour cells to form hybridomas, which divide and produce antibodies.

Uses of monoclonal antibodies

Used in pregnancy tests, detecting disease, delivering drugs to cancer cells, and measuring hormone levels.

Advantages of monoclonal antibodies

Specific to targets.

Disadvantages of monoclonal antibodies

Can have side effects and pose ethical issues in testing.