GCSE Biology- bacteria and disease

How can pathogens be spread?

Touch, coughs, sneezes, bodily fluids

Types of pathogens

Bacteria, virus, fungi and protist

Ways of stopping the spread of pathogens

Hand washing, vaccination, destroying vectors

What do bacteria produce

Toxins

What is tobacco mosaic disease

Virus
Happens in plants
To stop: remove decaying leaves from plants on and around it
Treatment: sanitation
Symptoms: light green coloration on veine of leaves, patten of light and dark green areas

What is salmonella?

Bacteria
Eating uncooked/ poisoned food
To stop: cook food properly, keep food refrigerated properly
Treatment: loperamide, anti- diarrheals
Symptoms: cramps, throwing up, head ache

What are measles?

Virus
To stop: have vaccine
Treatment: lots of water, pain killers, rest to boost immune system
Symptoms: cough, fever, light sensitivity, white spots inside of mouth

What is gonorrhea?

Bacteria
To stop: use contraception
Treatment: antibiotics
Symptoms: irregular menstruel bleeding, painful urination, general tiredness

What is HIV

Virus
To stop: use contraception, tell partner, drugs
Treatment: antiretroviral therapy and medication
Symptoms: body rash, fever, swollen glands
Lasts 1-2 weeks

What is a placebo

A drug used for a psychological benefit rather than physical

What is a double blind trial?

An experiment where the participent is unaware of any information of the drug. These are used to prevent the outcomes from being influenced.

What is herd immunity?

Resistance to the spread of a contagious disease which causes a large amount of people to become immune ( vaccine )

How to viruses reproduce?

Inside cells which means it's hard to kill them without damaging the body tissue

Good medicine is...

Effective, safe, stable, successfully taken into and out of the body

What was thalidomide originally used for?

Pregnant woman to stop morning sickness, however this caused deformed children as it was not tested on an unborn children. They eventually found others uses for it such as certain types of cancer and auto-immunes disease.

White blood cells when fighting disease

Engulf phagocytosis, antibody production and antitoxin production

What is rose black spot?

It is caused by diplocarpon rosae is a fungus which cause rose black spots. It can be treated with fungicide. It can be spread from plant to plant on hands, clothing and tools.

What is malaria?

A parasite carried by mosquitoes, spread when a person gets bit, called plasmodium parasite. Ways to stop the spread is mosquito repellent, long sleeves, bed nets.

Natural body defences against infection

Natural barriers such as skin, mucus and stomach acid. Urine wipes out any microorganisms that enter the urging tract.

What are white blood cells?

Cells in the immune system which protect the body against infection and disease

Process of vaccination

It is where a small amount of an inactive pathogen is put into the body. It includes live pathogens, harmless fragments of the pathogen, toxins produced by the pathogen and dead pathogens. These act as antigens which stimulate white blood cells to produce antibodies to fight the pathogen.

What do antibiotics treat?

Bacterial infections

What is antibiotic resistance?

A consequence of evolution from natural selection. Those bacteria with the mutation reproduce and allow their offspring to also be resistant. This causes a fully resistant generation.

What are painkillers?

Powerful drugs which interfere with the nervous system's transmission of the nerve signals which we know as pain. Some also stimulate the brain with pleasure.

How were drugs originally made?

They were extracted from plants and microorganisms.

Who discovered penicillin and from what?

Alexander Fleming. It is made from a type of Penicillum and is produced when the fungus is inhibited by stress

How are most drugs made?

They are synethised by chemists in the pharmaceutical industry however the starting chemicals may be extracted from plants

Clinical trail phases

Phase 0- first in human trail, given to 10-15 subjects
Phase 1- given to a small amount of healthy people
Phase 2- performed are larger groups, which help to establish therapeutic doses
Phase 3- drug is given over 6-12 months in a large patient population (several hundred)
Phase 4- post marketing which include safety surveillance and ongoing technical support.

What is the preclinical phases

The drugs are tested using computer models and human cells in a laboratory to see if cells get damaged.
They are then tested on animals
Then healthy volunteers