BIOLOGY medicine and disease

what are pathogens?

microorganisms that cause disease

what is a microorganism?

an organism that is too small to be seen with the naked eye

what are communicable diseases?

diseases caused by pathogens that are passed from one person to another

what are non-communicable diseases?

diseases that cannot be passed from one person to another

apart from disease, what three factors can affect health?

lifestyle, life experience and genetic disposition

where do bacteria and viruses reproduce?

inside your body

where in your body do viruses live and reproduce?

inside your cells

name three viral diseases

AIDS/HIV, measles, tobacco mosaic virus

what are the initial symptoms of HIV?

a flu-like illness

what part of the body does HIV affect?

the immune system

how is HIV spread?

by sexual contact or exchange of body fluids

how is HIV prevented?

using condoms, not sharing needles

why do bacteria make you feel ill?

they produce toxins

what is a toxin?

a poison

name two bacterial diseases

salmonella, gonorrhea

what type of disease does salmonella cause?

food poisoning

what are the symptoms of salmonella food poisoning?

fever, abdominal cramps, vomiting and diarrhoea

how is salmonella food poisoning prevented?

cooking chicken well, and by vaccinating chickens

what is a fungus?

an organism made of cells which are neither animal nor plant cells

name a fungal disease

rose black spot

what are the symptoms of rose black spot?

purple or black spots on the leaves, which turn yellow and fall off early

how is rose black spot spread?

by water or wind

how is rose black spot prevented?

use a fungicide or remove the infected leaves

what are protists?

a type of single celled organism

what diseases do protists cause?

malaria

what does malaria cause?

reoccurring episodes of fever and death

what is a vector?

an animal that can carry a pathogen between infected individuals

what are the vectors involved in spreading malaria?

mosquitos

how is the spread of malaria controlled?

by preventing mosquitos from breeding and by using mosquito nets to avoid being bitten

what are painkillers?

medicines that stop the pain from diseases

give examples of painkillers

aspirin and paracetamol

what are antibiotics?

medicines that kill bacteria

how do antibiotics kill bacteria?

damage the bacterial cell without harming human cells

give an example of an antibiotic

penicillin

can antibiotics kill viruses?

no

where were drugs traditionally extracted from?

from plants and microorganisms such as moulds

who discovered penicillin?

Alexander Fleming

what is the source of the antibiotic penicillin?

penicillin mould

how are new drugs made?

synthesised by chemists from a extracts from a plant or microorganism

give two benfits of using synthetic forms of drugs rather than plant extracts

can be mass-produced; easily modified

what drug is extracted from the foxglove plant?

digitalis

what is digitalis used for?

strengthen heart beat

why do new medical treatments need to be extensively tested and trialled?

to ensure the treatment works well and is safe

what 4 factors make a good medicine?

effective, safe, stable and easily removed from the body

what 3 things are new medical drugs tested for?

efficacy, toxicity and dosage

what is efficacy?

how well a medicine works

what is preclinical testing?

testing in a lab

what three things can preclinical tests be carried out on?

cells, tissues, live animals

what are clinical trials?

tests using healthy volunteers and patients

what is a placebo?

a substance that does not contain the drug

what are double blind trials?

when neither the doctor nor patients know who has received the real drug or the placebo