If they can mate and produce fertile young
Genes and environment
Fossils and the similarities between living things
Selecting which pigs (for example) to breed because they produce the right meat
Survival of the fittest (and passing on your genes
If animals compete with each other only the most successful will survive to pass on their genes
Because people believed that the Bible was factually true
A sudden random change in the genes
Very simple – molecules that could copy themselves
Different cells do different jobs but they need to be able to communicate
Hormones and nervous system
Humans have not evolved from chimps but we have both evolved from something else
Between 1.5 and 4 million years ago – it walked upright
By destroying or disrupting natural environments or food supplies
To make protein
To replace nitrogen and other minerals needed for growth
Intensive – lots of fertiliser and pesticides Organic – none of the above
Chemicals used to kill animals and diseases that damage the crops
Natural predators like ladybirds
A process is sustainable if it can continue without harming the earth.
Preservatives – stop it going off Colours – make it look nice Flavourings – make it taste nice Emulsifiers & stabilisers – stop it separating
Carbohydrates – for energy Proteins – for growth and repair Vitamins & minerals – to keep healthy Fats – store energy
So they can be dissolved and absorbed into the blood
When someone has a reaction to a particular food eg peanuts.
Broken down into urea
Urea and excess water is removed and stored in the bladder
Type 1 In younger people – controlled by insulin Type 2 In older people – controlled by diet, medicine and sometimes insulin
Being overweight or obesity
Food standards agency – encourage people to eat healthily by promoting labelling and good practice
Produce ionising radiation which can damage living tissues
Alpha beta gamma
Alpha – low penetration – high ionisation Gamma – high penetration – low ionisation
Irradiation – radiation goes through it Contamination – contains something that is making radiation
Time, how close you are (proximity) and type of radiation
Breaks molecules like DNA and can lead to cancer
Small dense nucleus (protons & neutrons) surrounded by cloud of electrons
Atoms that have a different number of neutrons than normal – often radioactive
The time taken for the radioactivity to drop to half its value
Medical imaging, sterilising, treating cancer
LLW/ILW/HLW – High/intermediate/low It is sealed in glass or concrete and buried
Splitting heavy elements like uranium to release heat energy
Heat released 2. Water boiled 3. Steam turns turbines 4. Generator turned
It will never run out and the environment will not be ruined
Better safe than sorry
Don’t produce CO2
Don’t produce radioactive waste
Produced by radioactive rocks – we should keep our houses well ventilated