1. Biology for You © Nelson Thornes Ltd 2004 Populations 1 competition predators disease grazers human impact temperature light water oxygen Abiotic or environmental factors: Biotic factors caused by other living things:

2. Biology for You © Nelson Thornes Ltd 2004 A population is a group of individuals of the same 1……….. living in the same 2………... We need to study how populations grow to understand: the impact of 3…………. human population increase diseases like 4……………. Populations 2 x y z y 5…………..population growth z equilibrium population 6………. The limit might be reached because of lack of 7………, 8…………….., or the build up of toxic 9……………….

3. Biology for You © Nelson Thornes Ltd 2004 A population is a group of individuals of the same species living in the same habitat. We need to study how populations grow to understand: the impact of pests human population increase diseases like malaria. Populations 2 x y z y exponentialpopulation growth z equilibriumpopulation limit The limit might be reached because of lack of food, overcrowding, or the build up of toxic waste.

4. Biology for You © Nelson Thornes Ltd 2004 Populations 3 food and water oxygen toxic waste overcrowding disease climate lack of shelter Checks on population increase

5. Biology for You © Nelson Thornes Ltd 2004 Populations 4 Population size population size birth +death - emigration - immigration +

6. Biology for You © Nelson Thornes Ltd 2004 Adaptations hunt seals under water Why do polar bears have greasy fur? polar bear heat lost more rapidly Why is there no layer of fat under the skin? camel hibernates…………… during winterdormouse streamlinedflat and ………………mayfly nymph closeable to ……….. trap doorperiwinkle flatleaves grow ……………plantain migrate…………………. in winterswallows waterlarge stems, store ………cactus

7. Biology for You © Nelson Thornes Ltd 2004 Competition Species may compete for: There are two types of competition: competition 7………… species competition 8…………… a species. 1………….. 2 ………… 3 ………….. 4 …………. 5 ………… 6 ………….. Pests are excellent competitors: aphids and cockroaches compete with humans for 9……. weeds compete with other 10………… for space to grow.

8. Biology for You © Nelson Thornes Ltd 2004 Competition Species may compete for: There are two types of competition: competition between species competition within a species. food light water nutrients space nest sites Pests are excellent competitors: aphids and cockroaches compete with humans for food weeds compete with other plants for space to grow.

9. Biology for You © Nelson Thornes Ltd 2004 Predation time numbers

10. Biology for You © Nelson Thornes Ltd 2004 Predation time numbers

11. Biology for You © Nelson Thornes Ltd 2004 There is a 1………. increase in human population. There are fewer 2………. on human population: agriculture is 3………… there is improved public 4………….. there is 5………. disease people are living 6…………….. In developed counties there is a 7………… proportion of older people. Various methods of 8…………. control are needed but it can be a 9……………….. subject. Human populations

12. Biology for You © Nelson Thornes Ltd 2004 There is a rapid increase in human population. There are fewer checks on human population: agriculture is improved there is improved public health there is less disease people are living longer. In developed counties there is a higher proportion of older people. Various methods of birth control are needed but it can be a controversial subject. Human populations

13. Biology for You © Nelson Thornes Ltd 2004 The world human population is rising, leading to environmental problems. 1………………. results from a higher demand for tree products: Deforestation contributes to 6……… warming by reducing the amount of 7……… removed from the air. Destruction of rainforest leads to more species 8………………. Solutions include: Human impact  2…..  3…  4………  5……..  9…….  10……………  11………………………

14. Biology for You © Nelson Thornes Ltd 2004 The world human population is rising leading to environmental problems. Deforestation results from a higher demand for tree products. Deforestation contributes to global warming by reducing the amount of CO2 removed from the air. Destruction of rainforest leads to more species extinction. Solutions include: Human impact  paper  fuel  agriculture  construction  recycling  reforestation  sustainable management

15. Biology for You © Nelson Thornes Ltd 2004 Air pollution holes in the ozone layer acid rain global warming pollution problem skin cancerCFCs lakes, trees, crops, buildings damaged sulphur dioxide climate change carbon dioxide resultgas

16. Biology for You © Nelson Thornes Ltd 2004 Water pollution oil spills eutrophication raw sewage release pollution problem damage to marine environment oil lack of oxygen fertiliser run-off lack of oxygensewage resultsubstance

17. Biology for You © Nelson Thornes Ltd 2004 The aim of conservation is to increase 1…………..: protecting 2……………… species from human impact captive 3………… programmes to rescue rare species seed 4…… to ensure survival of a wide range of plants 5…………… parks covering large areas like Snowdonia national nature 6…………. preserve the biodiversity of native species 7……… of ………… ……….. …………. (SSSIs) conserve rare or endangered species. Conservation

18. Biology for You © Nelson Thornes Ltd 2004 The aim of conservation is to increase biodiversity: protecting endangered species from human impact captive breeding programmes to rescue rare species seed banks to ensure survival of a wide range of plants national parks covering large areas like Snowdonia national nature reserves preserve the biodiversity of native species Sites of Special Scientific Interest (SSSIs) conserve rare or endangered species. Conservation

19. Biology for You © Nelson Thornes Ltd 2004 Wastes like crude oil and plastics are 1……. to break down. Crude 2…. spills kill wildlife. Microbes will 3……… break the oil down. It is better to 4…….. oil spills. Plastics are bad 5…………… because they are so hard for microbes to break down. However, plastics are now being made that can be 6……………… down by microbes in the soil. More and more supermarket carrier bags and rubbish sacks are being made from 7………………plastics. Biodegradation biodegradable7 broken6 pollutants5 prevent4 slowly3 oil2 difficult1