- Created by: abbiedye
- Created on: 24-06-18 13:25
Why do organisms need to compete?
- Organisms need things from their environment and from other organisms in order to survive and reproduce
Plants - need light and space and mineral ions (nutrients)
Animals - need space, food, water and mates
How do environment changes effect organisms?
- each species depends on other species for things like food, shelter, pollination and seed dispersal
- if one is killed off or decreased, the rest of the chain is effected
What are abiotic factors?
- non-living factors
- moisture level
- light intensity
- carbon dioxide level (plants)
- wind intensity and direction
- oxygen level (aquatic)
- soil pH and mineral content
- change in environment could be an increase or decrease in an abiotic factor
What are biotic factors?
- living factors
- new predators
- new pathogens
- availability of food
- change in the environment could be the introduction of a new biotic factor (new predator/pathogen)
What are adaptations?
- Organisms, including microorganisms, are adapted to live in different conditions
- The features or characteristics that allow them to do this are called adaptations
What are structural adaptations?
- features of an organism's body structure - shape or colour
Arctic fox - camouflage - to avoid predators
Whales - thick layer of blubber and low surface area to volume ratio - to retain heat
Camels - then layer of fat and a large surface area to volume ratio - to lose heat
What are behavioural adaptations?
- ways that organisms behave
Many species (e.g. swallows) migrate to warmer climates during the winter to avoid the problems of living in cold conditions
What are functional adaptations?
- things that go on inside the body that can be related to processes like reproduction and metabolism
Desert animals - conserve water - sweat very little and small amounts of concentrated urine
Brown bears - hibernate - lower metabolism to conserve energy
Why do microorganisms adapt?
- Microorganisms have a huge variety of adaptations so that they can live in a wide range of environments
extreme conditions such as high temperatures, high salt concentrations and high pressures
What is a food chain?
PRODUCER -> PRIMARY CONSUMER -> SECONDARY CONSUMER
5000 DANDELIONS -> 100 RABBITS -> 1 FOX
each part of the food chain depend on each other
What is the water cycle?
- Water evaporates and transpirates - to make water vapour
- Warm water is carried upwards and condenses to form clouds
- It is then precipitated (rain) onto land and provides fresh water for plants and animals
- It then evaporates and transpirates again
What is the carbon cycle?
Carbon dioxide is absorbed into the air by fossil fuels, waste, decay, respiration and combustion
It is then absorbed back by trees using photosynthesis
What is biodiversity?
The variety of different species of organsims on Earth, or within an ecosystem
It is important fo the Earth's biodiversity to be high
How does population increases effect biodiversity?
The increasing population puts pressure on the environment
People are demanding a higher standard of livin - using raw resources
Waste products of reducing biodiversity
Water - sewage and toxic chemicals can pollute lakes, river and oceans, affecting organisms that rely on them
Land - we use toxic waste, bury nuclear waste and dump household waste - landfill
Air - smoke and acidic gases pollute the air - sulfur dioxide = acid rain
What is global warming?
Gases like carbon dioxide and methane trap energy from the sun in the earth's atmosphere, meaning it can't escape
Consequences of global warming
Seawater wil expand and ice will melt - sea level will rise
Distribution of many wild animals and plants may change - rainfall
Change in migration patterns
Biodiversity could be reduced if some species are unable to survive
What do humans use land for?
Building, quarrying, farming and dumping waste
Less land for other organisms
What is deforestation?
- cutting down of forests
- cuts down tropical areas
- clearing land for farming
- to grows crops for biof
What are the problems of deforestation?
- less carbon dioxide taken in
- more carbon dioxide in the atmosphere
- less biodiversity
Peat bogs carbon dioxide
- Bog are areas of land that are acidic and waterlogged. Plants that live in bogs don't fully decay - not enough exygen
- When peat is drained, it comes into contact with air and microorganisms decompose it. They use respiration and let out carbon dioxide.
Programs protecting ecosystems and biodiversity
- breeding programmes
- protect and regenerate rare habitats
- reintroduce hedgerows and field margins
- reducing deforestation
- reducing waste
Conflicting pressures of maintaining biodiversity
- costs money
- cost to local people's livelihood
- conflict between protecting biodiversity and food security
- development is important but can affect the environment