7.1+7.2- Adaptations, interdependence and competition AND organisation

what are the different levels of organisation in an ecosystem

1. species

2. habitat

3. population

4. community

5. ecosystems

what is a species

organisms that are able to interbreed and produce fertile offspring

what is a habitat

a place where an organism lives

what is a community

the population of different species living in a habitat

what is a population

all the members of the same species within the same habitat

what is an ecosystem

the interaction of the community of biotic organisms with the abiotic parts of their environment

what is interdependence

the network of relationships between different organisms within a community (depending on another species for food)

what is competition

when living organisms compete with each other for limited resources

what may animals compete for

• food

• light

• reproductive partners

• territory

what may plants compete for

• light

• space

• water

• mineral ions from soil

what is a stable community

one where all the species and environmental factors are in balance so that population sizes remain fairly constant

what is the food chain in order

1. producer

2. primary consumer

3. secondary consumer

4. tertiary consumer

what happens to the numbers of predators and prey in a stable community

they rise and fall

what is a producer

an organism like plants and algae that can make their own food from raw materials such as carbon dioxide and water

what is a primary consumer

animals that eat producers

what is a secondary consumer

an animal that eats primary consumers

what is a tertiary consumer

animals that eat the secondary consumers

what are predators

consumers that kill and eat other animals

what are prey

animals that are eaten

what are biotic factors

living components of an ecosystem

what are abiotic factors

non-living components of an ecosystem

what are some abiotic factors

• moisutre level

• light intensity

• temperature

• carbon dioxide level (for plants)

• wind intensity and direction

• oxygen level

• soil pH and mineral content

how can light intensity affect organisms

limits photosynthesis so affects the distribution of plants and animals, some have more chlorophyll or bigger leaves for low light levels

how can temperature affect organisms

limits photosynthesis and growth in plants, low temperatures means plants are small which affects the amount of herbivores that can survive

how can wind intensity and direction affect organisms

shape of trees and landscape affected, plants transpire fast

how can new pathogens or parasites affect organisms

organisms have no resistance to new disease so new pathogens can wipe out populations in a community

how does oxygen availability affect organisms

some invertibres can survive in low water oxygen levels

how can new predators affect organisms

organisms that have no defences against new predators can be quickly wiped out

how can availability of food affect organisms

with no supply of food animals struggle to survive and dont breed

how can soil pH and mineral content affect organisms

carnivorous plants survive in low nitrate levels most others require high nitrate and mineral ion levels

how can interspecific competition affect organisms

new species may outcompete another and make numbers too low for successful breeding

how can availability of carbon dioxide affect organisms

acts as a limiting factor for photosynthesis and growth, affects distribution of organisms

how can moisture levels affect organisms

less water so less life

what are some biotic factors

• new predators

• competition

• new pathogens

• availability of food

what type of adaptations may an animal have to enable it to survive in its conditions

• structural

• behavioural

• functional

what is an adaptation

a special feature that makes an organism particularly suited to the environment where it lives

what are extremophiles

organisms that live in very extreme environments, such as at high temperature, pressure, or salt concentration

what are used to determine the distribution and abundance of species in an ecosystem

• transects

• quadrats

what is a transect

a measured line or area along which ecological measurements are made

what is a quadrat

a sample area used for measuring the abundance and distribution of organisms in a field

what is an abundance

a measure of how common or rare a particular type of organism is in a given environment

what does the carbon cycle do

returns carbon from organisms to the atmosphere as carbon dioxide to be used by plants in photosynthesis.

what does the water cycle do

provides fresh water for plants and animals on land before draining into the seas. Water is continuously evaporated and precipitated.

the carbon cycle step-by-step

1. photosynthesis removes CO2 from the atmosphere

2. respiration returns some CO2 to the atmosphere

3. organic carbon compounds stored in plants are eaten by animals

4. organic carbon compounds found in dead animals

5. decomposition returns CO2 to atmosphere

6. fossil fuels used to contain carbon compounds in power stations

7. combustion releases CO2

what is the rate of decay affected by

• temperature

• water

• oxygen availability

how is biogas made

microorganisms that decay plant and animal waste anaerobically and produce methane

what is biogas made in

a simple fermenter called a digester or generator

why does biogas need to be used straight away

it needs too high a pressure to be stored as a liquid

what can biogas be used for

• heating

• cooking

• lighting

• to power a turbine to generate electricity

what Environmental changes affect the distribution of species in an ecosystem

• temperature

• availability of water

• composition of atmospheric gases

what may Environmental changes that affect the distribution of species in an ecosystem be due to

• seasonal

• geographic

• human interaction

how does temperature affect the rate of decay

warmer temperatures make things decompose quicker because they increase the rate that the enzymes work at but if its too hot the rate of decomposition slows down

how does water availability affect the rate of decay

decay is faster in moist environments because the organisms involved need water to carry out biological processes

how does oxygen availability affect the rate of decay

most organisms need oxygen to respire but the ones involved in decay respire anaerobically so they dont need oxygen