B7 Ecology Flashcards
Ecosystem
Biotic and abiotic factors in a defined area
Habitat
A specific area where organisms exist
Community
All of the population of organisms in a habitat
Population
All of one species of organism in an area
Species
A group of living things that can breed together to create offspring who can reproduce
Individual
A single organism
Stable Community
Places with roughly balanced biotic and abiotic resources
e.g: ancient forest/ rainforest
Biotic Factor
Living factor
pathogens, food, predators
Abiotic Factor
Non-living factor
light, humidity, temperature, o2/co2 levels
Competition
2(+) organisms thriving for the same resources.
Can be the same or different species
Adaptations
Features living things have that help them survive and increase their chances of reproduction in their environment.
3 Types of adaptation
Functional,
Structural,
Behavioural
Functional
What goes on inside an organisms body (slow metabolism)
Structural
Features of an organisms body (camouflage)
Behavioural
Ways the organisms behave (migration)
State four factors plants compete with each other for.
Space, light, mineral ions, water
State three factors animals compete with each other for.
Food, mates, territory
What is interdependence?
Each species within a community depend on others for food, shelter, pollination, seed dispersal, etc. If one species is removed, this will affect the whole community.
State all 4 possible biotic factors which may affect a community.
Availability of food,
new predators,
new pathogens,
being outcompeted
Organisms have adaptations to enable them to survive in their usual conditions. What 3 categories do these adaptations fall under?
Structural,
behavioural,
functional
What is an extremophile?
An organism that lives in an extreme environment, such as at high temperature, pressure or salt concentration.
What do all food chains begin with?
Producers
What is a producer?
A photosynthetic organisms that produces biomass.
Give two examples of a producer.
Green plants and algae.
What does a producer make? How?
Glucose, through an exothermic chemical reaction known as photosynthesis.
Name 2 methods used by ecologists to determine the distribution and abundance of species in an ecosystem.
Random and systematic sampling.
Name 3 types of consumers and what they eat.
- Primary consumers eat producers.
- Secondary consumers eat primary consumers
- Tertiary consumers eat secondary consumers
What is a predator?
A consumer that kills and eats other animals.
What are prey?
An animal that is killed and eaten by predator.
Why are all materials in the living world recycled?
To provide the building blocks for future organisms.
What uses carbon dioxide in the atmosphere?
Plants during photosynthesis.
State three processes which return carbon from organisms to atmospheric carbon dioxide.
- Respiration – releases carbon dioxide.
- Release (carbon containing) waste – microorganisms decompose this and respire – releases carbon dioxide.
- Death – microorganisms decompose the body and respire – release carbon dioxide.
Where does the fresh water for animals and plants on land come from?
Continuous evaporation of water from oceans and precipitation over land.
State 3 factors which may affect the rate of decay of biological material.
- Temperature
- Water
- Oxygen availability
What is compost used for by gardeners and farmers?
Used as a natural fertiliser for growing plants and crops.
What is a biogas generator and how does it work?
A generator used to anaerobically decay biological material which produces methane gas as a fuel.
Name 3 environmental changes that affect the distribution of species in an ecosystem.
Temperature, availabilty of water, composition of atmospheric gases
State three causes of environmental change.
Seasons,
Geographic location,
Human interaction
How do humans reduce the amount of land available for other animals and plants?
Building,
Quarrying,
Farming,
Dumping waste
Why are peat bogs being destroyed?
To produce garden compost.
What effect does destruction of peat bogs have on an area?
Reduces biodiversity.
What happens as a result of decay or burning of peat?
Release of carbon dioxide into the atmosphere.
What is biodiversity?
The variety of all the different species of organisms on earth, or within an ecosystem.
Why does having great biodiversity ensure stability in an ecosystem?
Because species have reduced dependence of one another for food, shelter and maintenance of the physical environment.
What is human activity reducing, which may be an issue for the future of the human species on Earth?
Biodiversity.
What is happening to the levels of resources we are using and the waste we are producing as human population rapidly grows?
Increasing (dangerously).
What is the increased release of waste and chemical materials causing?
(More) pollution.
How is water polluted?
Sewage, fertilisers or toxic chemicals.
How is air polluted?
Smoke and acidic gases.
How is land polluted?
Landfill and toxic chemicals.
Why does pollution reduce biodiversity?
It kills plant and animals.
Give three causes of deforestation.
- Provide land for cattle or rice fields
- Grow crops for biofuels
- To clear space for building
Which 2 gases are increasing in the atmosphere and contributing to global warming?
- Carbon dioxide
2. Methane
What are the five main biological consequences of global warming?
- Increased spread of pathogens
- Affecting migration patterns of animals
- Melting of polar ice caps, causing flooding
- Reduced habitats in polar regions
- Reduced biodiversity
State three positive human interactions in an ecosystem.
- Breeding programmes for endangered species
- Protection and regeneration of rare habitats
- Reintroduction of field margins and hedgerows in agricultural areas where farmers grow only one type of crop
- Reduction of deforestation and carbon dioxide emissions by some governments
- Recycling resources rather than dumping waste in landfill
State two negative human interactions in an ecosystem.
- Clearing of land for agriculture, buildings and/or transport
- Hunting of rare species
- Mining from the land
Define Quadrat
A square frame enclosing a known area
What are the water and carbon cycles?
The prices by which water and carbon are recycled around the environment.
Define Decay
Microorganisms break down plants and animal waste to get energy.
Define compost
Decomposed matter
Which microorganisms carry out the process of decomposition?
Fungi and Bacteria
What effects the rate of decomposition?
Temperature
Oxygen Availability
Water Availability
Number of microorganisms
How is biogas produced?
Through anaerobic respiration
What is biogas mainly consistent of
Methane
Describe the investigation for rate of decay?
Place two test tubes in a water bath at 30C
(one should have 5cm^3 of lipase solution, the other should have 5cm^3 of milk with 5 drops of indicator and 7cm^3 of sodium carbonate - this should make it pink)
When the bath reaches 30, add a drop (1cm^3), start a stopwatch and stir
As soon as it turns colourless, stop the stopwatch.
Repeat at 10, 20, 30, 40 and 50*
Do this 3 times and take a mean
What is the equation for rate of decay?
1000/time
What indicator should we use when investigating decay?
Phenolphthalein
What are the properties of phenolphthalein?
Pink at pH 10 but colourless below 8.3 pH
Describe Biodiversity
Biodiversity is the variety of different species of organisms on Earth, or within an ecosystem
Why is high biodiversity important?
To ensure an ecosystem is stable as they depend on each other for shelter and food
Why has the population risen exponentially since the 1800s?
Modern farming and medicine
Why does the increasing population put strain on the environment?
Resources to Survive
More raw materials for increased standard of living
What does pollution effect in the environment?
Air
Land
Water
How does toxic waste effect the water?
Sewage and toxic chemicals from industry can pollute lakes, rivers and oceans, affecting the plants and animals that rely on them for survival.
Chemicals used on land can also be washed into water.
How does toxic waste effect the land?
We use toxic chemicals for farming. We also bury nuclear waste underground, and we dump a lot of household waste in landfill sites.
How does toxic waste effect the air?
Smoke and acidic gasses released into the atmosphere can pollute the air
What causes acid rain?
Sulphur Dioxide
How do carbon dioxide and methane contribute to global warming?
Greenhouse gasses create an insulating layer in the atmosphere
As radiation is reflected back off of the Earth, it hits these gasses and instead of passing through out if the atmosphere, it is reflected back down to earth.
As the layer thickens, more energy is reflected back to Earth.
