B7 - Ecology (P2) Flashcards
What is a habitat
The environment in which an organism lives
What is a population
The total number of organisms of same species living in the same geographical area
What is a community
The populations of all the different species that live in the same habitat
What is an ecosystem
How the biotic and abiotic parts of an environment interact
What do plants compete for
Light
space
Water
mineral ions
What do animals compete for
Food
water
mating partners
territory
What is interdependance
All the different species in a community depend on one another
What is a stable community
when the populations of the different species in a community remain fairly constant
What are biotic factors
The living parts of an environment
What are abiotic factors
The non- living parts of an environment
Give examples of biotic factors
Availability of food
The arrival of a new predator
Competition between species
New pathogens
Give examples of abiotic factors
Light intensity
Temperature
Water
pH and mineral content of soil
What are camels adapted to
The hot and dry conditions in a desert
How are camels adapted to the desert
- The hump stores fat
- Can perform metabolic reactions that turn fat into water
- A thick fur coat insulates the top of the camel form the heat which reduces water loss through sweating
What are behavioral adaptations
Adaptations to the animals lifestyle or behaviour
What are structural adaptations
Adaptations of body shape and structure
What are functional adaptations
Adaptations to the body functions of an organism
What is an adaptation
An inherited feature that enhances survival in the environment
What are cactuses adapted to
Living in dry conditions
How are cactuses adapted to dry conditions
- They have small leaves to reduce water loss
- They contain extensive and shallow roots to allow cacti to catch as much water as possible after rainfall
What are extremophiles
Organisms that are adapted to live in very extreme conditons
What conditions can extremophiles survive in
They can endure high pressure, high temperature and high concentrations of salt
What does a food chain start with
A producer
What is the role of the producer
Synthesise complex molecules
What are the producers the source of
All biomass in a community
Organisms that consume the producer are what
Primary consumer
Draw a food chain for grass, fox and rabbit
grass —-> Rabbit —-> Fox
What trophic level is the producer
Trophic level 1
What trophic level is the tertiary consumer
Trophic level 4
Going through a food chain does the number of species increase or decrease
Decrease
What percent of energy is passed on through a food chain
10%
What are the trends of a predator-prey cycle
The populations rise and fall in cycles
What is sampling
A method used to determine the number of organisms in an area
What are the two methods of sampling
Random sampling
Sampling along a transect
What is random sampling
Sampling using a quadrat to compare the number of organisms in different areas
How do you perform random sampling
Place a quadrat on the ground and count the number of organisms inside the quadrat and calculate the total population size
What organisms is random sampling used to calculate
Sampling plants or slow-moving animals
How do you calculate total population size
(total area/ area sampled) x number of organisms of the species in sample
What is a transect
A line e.g. tape measure or rope
What is sampling along a transect used to investigate
if the number of species changes as we move across a habitat
How do you perform sampling along a transect
Place a transect so it runs across the habitat, then use a quadrat to count the number of organisms at intervals on the quadrat
What are the conditions needed for decomposition
High temperature
Moist conditions
Good supply of oxygen
What can happen if the abiotic factors change
The distribution of species may change
What is biodiversity
The variety of all different organisms on Earth
Why is biodiversity important
Because species depend on one another for food and shelter
What happens if there is more biodiversity in an ecosystem
The environment becomes more stable
What is the effect of a stable ecosystem
There is less dependency on one species
How are humans reducing biodiversity in tropical forests
large areas are being destroyed (deforestation) to provide land for agriculture, housing etc
Why are humans using more resources than ever
Better standards of living and increased populations
What does sewage contain
Urine and faeces
What does sewage contribute to
Water pollution
What happens to sewage before it is released
It is treated
What are rivers and streams polluted with
fertilizers
What is the effect of fertilizers in streams
Reduce dissolved oxygen levels which kills aquatic organsims
Where does the carbon cycle start
Carbon dioxide in the atmosphere
How does carbon enter plants
Through photosyntheis
How does carbon dioxide return to the atmosphere from animals and plants
Aerobic respiration
What happens to the carbon in waste of dead animals
It forms fossil fuels or decomposes through fungi or bacteria
How is the carbon in fossil fuels returned to the atmosphere
Combustion
Why are decomposers important
- They cycle materials through an ecosystem
- They release mineral ions into the soil
What happens to dead animals if decomposers don’t function properly
The carbon is converted to fossil fuels
What happens to the water in clouds
It is released as precipitation ( rain, snow, sleet, hail)
What happens to the precipitation
The runoff is absorbed by the roots
What happens to the water in the roots
Evaporated and then condensed to form clouds
What is the importance of the water cycle
Plants need water for photosynthesis and growth
Animals rely on water and plant matter for food
What is the main contributor to air pollution
Combustion of fossil fuels
What does the combustion of fossil fuels release
Greenhouse gases
What is the main contributor to land pollution
Landfills
What is the effect of landfills on biodiversity
Destroys habitats which reduces biodiversity
What is the effect of landfills on biodiversity
Destroys habitats which reduces biodiversity
What is land used for
Infrastructure, agriculture, landfill, peat production, deforestation
What do peat bogs contain
Large amounts of dead plant materials
What causes peat bogs to have a lot of trapped carbon
The conditions for peat make decay very slow
What is peat used for
To produce cheap compost for gardens and farms
What is the effect of destroying peat bogs
- Reduces the variety of organisms so reduces biodiversity
- Large amounts of the trapped carbon is released into the atmosphere
What are the consequences of global warming
- Loss of habitats
- Change in the distribution of animals
- Changes in migration patterns
- Plants flower earlier
