Unit 9 - Ecosystems And Material Cycles Flashcards
What is parasitism
A kind of feeding relationship where the parasite benefits by feeding off the host organism, causing harm to the host
Give an example of a parasite that lives on the outside of a host
Lice
Give an example of a parasite that lives inside a host
Tapeworms
Give 2 adaptations of tapeworms
Hooks and suckers attach head into host’s intestines
Segments contain male and female sex organs so fertilisation can occur
Give 2 adaptations of lice
Sharp claws to grip hair and skin
Sharp mouthparts to pierce skin and suck blood
What is a mutualities relationship
When organisms live together and they both benefit
How is are flowers and insects in a mutualistic relationship
Flowers can fertilise and insects get food from pollen
How is sea anemone and clownfish in a mutualistic relationship
Sea anemones protect clownfish using stinging tentacles, clownfish chase off predators and provide nutrients in faeces
How does Cora, polyps and algae form a mutualistic relationship
The algae are protected by coral, the algae photosynthesises and share food with coral
What do plants need to stay alive (7)
Space, light, water, carbon dioxide, oxygen, warmth, mineral ions
What is an ecosystem?
A large area where certain organisms live
Why are some species interdependent?
They rely on each other for resources
What is abundance
A measure of how common something is in an area such as its population size
What piece of equipment is used to estimate the population size
A quadrat
What is the equation for population size
Population size = no. Organisms x total size of the habitat/ total area of quadrats
What is biomass
The mass of tissues (living organisms)
Where is the energy from the sun transferred (2)
To substances in plant biomass, to environment by heating
For a primary consumer, where is the energy transferred? (3)
Into its faeces, into the secondary consumer, to the surrounding ps by heating
What are trophic levels?
The feeding levels of a food chain
What does a pyramid of biomass show?
The biomass of each different level in the food chain
What are the 5 levels of the food chain
Producer, primary consumer, secondary consumer, tertiary consumer, trophic level
How does the pyramid of biomass show that there is a limit to a food chain
The energy stores decrease too support another level
What is the distribution
Where animals are found in and ecosystem
What are abiotic factors?
Non-living factors
What is a belt transect?
When quadrats are placed along a line and the abundance of organisms is measured
What is essential for algae to grow?
Light
Why do quadrats need to be placed carefully on a coral reef (2)
To avoid damaging organisms and prevent scientists from being cut
Explain the core practical - Quadrats and transects
Peg out a long tape measure that goes into and out of shade
Make measurements of a chosen plant along regular intervals
Record abundance of selected plants in quadrat
What is a transect line
A line (usually tape measure) that is used to show where to place quadrats
What are biotic factors
Living organisms
Give an example of a biotic factor
The number of wolves decreased due to hunting which caused there to be more elks which caused overgrazing of trees
What is biodiversity
The number of different species
What are lecanora conizaeoides?
A species of lichen
Why can lichens be used as an indicator species for sulphur dioxide?
Different species of lichens can tolerate different amounts of sulphur dioxide
What is another indicator of air pollution besides lichens
Blackspot fungus which can’t grow well with pollution and are pathogens of roses
What is eutrophication?
Excessive richness of nutrients in an ecosystem e.g too much fertilisers
Why is water pollution bad (details)
Substances in pollution cause eutrophication which encourage rapid growth of algae and plants. The bacteria feed on the dead plants and reduce oxygen concentration in water which kills other animals
What is used to collect numerical data of water and air pollution
Sensors
What is the aim of fish farming?
To produce more fish and so reducing overfishing of wild fish
How does fish farming cause problems (2)
Uneaten food and faeces sink to bottom which changes conditions and may harm wild organisms
Parasites and diseases spread easily
What are indigenous species
Native species (always been there)
What are non-indigenous organisms?
Organisms that haven’t always been there
Why might some species be introduced to an ecosystem?
To bring down numbers of certain species
How does eutrophication happen?
- Fertiliser added
- Heavy rain washes it off, nitrates and phosphates dissolve in water
- Nitrates and phosphates not taken by plants are washed into river
- This encourages plants and algae to grow rapidly
- Surface plants block sunlight so plants die in water and less O2 is then produced
- Bacteria that break down plants and use oxygen
- Less oxygen which causes marine life to die
Why might several different trees be planted in reforestation
To increase range of habitats and biodiversity
What is conservation
When an effort is made to protect rare and endangered species
Why else is it important to protect species besides for their own good
We use plants and animals for food
Use plants for medicine
Areas with greater biodiversity recover faster from natural disasters
What does food security mean
Having access to enough sage and healthy food for all times
Give 2 ways to improve food security
Using fertilisers and improving agricultural methods
Why might food security be more difficult
Population increase
How much more protein is produced from soybean compared to animals using the same land area
15 times more
Why are there sustainability concerns regarding fertilisers
They are made using chemical processes which need energy and release CO2
What does sustainable mean
If it is possibly to continue without causing harm for the future
What is a vector
An organism that doesn’t cause harm itself but can transfer a disease
What are biofuels and why are they more useful
When plants are made into oil and energy resources which when burned, only release the amount of CO2 that the plant originally took in
How much of the body is water
60%
What is transpiration
Plants absorbing water
What is infiltration
Water being absorbed into the ground
What does potable water means
Safe to drink
Why is fresh water e.g in lakes treated with chemicals and filtered
To remove dirt, pathogens and toxic substances
What is desalination?
Obtaining fresh water from sea or salty water
What method does desalination use
Distillation
How does a fungus play a key role in the carbon cycle
It grows inside the cow faeces and digests carbon compounds. It produces capsules with spores (new fungi) and the capsules explode off the top of the stalk and onto grass, this is eaten bit the fungus isn’t digested so then returns to the faeces.
What happens to carbon dioxide inside a leaf
The carbon atom becomes another compound called glucose
What 2 things is glucose used for in a plant
Respiration and biomass
When an animal eats a plant, what happens to the carbon compounds in the plant
They are digested or leave in the animals faeces
What do the absorbed carbon compounds do in the animals body? (3)
Respiration, to build more complex compounds in tissue, some form waste products in urine
What is decay caused by
Microorganisms called decomposeds
Give 2 tropes of decomposes
Fungi, bacteria
What do decomposers use carbon compounds for? (2)
Respiration and to make complex compounds in their cells
What happens to dead plants if there are too many for decomposes to break down
Over millions of years, they change to coal by heat and pressure of the earth
How is natural gas and oil formed
When animals and sea plants aren’t broken down by decomposers but are compressed
How much nitrogen is there in the atmosphere
Around 80%
Where is nitrogen in plants
Proteins and DNA
Where do plants absorb nitrates from
Nitrogen compounds dissolved in soil water
What do decomposers do with nitrogen compounds
They release nitrogen compounds with carbon compounds when they decompose plants into the soil
What are nitrogen-fixing bacteria?
Soil bacteria that can convert nitrogen gas into nitrogen compounds in the soil
How do some plants have a mutualistic relationship with bacteria
The coddles in the plant root protect the bacteria and the plant gets nitrogen compounds
How do farmers make use of the mutualistic relationship between pea plants and bacteria
They plant a crop of peas and dig in the roots after the crop has been harvested so the next crops will benefit from the additional nitrogen compounds
What is crop rotation
Planting a sequence of different crops in different years
Give 4 ways for food preservation
Reducing temp, reducing water, irradiation, reducing oxygen
What is compost
Waste garden material that is collected and contains many nutrients that were plant tissues
Why might compost be turned every few weeks?
To let more oxygen in from the sides
What is the equation for the rate of decomposition
Rate of decomposition = mass lost/ no. of days
