B4 - It's A Green World Flashcards
B4 - It’s A Green World
What are the disadvantages of biological control?
Predator might not eat pest. May eat useful species. Predators population may increase and get out of control. Predator might not stay in area it is needed.
B4 - It’s A Green World
How can farmers use herbicides to intensively farm?
To kill weeds. This means more of Suns energy falling on fields goes to crops and not other competing plants that aren’t wanted.
B4 - It’s A Green World
What does turgid mean?
When a plant cell is well watered and plump or swollen.
B4 - It’s A Green World
Temperature - warmer decays faster due to speeding up respiration in microorganism so. Amount of water - faster when moist. Amount of oxygen - decay faster when available, micro organisms need to respire aerobically.
What three things does the rate of decay depend on?
B4 - It’s A Green World
How and why do the stomata open and close automatically?
Close when water supply in roots dries up. Guard cells have special kidney shape which closes/opens when guard cells become flaccid/turgid. Thin outer walls and thick inner walls makes function properly. Open allows gases for photosynthesis. Sensitive to light - open in day, close night to conserve water
B4 - It’s A Green World
Lots of fertilisers need to be added. No soil to anchor roots and support plant.
What are the disadvantages of hydroponics?
B4 - It’s A Green World
What does crenation mean?
If a cell loses too much water it completely shrivells up.
B4 - It’s A Green World
What happens to the rate of decay at optimum conditions?
Microorganisms grow and reproduce faster meaning there’ll be more of them to decay organisms.
B4 - It’s A Green World
Populations of different species in a habitat
What is the community?
B4 - It’s A Green World
Gradual change in distribution of species across a habitat.
What is zonation?
B4 - It’s A Green World
What is zonation?
Gradual change in distribution of species across a habitat.
B4 - It’s A Green World
What is the population?
All organisms of one species in a habitat
B4 - It’s A Green World
What is biodiversity?
A measure of variety of life in an area.
B4 - It’s A Green World
Describe a stem cross section…
Stems need to resist bending. The xylem forms a sort of ‘scaffolding’. Phloem is always around outside of stem.
B4 - It’s A Green World
Using living things instead of chemicals to control a pest.
What is biological control?
B4 - It’s A Green World
Increased light intensity, increased temperature, increased air movement, decrease in air humidity.
What 4 factors increase transpiration?
B4 - It’s A Green World
How does adding sugar or salt reduce the rate of decay?
If there’s a high concentration of salt or sugar around decomposers they’ll lose water by osmosis. This damages them and mean they can’t work properly. Things like tuna and olives are often stored in brine.
B4 - It’s A Green World
To help enzymes needed for photosynthesis and respiration. If there’s not enough potassium in soil, plants have poor flowers/fruit growth and discoloured leaves.
What is potassium useful for in plants?
B4 - It’s A Green World
What are the benefits of transpiration?
Constant stream of water keeps plant cool. Provides constant supply of water for photosynthesis. Water creates turgor pressure which helps to support it. Minerals can be brought in.
B4 - It’s A Green World
What is potassium useful for in plants?
To help enzymes needed for photosynthesis and respiration. If there’s not enough potassium in soil, plants have poor flowers/fruit growth and discoloured leaves.
B4 - It’s A Green World
Why do plants need magnesium?
Magnesium is one of most significant (but not in biggest amounts). Required for making chlorophyll for photosynthesis. Plants without enough magnesium have yellow leaves
B4 - It’s A Green World
Food lasts longer in freezer because decomposers can’t reproduce at all at such low temperatures.
How does freezing reduce the rate of decay?
B4 - It’s A Green World
What do Xylem Vessels do?
Carry water and minerals from roots up shoot to leaves in transpiration stream.
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Loss of water from a plant.
What is transpiration?
B4 - It’s A Green World
What controls the stomata and when they open/close?
Guard cells
B4 - It’s A Green World
Magnesium is one of most significant (but not in biggest amounts). Required for making chlorophyll for photosynthesis. Plants without enough magnesium have yellow leaves
Why do plants need magnesium?
B4 - It’s A Green World
Close when water supply in roots dries up. Guard cells have special kidney shape which closes/opens when guard cells become flaccid/turgid. Thin outer walls and thick inner walls makes function properly. Open allows gases for photosynthesis. Sensitive to light - open in day, close night to conserve water
How and why do the stomata open and close automatically?
B4 - It’s A Green World
Making cell walls
What is cellulose used for?
B4 - It’s A Green World
Square frame allows you to study a small area and scale up findings to make an estimate for a larger area.
What is a quadrat used for?
B4 - It’s A Green World
Why are organic fertilisers used?
Recycles nutrients left in plants and animal waste. Doesn’t work as well as artificial fertiliser but better for environment.
B4 - It’s A Green World
Physically removing weeds rather than spraying herbicide. More labour intensive but no chemicals involved.
How does weeding help organic farmers?
B4 - It’s A Green World
What methods are used to reduce the rate of decay?
Canning, cooling, freezing, drying, adding salt/sugar, and adding vinegar.
B4 - It’s A Green World
Upper epidermis, palisade mesophyll layer, spongy mesophyll layer and lower epidermis
What are the four layers in a leaf?
B4 - It’s A Green World
Number of 1st sample x number in 2nd sample ÷ number in 2nd sample previously marked
How do you calculate population size?
B4 - It’s A Green World
Guard cells
What controls the stomata and when they open/close?
B4 - It’s A Green World
What are the advantages of hydroponics?
Mineral levels can be controlled more accurately. Disease can be controlled more effectively.
B4 - It’s A Green World
Woodlands and lakes
Give two examples of natural eco systems…
B4 - It’s A Green World
Another method of intensive farming where plants are grown in nutrient solutions instead of soil. Often used to grow glasshouse tomatoes on commercial scale, as well as grow plants in areas with barren soil.
What is hydroponics?
B4 - It’s A Green World
No changes in population size due to deaths, immigration or emigration. Sampling method was set up same way each time. Markings haven’t affected animal’s chance of survival.
What assumptions have to be made when using capture and recapture?
B4 - It’s A Green World
What are the advantages of biological control?
No chemicals used, so less pollution, disruption to food chains and risk to people. No need to keep repeating treatment.
B4 - It’s A Green World
What assumptions have to be made when using capture and recapture?
No changes in population size due to deaths, immigration or emigration. Sampling method was set up same way each time. Markings haven’t affected animal’s chance of survival.
B4 - It’s A Green World
What is active transport?
Uses energy from respiration to help plant pull minerals into root hair against concentration gradient - from low concentrations to high concentrations.
B4 - It’s A Green World
Growing crops in cycle. Stops pest and diseases for one crop building up - stops nutrients running out. Most crop rotations include nitrogen fixing crop like legumes - put nitrates back into soil.
What is crop rotation in organic farming?
B4 - It’s A Green World
How does cooling reduce the rate of decay?
Putting food in a fridge slows down decay because it slows decomposers’ reproduction rate.
B4 - It’s A Green World
What is a plasmolysed cell?
If plant is short of water, cytoplasm starts to shrink and membrane pulls away from cell wall - but inelastic cell wall keeps things in position, just droops a bit.
B4 - It’s A Green World
What three things does the rate of decay depend on?
Temperature - warmer decays faster due to speeding up respiration in microorganism so. Amount of water - faster when moist. Amount of oxygen - decay faster when available, micro organisms need to respire aerobically.
B4 - It’s A Green World
What does Flaccid mean?
When a plant doesn’t get enough water from soil, plant begins to wilt because turgid pressure no longer there.
B4 - It’s A Green World
Give two examples of natural eco systems…
Woodlands and lakes
B4 - It’s A Green World
Feed on dead and decaying material (detritus). Examples include earthworms, maggots, and wood lice. As these feed on decaying material, they break it up into smaller pieces to give a bigger surface area to speed up decay.
What are detritivores?
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What is the term for non-living conditions?
Abiotic
B4 - It’s A Green World
Abiotic
What is the term for non-living conditions?
B4 - It’s A Green World
How is a disease used in biological control?
Myxomatosis - disease which kills rabbits. Myxoma virus released in Australia as biological control when rabbit population grew out of control and ruined crops.
B4 - It’s A Green World
For storing in seeds
What are lipids used for?
B4 - It’s A Green World
What happens in transpiration?
Caused by evaporation and diffusion of water vapour inside leaves. Creates shortage of water in leaf so more water is drawn up through xylem vessels. More water is drawn up through roots so there is a constant transpiration stream through plant.
B4 - It’s A Green World
What are detritivores?
Feed on dead and decaying material (detritus). Examples include earthworms, maggots, and wood lice. As these feed on decaying material, they break it up into smaller pieces to give a bigger surface area to speed up decay.
B4 - It’s A Green World
Organic farmers use less chemicals. Better for environment, less chance of river pollution - no use of pesticides = less wildlife harm. To be classed as organic it needs to follow ethical treatment of animals. No battery farming.
What are the advantages of organic farming?
B4 - It’s A Green World
They let carbon dioxide out and oxygen in, whilst also allowing water to escape (transpiration).
How does having stomata adapt a plant for photosynthesis?
B4 - It’s A Green World
Transport food - mainly sugars - both up and down stem to growing and storing tissues - movement is known as translocation.
What do phloem tubes do?
B4 - It’s A Green World
Vinegar is acidic ad acid kills decomposers.
How does adding vinegar reduce the rate of decay?
B4 - It’s A Green World
Describe a root cross section…
Roots have to resist crushing as they push through soil. Xylem in centre to give it strength.
B4 - It’s A Green World
Predator might not eat pest. May eat useful species. Predators population may increase and get out of control. Predator might not stay in area it is needed.
What are the disadvantages of biological control?
B4 - It’s A Green World
What are saprophytes?
Feed on decaying material by extracellular digestion which means they excrete digestive enzymes on material outside their cells. Enzyme breaks down material into smaller bits which can be absorbed by saprophyte. Many are fungi.
B4 - It’s A Green World
Why is glucose turned into starch?
It can’t dissolve and move away from storage areas in solution. It doesn’t affect water concentration inside cells - soluble substances would bloat storage cells by drawing in water.
B4 - It’s A Green World
A measure of variety of life in an area.
What is biodiversity?
