2- Organisms in the environment Flashcards
What is the process for photosynthesis?
Carbon dioxide is taken in by leaves, water is taken up by roots
Chlorophyll traps light energy which is used to convert carbon dioxide and water into glucose
Realising oxygen as a by-product of photosynthesis
What is the equation for photosynthesis?
Carbon dioxide + water ————–> glucose +oxygen
(+Light energy)
How do you test for starch in plants?
Test the green parts of a leaf with iodine solution and see if it goes a blue-black colour. If so, starch is present and photosynthesis has taken place
What can potentially slow down the rate of photosynthesis?
Limiting factor
Lack of light
Too Cold or hot (enzymes won’t work effectively when cold, destroyed if hot)
Too little carbon dioxide
How do plants use glucose?
Convert it into insoluble starch, fats or oils for storage
Use for respiration
Use to produce cellulose (cell wall strengtheners) or proteins
What (except for glucose) do plants need to produce proteins and where do they get them from?
Mineral ions such as nitrate ions
They get them from the soil
What factors may affect the distribution of organisms?
Temperature Availability of nutrients and water Amount of light Availability of oxygen and carbon dioxide (mountain and water animals) Pollution Amount of predators
What two methods using a quadrat can be used to measure the distribution of organisms?
Quantitative sampling - a sensible amount of quadrants randomally placed in a certain area, counting the number of x organisms you find inside the quadrat
Transect sampling - every y metres, a quadrat is placed and the amount of x organisms is counted
How valid is the data for measuring organisms?
Often quite inaccurate because the variables can not be controlled.
The morning organisms would be different to the night time, the season would effect results
If done accurately, it would take multiple visits and a lot of time
