Sustainability & interdependence Flashcards
(23 cards)
What does the increase in human population and concern for food security lead to?
A demand for increased food production
Food production must be what?
Sustainable and not degrade the natural resources on which agriculture depends.
What is food security?
Food security is a measure of the availability of food required to support people of a household, region, country or any specified area.
What can be added to crops to remove factors which may be limiting plant growth?
Minerals (fertiliser) or water
What can be used to protect crops from disease, pests and competition?
Pesticides, fungicides and herbicides
What are two ways to help improve crop yield?
Replace existing strain of crops with higher yielding cultivar
Develop pest resistant crop plants
How is energy lost from the food chain?
Undigested food and waste
Movement
Heat
What % of energy is actually incorporated into body tissue?
10%
What happens as you move along a food chain?
Energy is lost between each trophies level and the next
What is the photosynthesis equation?
Carbon dioxide + water —> Glucose + oxygen
What is photosynthesis?
The process by which green plants trap light energy and use it to make carbohydrates
What is a wavelength?
The distance between two crests on a wave
What is a wavelength measured in?
Nanometers
Light hitting a leaf will be what?
Absorbed
Reflected
Transmitted
What are the three pigments in a leaf?
Chlorophyll a
Chlorophyll b
Carotenoid
Chlorophyll a and b do what with light energy?
Absorb light
What does the absorption spectra show?
It shows the wavelengths if light absorbed by the different pigments in a leaf
Why are chloroplasts green?
Because they absorb every other colour
Most light is absorbed by which regions on an absorption spectrum?
Most light is absorbed by the blue and red regions
What happens in the green region of an absorption spectrum?
Limited absorption most light is reflected or transmitted
What do carotenoid la do?
Extend the range of wavelength available for photosynthesis and pass this energy onto chlorophyll a
Why is it useful for a plant to have several different pigments?
They can absorb more of the wavelength of light
What does the action spectra do?
It shows how effective the different wavelengths of light are at photosynthesis
