Food Supply, Plant Growth and Productivity (2) Flashcards
What is food security?
The ability to access food in sufficient quantity and quality.
Why is there a higher demand for food?
The rising population.
What is access in terms of food security?
Being able to afford it.
Why must food production be sustainable?
To not have a negative impact on the ecosystem and natural resources.
What is needed to maintain a sustainable food supply when producing more food in the same area of land?
- increased plant productivity
- manipulation of genetic diversity
What are the four plant crops from which most human food comes?
- cereals
- potatoes
- roots
- legumes
What does all food production rely on?
Photosynthesis
What are the four factors that control plant growth?
- Light
- Nutrients
- Water
- Competition
How can you improve the efficiency of food production (four ways)?
- Control of limiting factors - use of fertilisers for example
- Planting crops with a higher yield
- Removing competition - pesticides, fungicides, herbicides
- Developing pest-resistant crops
Why is the production of livestock less efficient than growing crops?
90% of energy is lost between each trophic level - requires a lot more energy and water.
When can livestock be more efficient than growing crops?
When the habitat is unsuitable for growing crops.
How can humans be more sustainable?
Eat more vegetables and cut down on meat.
What is photosynthesis?
The process by which green plants trap light energy and use it to make carbohydrates.
What happens to the 100% of the light that strikes a leaf?
12% is reflected
5% is transmitted through the leaf
83% is absorbed by the pigments within the chloroplasts
What percent of the light that strikes the leaf is actually used for photosynthesis?
4%
