3.1 Food Supply, Plant Growth and Productivity Flashcards
What is food security?
The ability of human populations to access food of sufficient quality and quantity
What causes a demand for increased food production?
Increase in human population and a concern for food security
What are the requirements for food production?
It must be sustainable and not degrade the natural resources on which agriculture depends
What does agricultural production depend on?
Factors that control photosynthesis and plant growth.
What are the factors that control plant growth?
Breeding of higher yielding cultivars, use of fertiliser, protecting crops from pests, diseases and competition
What are some plant crop examples?
Cereals, potato, roots ad legumes.
What are the 3 fates of light?
Absorbed, transmitted, reflected.
What does absorbed light energy do?
Excites electrons in a pigment molecule
What do excited electrons do?
Transfer through the electron transfer chain to release energy to generate ATP by ATP synthase
What happens in photolysis?
Energy is used to split water into oxygen, which is evolved, and hydrogen ions, which are transferred to the coenzyme NADP
What is the first step in the calvin cycle?
Enzyme rubisco fixes carbon dioxide by attaching it to ribulose bisphosphate (RuBP)
What is the second step in the calvin cycle?
3PG is phosphorylated by ATP and combined with hydrogen ions from NADPH to form G3P
What is the third step in the calvin cycle?
G3P is used to regenerate RuBP and for the synthesis of glucose
