Unit 3 Topic 1 - Food Supply, Plant Growth And Productivity Flashcards
what is food security?
when at all times people are able to physically access food of sufficient quality and quantity
what is food supply?
the term used to refer to the availability of food for individuals
what does sustainable food production mean?
food must be sustainable without degrading the natural resources on which agriculture depends (eg. land and water supply)
what are four foods that contain alot of starch?
maize, potatoes, onions and lentils
what are some ways of improving plant growth?
breeding higher yeilding cultivars, using fertilisers, protecting crops from pests/ disease/ compitition
why is it important to use biodegradable substances?
so they do not contaminate the land after use
what is a pesticide?
a chemical used to protect from pests (eg green fly)
what is a fungicide?
a chemicsl used to protect from fungal diseases ( eg. blight)
what is a herbicide?
a chemical used to protect from weed competition
what is a trophic level?
the position which an organism occupies in the food chain
explain the trophic levels and their relation to producers, primary, secondary and tertiary consumers
food chains start at trophic level one, this is where producers are, priimary consumers are at trophic level 2, secondary consumers at trophic level 3 and tertiary consumers at level 4
how much energy is lost between trophic levels?
90%
what is photosynthesis?
the process in which plants make food using light energy
what is the word equasion for photosyntheseis
enzymes
water+CO2———> oxygen+glucose
light &
chlorophyll
what happens to the light energy that is not absorbed during photosynthesis?
it is reflected or transmitted
