Energy And Biomass In Food Chains COPY Flashcards
How much of the light that reaches them do green plants and algae absorb
A small amount
What happens during photosynthesis
Light energy is transferred to chemical energy
Where is the energy from photosynthesis stored
In the substances that make up the cells of the plants
The mass of living material (biomass) at each stage in a food chain is LESS than it was at the previous stage because
Some materials and energy are always lost inter organisms waste materials. Respiration supples all the energy needs for living processes, including movement. Much of this energy is eventually transferred to the surroundings
The biomass at each stage can be drawn to scale and shown as a
Pyramid of biomass
The efficiency of food production can be improved by
Reducing the number of stages in a food chain. This is because fewer energy losses occur along a shorter food chain, meaning a greater proportion of the energy that entered the food chain is available to humans and more people can be fed.
The efficiency of food production can also be improved by
Restricting energy loss from food animals by limiting their movement and by controlling the temperature of their surroundings
Fish stocks in the oceans are DECLINING. What is it important to do to prevent certain species from disappearing altogether in some areas
It is important to maintain fish stocks at a level where breeding continues
Which things play an important role in the conservation of fish stocks
Net size and fishing quotas
Practical solutions for human needs may require compromise between competing priorities, including
The differences in efficiency between producing food from animals and plants. The issues associated with farming of animals The implications of food miles
Why do living organisms remove materials from the environment and what happens to them eventually
Living organisms remove materials from the environment for growth and other processes. These materials are returned to the environment either in waster materials or when living things decay
Why do materials decay
They are broken down (digested) by micro organisms.
What type of conditions are micro organisms more active in and digest materials faster
Warm, moist, aerobic conditions
What does the decay process release
Substances that plants need to grow
In a stable community, the processes that remove materials are balanced by
Processes that return materials. The materials are part of a constant cycle.
The constant cycle is called
The carbon cycle
What is the source of energy for most communities of living organisms
Radiation from the sun
Why is the mass of living material (biomass) less at each stage than it was at the previous one
At each level in the chain, energy/biomass is lost through waste (eg faeces) or through respiration and associated processes (such as movement and maintaining body temperature). -some materials and energy are always lost in the organisms’ waste materials -respiration supplies all the energy needed for living processes, including movement. Much of this energy is eventually transferred to the surroundings
What are the issues associated with factory farming of animals
It causes reduced animal welfare, increased risk of injury, and increased risk of diseases (eg salmonella amongst chickens).
Food miles argument
In order to supply cheap produce all year round, many supermarkets import food from other countries around the world - where it is cheaper to produce or grows more plentifully. Some developing countries rely on food exports to the UK to generate income. However, the greater the distance the food has travelled, the greater the impact on the environment. This is due to the pollution from carbon dioxide emissions, generated by the transporting vehicles. A compromise must be found between the monetary cost to the consumer, the impact on developing economies and the environmental cost of the pollution associated with transporting food over such long distances.
