Unit 3.4.5 - Energy Transfer Flashcards
What is an ecosystem?
All the organisms living in a particular area and all the abiotic conditions.
What is the main route by which energy enters an ecosystem?
Photosynthesis
How is energy transferred through the living organisms of an ecosystem?
When they eat each other.
What two diagrams show how energy is transferred through an ecosystem?
Food chains and food webs.
Why is there very rarely quaternary consumers?
Because the is so much energy lost between trophic levels there wouldn’t be enough energy in tertiary consumers for quaternary consumers to survive.
What does autotroph mean?
It is when something produces their own food.
What in the food chains are autotrophs?
Producers
What does heterotroph mean?
It when something gets their food from other organisms.
What in the food chains are heterotrophs?
Consumers
Usually what percentage of energy is passed on to the next trophic level?
10%
Is energy lost through growth of an organism and why?
No, because the energy still remains in the organism as biomass.
Give three reasons why energy is lost between light and the producer
- Not all light hits the plants. 2. Light might not hit a chlorophyll. 3. Light can be of the wrong wave length.
Give five reasons why energy is lost between the producer and the primary consumer.
- Not all plant material is eaten (roots) 2. Some plant material isn’t digested (cellulose) 3. Some energy is used by the plants (active transport) 4. Energy is lost through respiration 5. Some tissues like leaves die and decompose by decomposers.
Give seven reasons why energy is lost between the consumers.
- Not all the animal is eaten (bones) 2. Not all the animal material is digested 3. Some materials/energy is excreted in urine and faeces. 4. Energy is lost by maintaining a constant body temperature. 5. Energy is lost through respiration. 6. Some tissues die and are decomposed by decomposers. 7. Energy is lost through movement (respiration)
What formula can you use to calculate the efficiency of energy transfer?
How does the efficiency of energy transfer change as you move through the food chain?
It increases.
Why is energy transfer the least efficient from the sun to the producer?
So much energy is lost as it cannot be absorbed.
How does the efficiency of energy transfer differ from producer to consumer than from consumer to consumer?
Less efficient from the producer to consumer.
Why is energy transfer less efficient from producer to consumer than from consumer to consumer?
Plants contain a greater proportion of indigestible materials than animals.
How does the efficiency of energy transfer differ from warm blooded organisms to cold blooded organisms?
Less efficient in warm blooded organisms.
Why is energy transfer less efficient in warm blooded organisms than cold blooded organisms?
Warm blooded organisms use a lot of energy from respiration to keep their body temperature constant.
What do pyramid of numbers represent?
The relative number of organisms in an ecosystem at a given moment irrespective of biomass.
What are the three types of pyramids you can use to represent food chains?
- Pyramids of numbers 2. Pyramids of biomass 3. Pyramids of energy
What are the units for pyramids of numbers.
the number m-2y-1
Why are pyramids of numbers not always pyramid shaped?
One producer could sustain a lot of primary consumers (tree).
What do pyramids of biomass represent?
Relative biomass of organisms in an ecosystem at a given moment irrespective of numbers.
What is biomass?
The amount of organic material in an organism.
What is the units for pyramids of biomass?
kg m-2y-1
Why are pyramids of biomass usually pyramid shaped
Because biomass/energy is lost at each trophic level.