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Flashcards in 4. Energy Flow Deck (13)
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1
Q

What do all the organisms in a community need?

A

a supply of energy

2
Q

Where do plants, algae and some bacteria get their energy from? What are these organisms called? Why?

A
  • light energy and convert it by photosynthesis into chemical energy in carbon compounds
  • producers
  • because they produce their own food
3
Q

Where do consumers, detritivores and saprotrophs obtain energy from?

A
  • chemical energy in the carbon compounds in their food

HOWEVER

  • carbon compounds and the energy contained in them move from organism to organism along food chains, but all food chains start with a producer that originally made the carbon compounds by photosynthesis.
  • light is therefore the initial source of energy for the whole community
4
Q

Draw the diagram explaining energy sources. p56

A

-

5
Q

What does food contain? How is it passed along?

A
  • energy

- by food chains

6
Q

How does a food chain occur?

A

when the primary consumer feeds on the producer, and the secondary consumer feeds on the primary consumer, etc.

7
Q

What happens the further up the food chain you go? Why?

A
  • less food is available and therefore less chemical energy

- due to loss of food and energy between the stages in a food chain

8
Q

What are the three ways by which food and energy can be passed to detritivores or saprotrophs rather than to the next stage in the food chain?

A
  • some organisms die before they are eaten by the next organism in the chain e.g. foxes do not eat every rabbit; some rabbits die from disease
  • some parts of organisms are not eaten e.g. bones, hair, gall bladders
  • some parts of organism are indigestible e.g. cellulose in food eaten by humans so is egested in feces
9
Q

Name another cause of energy loss, that isn’t: death; parts not eaten; parts indigestible.

A

cell respiration - use energy for essential process such as muscle contraction and active transport

10
Q

What is the energy conversion in cellular respiration?

A

chemical to heat

- heat is then lost from the organism

11
Q

Can any organisms convert heat energy back into chemical energy? What happens to it?

A
  • no

- heat is eventually lost from the ecosystem

12
Q

Organisms cannot convert heat energy back into chemical energy and heat is lost from the ecosystem. What is the significance of this?

A

ecosystems need an energy source, usually light, to replace energy lost

13
Q

Summarise energy transfer in an ecosystem with a chart. p56

A

-

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