Transcript Producers & Consumers

Sunday, April 10, 2016
Producers & Consumers
 To know how energy is passed from producers to consumers in
food chains
Food Chains
 What is a food chain?
 A food chain shows the different organisms that live in a
habitat, and what eats what
 A food chain always starts with a producer, which is an
organism that makes food (usually a green plant, because
plants can make their own food by photosynthesis)
 A food chain ends with a consumer, which is an animal that
eats a plant or another animal
grass  cow  human
*The arrow points to the organism that is doing the eating
Food Chains
 There are some more key words within a food chain – study the
following food chain, and try and work out what some of the
key food chain words are, and what they mean…
Food Chains
 The plant is the producer and the animals are consumers
 The first consumer in the chain is also called the primary
consumer, the next one is the secondary consumer and the one
after that is the tertiary consumer…
 A consumer that eats plants is called a herbivore
 A consumer that eats other animals is called a carnivore
 An omnivore is an animal that eats plants and other animals.
Food Webs
 In most habitats organisms normally eat / are eaten by more
than one other organism
 To represent this we use food webs (like food chains but they
interlink with one another, e.g. a pond
 Here the producers are the pondweed and the
microscopic algae
 Dragonfly nymphs and brown trout eat the
mayfly nymphs
 The brown trout also eats the dragonfly
nymph
 The freshwater shrimp are eaten by the
dragonfly nymph and the brown trout
Energy
 The arrow shows the energy being transferred from one
organism to the next
 Between each step energy is lost in a variety of ways, including:  Growth of the organism
 Reproductive costs
 Lost through waste products (poo)
 Lost through heat
 This is why food chains are not infinitely long – energy is lost from
one stage to the other
Energy
 Complete the energy from
plants worksheet
Energy From Plants
1.
Plants produce food (glucose) which is useable energy for
other organisms
2. Some energy is used up in the plant, such as for respiration /
reproduction / growing etc…
3. 6% of the energy is used (60% is lost as waste, and 34% is lost
via respiration)
4. a) 34% of 3000 = 1020 units; b) 60% of 3000 = 1800 units
5. Energy is lost as the cow how been respiring and used up
some of the potential plant energy. Also, not all parts of the
cow are eaten!
6. Growing crops and eating them is much more energy efficient
than farming animals as there is less energy wastage
Energy Transfer
 Think of your favourite person in the world...!
 E.g. a sports person / actor / musician etc…
 Try and explain how they live, in terms of a food chain
(diagrams may help)
Sun  grass  cow  human
Glucose
 Plants produce glucose (their food) via photosynthesis
 However, they normally sore this glucose as starch (as it is
insoluble), e.g. a potato
 Why is it that plants store
glucose within fruit?!
 The fruits contain sugars to
encourage animals to eat
them (which helps with seed
dispersal)
Glucose
 Complete the glucose
worksheet
Glucose
1.
2.
3.
4.
Photosynthesis
Starch is found within the chloroplasts
Potato
Plants store starch so they have access to the energy when
the need it (it is also insoluble, making it a good storage
material)
5.
6. Cellulose is found within the cell wall
7. Oils and fats are found in the cell membrane
8. glucose + oxygen  carbon dioxide + water (+energy)