1. Feeding relationships
Boardworks KS3 Science 2008
Feeding Relationships
Feeding relationships

2. Food chains – who eats what?
Boardworks KS3 Science 2008
Feeding Relationships
Can you see a food chain in this habitat?
Feeding Relationship Worksheet1 accompanies this section.

3. Boardworks KS3 Science 2008 Feeding Relationships
Food chains
Boardworks KS3 Science 2008
Feeding Relationships
A food chain is a sequence that shows how each individual feeds on the organism below it in the chain. Each arrow means ‘eaten by’.
leaf
caterpillar
bird
fox
What does this food chain show?
A leaf is eaten by a caterpillar, which is then eaten by a bird, which is then eaten by a fox.
Energy is transferred from one organism to another in the direction of the arrow.

4. Food chains – draw your own
Boardworks KS3 Science 2008
Feeding Relationships
Draw your own food chains based on the following guidelines:
A food chain from a forest habitat.
A food chain from an ocean habitat.
A food chain with four organisms in it.
A food chain that ends with you!
Use arrows ( ) to show the transfer of energy between the organisms that you choose.

5. An Antarctic food chain
Boardworks KS3 Science 2008
Feeding Relationships

6. Producer, herbivore or carnivore?
Boardworks KS3 Science 2008
Feeding Relationships
Food chains always start with a producer.
If the producer is a plant, only a small part of it might be involved in the food chain, such as its seeds, fruits, leaves or even dead leaves.
From a food chain, we can tell if an organism is a producer, a herbivore or a carnivore.
leaf
snail
bird
owl
What are the feeding types of the animals in this food chain?

7. Boardworks KS3 Science 2008 Feeding Relationships
Name that feeding type
Boardworks KS3 Science 2008
Feeding Relationships

8. Boardworks KS3 Science 2008 Feeding Relationships
Ranking consumers
Boardworks KS3 Science 2008
Feeding Relationships
Consumers eat plants or animals, or both. A food chain can be used to rank different types of consumers.
seaweed
limpet
crab
human
producer
primary
consumer
secondary
consumer
tertiary
consumer
Producers – make their own food.
Primary consumers – eat producers.
Secondary consumers – eat primary consumers.
Tertiary consumers – eat secondary consumers.

9. Primary, secondary or tertiary?
Boardworks KS3 Science 2008
Feeding Relationships

10. Boardworks KS3 Science 2008 Feeding Relationships
What is a food web?
Boardworks KS3 Science 2008
Feeding Relationships
Why is it a good idea for an organism to have different sources of food? Animals usually eat many different things and are involved in lots of different food chains:
plants
aphid
ladybird
blue tit
owl
plants
moth
blue tit
owl
plants
vole
stoat
plants
vole
owl
Teacher notes
Why is it a good idea for an organism to have different sources of food? Reliance on only one source of food would make an organism vulnerable to variations in the availability of this food. Also, many food sources are not available all year round, so alternative sources of nutrition are needed.
These food chains can be put together in a food web,
which shows how the food chains are connected.
What would the food web for these food chains look like?

11. Boardworks KS3 Science 2008 Feeding Relationships
Food webs
Boardworks KS3 Science 2008
Feeding Relationships
owl
bluetit
chiffchaff
stoat
spider
moth
vole
ladybird
plant
aphid

12. Boardworks KS3 Science 2008 Feeding Relationships
Using a food web
Boardworks KS3 Science 2008
Feeding Relationships
1. Name the producer in this food web.
2. Name two herbivores in this food web.
3. Name two species that are top carnivores.
4. How many secondary consumers are there?
Teacher notes
1. Daisy (flower/plant)
2. Vole and aphid (moth is also an acceptable answer – adult moths usually don’t eat, but their larvae do)
3. Stoat and barn owl
4. Four (ladybird, spider, stoat, blue tit)
5. Daisy, moth, blue tit, barn owl Daisy, moth, spider, goldfinch, barn owl.
5. Which food chains include the moth?

13. Boardworks KS3 Science 2008 Feeding Relationships
Build a food web
Boardworks KS3 Science 2008
Feeding Relationships

14. Changes in the food chain
Boardworks KS3 Science 2008
Feeding Relationships
Nearly every species of animal is dependent on a number of other species for survival – this is called interdependence.
Currently human activity is damaging the natural habitats of many animals.
This will not only affect the animals in the area, but it could have far-reaching effects on the rest of the species in the food web.
Photo credit: Jupiterimages Corporation
Teacher notes
See ‘Ecosystems’ presentation for more about how changes in the environment can have an impact on animals.
If the population of a species declines dramatically how might this affect the other species that depend upon it?

15. Boardworks KS3 Science 2008 Feeding Relationships
Changes in a food web
Boardworks KS3 Science 2008
Feeding Relationships
Teacher notes
This activity is designed to show students that a decline in one species can have a significant impact on others. These values and outcomes are completely speculative.

16. Food chain populations
Boardworks KS3 Science 2008
Feeding Relationships