Desirae Burger s1638736
Group A4
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Food Chains and Food Webs
Plants and Animals rely on each other for survival. As Loxley et al (2010) states: ‘Plants and Animals in
the same habitat depend on each other for their mutual benefit and survival’ (pp. 149). The relationship
between plants and animals can be categorized into two groups:


Producers
Consumers
Producers
Producers are organisms that produces organic compounds from simple molecules using energy from
the sun or chemical reactions (Loxley et all (2010). Plants are called Producers. They use a process
called photosynthesis to make food. Plants are very fortunate as they are the only specimen that can
produce their own food. That is why they are called producers.
Consumers
There are three types of consumers – primary consumer, secondary consumer and tertiary consumers.
Primary consumers are organisms that obtain their energy from primary producers (plants) Primary
consumers are also called Herbivores. Secondary consumers are organisms that obtain their energy
from primary consumers and tertiary consumers are organisms that obtain their energy from secondary
consumers. Secondary consumers are also called Carnivores or Omnivores. Carnivores eat meat only,
where as Omnivores eat both plants and meat. Tertiary consumers are usually found at the top of the
food chain. They eat Secondary Consumers. (Loxley et al (2010).
Food Chains and Food Webs
In order to study eco systems and habitats, it is important to have a sound understanding of food chains
and food webs. Food chains and food webs are not the same thing. Although they are interrelated they
are two different things. Food chains according to Oxford Dictionary is ‘the transfer of food energy from
plants through Herbivores to Carnivores’ (www.oxfordreference.com). For further clarification think
about this example: Grass (producer) feeds the grasshopper (primary consumer). Mice and rats
(secondary consumer) feed on the grasshoppers and the rats and mice are food for the hawk (tertiary
consumer). Food chains allow animals one path to find food. (Please refer to Appendix A).
Food webs according to Oxford Dictionary is ‘a system of food chains that are linked to one another’
(www.oxfordreference.com). Food webs can have several food chains interlinking into each other.
(Please refer to Appendix B)
All specimens play an important part in a food web and food chain. Some play more important roles
then others. Decomposers play a very important part in the food web. Without them the food web would
not exist and the eco systems would shut down and fail to work. (refer to Appendix A) As Loxley et al
(2010) states: ‘decomposers play a crucial role in food chains and food webs without them the eco
system would not function’ (pp. 157). Examples of decomposers include bacteria and fungi. Without
decomposers in the food chain and food web there would be no way to assist in the breaking down of
dead animals and plants-allowing the nutrients to return to the soil. Decomposers assist in the recycling of
nutrients allowing them to return to the soil (Loxley et al, (2010). Worms, slugs, snails can also be
considered as decomposers (Loxley et al, (2010).
When teaching children about food chains and food webs it is important to outline all the different and
unique specimens that make up food chains and food webs. Identify what is a producer and a
consumer. It is important to also inform students of what functions different organisms play in the
different food webs and food chains and to identify that all that contribute to the success of feeding
relationships.
Desirae Burger s1638736
Appendix A- An example of a Food Chain
http://3.bp.blogspot.com
Appendix B- Example of a Food Web
http://questgarden.com
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