Energy Flow Food Chains and Food Webs
The main source of energy for any ecosystem is the SUN
SUN'S
________________. The ____________ energy is absorbed by PLANTS
______________ and is converted into a potential energy source ­ a FOOD
chemical potential energy source we call _____________. The name PHOTOSYNTHESIS
of this process is called ____________________________.
Scientists are always looking for patterns in nature. Many things about an ecosystem can be learned by looking at the patterns found in how organisms obtain their energy. Ecologists have devised food chains and food webs along with several descriptive terms to help understand an ecosystem. Match the following term with the correct definition
Carnivore
eats meat
Food Web
a community of organisms where there are several interrelated food chains Trophic Level a particular position occupied by a group of organisms in a food chain Consumer
needs to eat other organisms to get energy
Detritivore
any organism that eats decaying organic matter Herbivore
eats plants only
Producer
is able to make its own food through photosynthesis Food Chain
a community of organisms where each member is eaten in turn by another member Omnivore
eats both meat and plants
Food Chains
Food Chains show how organisms are linked together in an ecosystem based on what they ______________. The arrows in the food chain always point in the direction of the _______________ (ie. at the organism that is doing the eating).
1
Label the following food chain
Role and Order
Types of organisms
plants
grasshoppers
small birds
hawks
Trophic Level
Food Webs
In an ecosystem, many different ____________________ exist together creating a __________________________.
A __________________ shows the energy flow within an ecosystem starting with the ____________________ and ending with the __________________.
Label the following food web
Name 3 primary consumers.
What organisms are the top carnivores?
Draw one food chain that is within this food web.
What would happen if the herbivorous insects became extinct? Explain how this might effect other organisms in the food web.
2
Food Webs
How many organisms form the longest food chain in the food web?
Write this food chain out (make sure your arrows point in the right direction!)
Which organism in this food chain is 1. the top carnivore(s) (hint­ nothing eats the top carnivore)­ 2. a herbivore­ 3. a producer­ 4. at the 2nd trophic level­ 5. is a tertiary consumer­ Is there an omnivore in this food web?
List all the primary consumers in this food web.
If all the squirrels were killed by a virus, what would happen to this food web? Would it remain sustainable? Explain your answer in detail.
If a pack of coyotes entered this ecosystem, how would it be impacted? Explain your answer in detail.
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Food Chains and Food Webs Homework
Food Chains
Food chains show how organisms are connected through what they eat. The arrows in the chain always point in the direction the energy flows (towards the organism doing the eating). 1.
Using the organisms listed below draw a food chain in the box below. Your food chain should start with the producer and end with the organism that is not eaten by any other. Make sure your arrows are pointing in the direction of the energy flow. (leave space around your food chain to add labels)
grasshopper, mole, grass, owl
Level 2
Level 1
Level 3
2. Directly ABOVE (Level 1) the box label the following on your food chain:
producer(s)
consumer(s)
herbivore(s)
carnivore(s)
3. ABOVE (Level 2) the box label the following on your food chain:
1st trophic level
2nd trophic level
3rd trophic level
4th trophic level
The first consumer in the food chain is known as the primary consumer. The second consumer is known as the secondary consumer. The third consumer is known as the tertiary consumer.
4.
Directly BELOW (Level 3) the box label the following on your food chain: primary consumer, secondary consumer and tertiary consumer.
5.
Remember that we, as humans, are consumers. Below each of the following meals, draw the food chain from producer to you. Label each food chain fully.
a.
A salmon fillet (The salmon eats herbivorous fish)
.
b.
A steak
c.
A bowl of plain rice (think about what rice comes from!)
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