Name _______________________________________________________ Date __________________ Period ______
Bill Nye the Science Guy – Food Webs
1. What is today’s show all about?!? Food Webs!
2. Defend this statement with an explanation: All living things depend on plants.
Either you ARE a plant, you EAT plants, or you EAT things that EAT plants!
3. A _____food web__________ shows the many connections/feeding relationships within an environment.
4. How are you connected to CORN just by eating a chicken sandwich?
The chicken sandwich has chicken, which eats corn.
5. Describe decomposers.
Break down dead things and return the nutrients to the soil.
a. Identify the three examples of decomposers given by Alfonso.
Fungi, worms and bacteria.
b. Why are decomposers so important within an ecosystem?
They recycle nutrients to the ecosystem so that they can be used again and again.
6. A majority of the plants on Earth can be found in the _____ocean________.
a. Why is this such a good location for plants to grow?
Plenty of sunlight, water and nutrients – great for photosynthesis! No need to worry about wind.
7. Describe the experiment done by the two kids in order to conclude that plants need light to grow!
They grew an onion beside a window and grew another in a dark closet. The onion by the window started
sprouting, while the onion in the closet did not.
8. One could argue that all living things ultimately depend on the ______sun_________ (not plants!).
a. List the three things plants need to make their own food.
Sunlight, water and carbon dioxide.
b. The process of plants making their own food is known as PHOTOSYNTHESIS! What does
“photosynthesis” actually mean?
“making from light”
9. In terms of gas exchange (oxygen and carbon dioxide), draw a picture in the space below to show the
connection between plants and animals.
PLANTS
oxygen
Carbon dioxide
ANIMALS
10. Horticulturists, such as those working at Epcot in Disney World, use a process known as
_____hydroponics________________ in order to grow plants in locations other than soil.
11. Defend this statement with an explanation: Without the bottom of a food chain, the top can’t survive.
If a trophic level disappears, the organisms that eat them will also be affected.
12. The food web is based on a food/energy pyramid! There are lots of ______producers/autotrophs__________ at
the base of an energy pyramid.
a. Why are they found at the bottom?
There are a lot of them & they have the most energy available to them (they get energy from the sun!)
b. As you travel up the food/energy pyramid, there is ( more / less ) energy to go around.
Analysis questions:
13. Circle the correct answer. All ecosystems exist on a foundation built on
a. Carnivores
b. Autotrophs
c. Herbivores
d. Omnivores
14. The arrows of food chains and food webs represent the flow of _____energy_____ through an ecosystem.
15. Study the energy pyramid seen to the right.
a. According to the diagram, what
percentage of energy is PASSED ON from
one trophic level to the next? 10%
b. Therefore, what percentage of energy is
LOST from one trophic level to the next?
90%
c. Which organism would you expect to be
the most abundant in this ecosystem?
Grass
d. Which organism would you expect to find
the least number of in this ecosystem?
Hawk
e. Provide an explanation for why there are less top predators than producers.
There is less energy available to them