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Course: Middle school biology - NGSS > Unit 5
Lesson 3: Activity: What happens when a food web is disturbed?Activity: What happens when a food web is disturbed?
Make science come alive in your classroom with this free hands-on activity aligned to middle school NGSS standards.
Activity: What happens when a food web is disturbed?
A polar bear trudges through a bleak landscape in the Arctic. There is nothing in sight except for ice. So, what does this polar bear eat to survive? The answer is found below the ice. Despite the cold, the Arctic is filled with life!
In this activity, students explore the Arctic marine food web in order to understand how energy and matter are transferred between different organisms. Students then use their understanding to hypothesize how the Arctic marine food web will change after a disturbance.
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Overview
This activity is designed to be completed in two 45-minute class periods, with additional time required for follow-up creative projects. The activity consists of the following parts:
- Setting the stage—Students read and demonstrate understanding of organisms found in the Arctic marine ecosystem and their roles in the food web. (10 minutes)
- Investigation (Part 1)—Students model the Arctic marine food web to illustrate the many connections of energy and matter from one organism to the next. (20 minutes)
- Investigation (Part 2)—Students learn about a disturbance to a food web. Students then predict how such a disturbance can impact the population size of different organisms. (15 minutes)
- Let's get creative!—Students research how climate change is affecting a focal organism from the Arctic marine food web. Students then imagine that they are leading a research team—they develop predictions and research questions about how climate change might disturb their focal organism and its connections to other organisms. (45 minutes)
- Keep creating!—Students can choose from additional project ideas. Each project encourages students to combine scientific knowledge with creativity to produce something new.
Printable resources
NGSS performance expectations
MS-LS2-3. Develop a model to describe the cycling of matter and flow of energy among living and nonliving parts of an ecosystem.
Related Khan Academy content
- Photosynthesis in ecosystems (video)
- Photosynthesis in ecosystems (article)
- Photosynthesis in ecosystems (understand exercise)
- Matter and energy in food webs (video)
- Matter and energy in food webs (article)
- Matter and energy in food webs (understand exercise)
- Matter and energy in food webs (apply exercise)
- Worked example: analyzing an ocean food web (video)
- Worked example: analyzing a generic food web (video)
Want to join the conversation?
i think we should start an online group for activities like this. so we all can better understand and submit our activity to the group.(28 votes)
Yas, definitely if this happens i will definitely join once I know what this is and its not scam(5 votes)
How do polar bears know when to go and get off the ice?(5 votes)
Polar bears are highly adapted to their Arctic environment and have developed various strategies to navigate their icy habitat. They typically rely on their keen senses, particularly their sense of smell, to detect changes in their surroundings.
As the seasons change and temperatures fluctuate, the ice conditions can vary significantly. Polar bears may be able to sense shifts in the ice, such as changes in thickness or stability, through vibrations or changes in scent patterns. They might also observe cues such as cracks forming or ice melting.
Additionally, polar bears are known to migrate seasonally, following the movement of sea ice as it expands and retreats. They often travel long distances in search of food, mating opportunities, or suitable habitat. This instinctual behavior helps them optimize their chances of survival in their harsh environment.
Overall, polar bears' ability to adapt to changing ice conditions is a combination of instinct, sensory perception, and learned behaviors passed down through generations.
Hope this helps!(7 votes)
- i think that is a great ideah(3 votes)
Is anyone here homeschooled?(3 votes)- Are polar bears primary consumers?(2 votes)
No! They are quaternary consumers or higher. A rabbit is a primary consumer.(3 votes)
- How can a polar bear survive in the coldness?(2 votes)
![hopper cool style avatar for user autumn :]](https://cdn.kastatic.org/images/avatars/svg/cs-hopper-cool.svg)
Polar bears could survive because of their thick, fuzzy and downy layer right next to their skin which would feel like wearing a wooly sweater, a layer of guard hairs or longer hairs, which acts like their raincoat and their 2 layers of fur help keep them warm even when the temperature is very cold. Hope this helps! :D(3 votes)
is there a third consumer?(3 votes)- Yes, a Tertiary consumer eats secondary consumers. For example, slugs, which are primary consumers, eat leaves, which are producers. A Robin, a secondary consumer, eats the slugs. Hawks, Tertiary consumers, eat birds.
Not AI generated. By me!(6 votes)
- I think if a ecosystem gets messed up a lot of animals would die and it would be messed up.(2 votes)
- Absolutely, you're correct. Ecosystems are delicate systems where each species plays a specific role, and they rely on a delicate balance to function properly. When disturbances occur, such as habitat destruction, pollution, climate change, or the introduction of invasive species, it can disrupt this balance and lead to cascading effects throughout the ecosystem. Great that you now understand that!(2 votes)
- is there a third consumer?(2 votes)
The third consumer is called the tertiary consumer; this type of consumer is not always present in every ecosystem, but it is usually there.(1 vote)
And what eats the demopster(1 vote)- Insects eat most kinds of fungi, and fungi, such as mushrooms are consumers, and humans eat mushrooms as well.
I hope this helps! :D(2 votes)