Web of Life Study Guide - Q3 Science Benchmark Flashcards
Give three examples of predator → prey relationships.
Possible answers: hawk eats a squirrel, snake eats a mouse, lizard eats a grasshopper
Give one example of a food chain with at least four links. Make sure you show how the energy is flowing through it by using arrows.
Possible answer: sun → grass → grasshopper → mouse → owl
Explain how a food web is different from a food chain.
A food web contains multiple food chains within one ecosystem. They both follow the flow of energy and materials between organisms.
Explain what happens when one organism in an ecosystem disappears. How does it affect the organisms that depended on it and how it affects the organisms it depended on?
When one organism disappears, the organisms that depend on it will struggle to survive because they lost their energy source. The organisms that it depends on will lose one of their predators, so their population will increase in size. For example, in this ecosystem food web: sun → grass → grasshopper → mouse → owl, let’s say the mouse population dies. The grasshopper population will increase, since there aren’t any mice hunting them, and the owl population will struggle, since they are losing the mice as one of their food sources. Hopefully, the organism depending on them will have more than one energy source.
Explain how a carnivore is dependent on plants, using your own words and making sure to include the words ENERGY.
Carnivores would go extinct without plants because they get their energy from the sun. Carnivores do not produce their own food or eat green plants, but the organisms that they eat get their energy from green plants. The energy can be traced back to the sun, which plants turn into energy for producers.
What is a producer? How does it get its energy? Give at least two examples.
Producers take in carbon dioxide and release oxygen. They include all green plants, algae, and phytoplankton. They get their energy from the sun and make their own food rather than eating other living things.
What is a consumer? How does it get its energy? Give at least two examples.
Consumers eat other organisms (plants or animals). They get their energy from those organisms, tracing that energy back to the sun. Some only eat plants (herbivores), some eat plants and animals (omnivores), and some only eat animals (carnivores). Possible examples include: mice, bees, snakes, birds, and wolves.
What are decomposers? Think about what they do, air, how they get their energy, examples of decomposers.
Decomposers break down waste and dead material into nutrients for plants. They get their energy from those dead plants and animals. They take in oxygen and release carbon dioxide. Examples: mold, mushrooms, bacteria, worms
How does a lack of decomposers affect an ecosystem?
Decomposers are necessary for an ecosystem to break down dead waste and dead material, so a lack of decomposers leads to a buildup of dead waste and dead material. This isn’t healthy for an ecosystem.
What are three things you learned about worms during our Worm Watcher experiment?
Possible answers: Worms live in the soil where it’s dark and damp, which is what they prefer. They can sense light and move away from the surface. Their bodies are soft and flexible, and can move forward and backward, which helps for moving through the soil.
Do plants need water, air, and nutrients equally to grow? If no, what do they need more of?
They do not need all three things equally. They rely on air primarily, then water, and last nutrients. Plants need sunlight for the process of photosynthesis but the materials they need for growth primarily come from water and air. Plants take in carbon dioxide from the air and convert it into glucose through the process of photosynthesis, which is powered by sunlight. Water supports the transportation of nutrients, from the soil up into the structures of the plant, is used in the process of photosynthesis, helps keep plants standing stiff and upright and not wilted or droopy, and water helps keep plants cool as it evaporates from the leaves.
Give another example of two living things that depend on one another. Explain their relationship and what each gets from the other.
Possible answers: A spider depends on a fly for energy. A rabbit depends on clover for both energy and air (it takes in the clover’s oxygen to breathe).
Which organisms were most likely to survive the Cretaceous extinction? Give a reason for each answer.
Small animals could survive on less energy, so they would be more likely to survive when food was scarce. Omnivores were more likely to survive because they could use many different sources of food, rather than depending on just one. Decomposers would have had lots of food sources from so many other animals dying. Plants would be more likely to survive than animals because they could use the small amounts of sun energy available, or survive as seeds!
