Angela's Tools · Chapter 20 · Resources in Living Systems
Worksheet 2 of 10
Resource, Condition or Competitor? Sorting the Words of a Pond
Learning target: I can tell resources apart from conditions, sort resources as living or nonliving, and use the terms population, competition, limiting resource, carrying capacity, ecosystem and biosphere correctly in new situations.
Vocabulary in actionAbout 30 minIndividual
MS-LS2-1 · supportsMS-LS2-2 · supports
independent practicewriting
NameDatePeriod
Directions
Read the word list first. Every task on this sheet asks you to use the relationships between the words, not just their definitions. A quick test you will use often: a resource is something an organism takes in or uses up (so there can be less of it for others); a condition is something an organism experiences but cannot use up, like temperature. Work alone, then compare Part A with a partner before you go on.
You will need: This worksheet, Pencil
- resource
- Any material, energy or space a living thing takes in or uses in order to stay alive, grow and reproduce. Food, water, oxygen, light, soil nutrients and nesting space are all resources.
- biotic resource
- A resource that is, or comes from, a living thing: the grass a deer eats, the insects a frog eats, the dead leaves a snail scrapes up.
- abiotic resource
- A resource that is not alive: water, oxygen, carbon dioxide, sunlight, minerals in the soil, a space to nest.
- condition
- A feature of the environment that affects organisms but is not used up by them, such as temperature, how fast water flows, or how acidic the water is. Conditions decide where an organism can live, but they are not resources.
- limiting resource
- The resource that runs short first. When a population grows until there is not enough of one resource to go around, that resource sets the limit on how large the population can get.
- carrying capacity
- The largest number of members of one species that an area's resources can keep supporting over time. It changes when the supply of the limiting resource changes.
- competition
- An interaction in which two or more organisms need the same limited resource, so whatever one takes leaves less for the others. It happens within a species and between species.
- organism
- One individual living thing: a single heron, a single snail, a single cattail plant.
- species
- A group of similar organisms whose members can breed with one another and produce offspring that can also reproduce.
- population
- All the members of one species that live in the same area at the same time, such as all the bullfrogs in one pond.
- ecosystem
- All the populations in an area together with the nonliving things (water, soil, air, light) that they depend on and interact with.
- biome
- A very large region of Earth, on land or in water, with a particular set of conditions and resources and the kinds of living things those support, such as a tropical rainforest or a temperate grassland.
- biosphere
- Every part of Earth where life exists, from the deep ocean floor to the air above the highest peaks: all of Earth's ecosystems together.
Part A: Sort the pond
Twelve things from a farm pond are listed in the table. Decide whether each one is a biotic resource, an abiotic resource, or a condition (not a resource). Write a check mark in one column for each row. Then, in the last column, write the name of one pond organism that uses it (for resources) or is affected by it (for conditions).
1.Sort each item and name one organism that uses it or is affected by it.
| Biotic resource | Abiotic resource | Condition (not a resource) | Who uses it or feels it? |
|---|
| Sunlight reaching the pond surface | | | |
| Water temperature in July | | | |
| Algae that snails scrape off rocks | | | |
| Oxygen dissolved in the water | | | |
| Nitrogen compounds in the mud | | | |
| Mosquito larvae eaten by minnows | | | |
| How acidic the water is (its pH) | | | |
| Space along the bank for frog egg masses | | | |
| Minnows caught by a heron | | | |
| Dead leaves eaten by shredder insects | | | |
| Carbon dioxide used by water plants | | | |
| How fast water flows in from the creek | | | |
Part B: Fill the levels
2a.The second level (between organism and ecosystem) is called a ________. Write the word and then define it in one sentence using the pond.
2b.The largest level is called the ________. Write the word and then give one reason it must include the air above the pond.
3.Many scientists add a level called a community between population and ecosystem. Using the definitions in the word list, what must a community include that a population does not, and what must an ecosystem include that a community does not?
Part C: Which word fits?
4.Write the one vocabulary word that best names each description. Each word is used at most once.
| Vocabulary word |
|---|
| All the bullfrogs living in one pond |
| Two minnows dart toward the same mosquito larva |
| The water plants grew fast until the phosphorus in the mud was used up, and then stopped |
| The number of bullfrogs this pond can keep supporting year after year |
| A single great blue heron standing in the shallows |
| Every pond, prairie, forest and ocean on Earth, with everything that lives in them |
| The pond's water, mud, air and light together with every population living there |
| A huge region with long cold winters, little rain, and low plants but no trees |
Part D: Use the words in a new place
5.Snails and tadpoles in the pond both scrape algae off rocks. Name the interaction between them, name the resource, and explain whether this is competition within a species or between species.
6.A kelp forest off the California coast has kelp (a large seaweed), sea urchins that eat kelp, sea otters that eat urchins, sunlight, and nutrients in the seawater. Write three sentences about the kelp forest. Each sentence must use two vocabulary words correctly. Underline the vocabulary words.
7.Explain the difference between a limiting resource and a carrying capacity using the pond's bullfrogs. Your answer must say which one is a thing and which one is a number.
8.Bullfrogs live in thousands of ponds across North America. Explain why 'the bullfrogs in Miller's pond' is a population but 'bullfrogs' by itself is a species, not a population.
The 'used up?' test and a word bank
For Part A ask two questions in order. (1) Can organisms use it up, so that there is less for others? If no, it is a condition. If yes, it is a resource. (2) Is it alive, or did it come from something alive? If yes, biotic; if no, abiotic. For Part C, the eight words you need are: organism, population, ecosystem, biome, biosphere, competition, limiting resource, carrying capacity. Cross each one out as you use it.
Your own resources and conditions
Make the same three-column sort for a human being living in a desert city: list at least four biotic resources, four abiotic resources, and three conditions. Then decide which single resource would most likely become the limiting resource for the city's population if the city kept growing, and write a paragraph defending your choice. Finish by explaining how the city's carrying capacity could rise without the resource itself increasing (for example, by using it more efficiently).