The Life Starter
Sign up
Grade 3 · lesson 1 of 4

Connect resources to populations

Connect resources to populations using supplied evidence and a solved model.

About 18 minutes, plus any extended practice

Download the grade pack

Supplied materials

  • All measurements and observations below are supplied classroom examples. They are not data from actual learners or a claim about a particular real site.
  • Paper, drawing space or a browser document.
  • Reference card A: not enough listed food. Reference card B: not enough listed water.
  • Assessment case 1: Which scientific label fits the specifically described step or feature? Supplied case: Only food supply falls.
  • Assessment case 2: Which scientific label fits the specifically described step or feature? Supplied case: Only drinking water disappears.
  • Assessment case 3: Which scientific label fits the specifically described step or feature? Supplied case: Only nesting area shrinks.
  • Assessment case 4: Which scientific label fits the specifically described step or feature? Supplied case: Only protective cover is removed.
  • Assessment case 5: Which scientific label fits the specifically described step or feature? Supplied case: Feeding resource decreases.
  • Assessment case 6: Which scientific label fits the specifically described step or feature? Supplied case: Available shelters vanish.

Learn the idea

Organisms require resources. Available food, water and space can limit a population. A resource change can affect more than one species, so a simple model is a starting point.

Food limit means not enough listed food. Water limit means not enough listed water. Space limit means not enough listed living space. Cover limit means not enough listed protection.

For food limit, look for the clue “not enough listed food.” For water limit, look for “not enough listed water.” More than one process can happen in a real situation. Answer about the one described in this question.

  1. Read or listen to the four science words and what each means. Say how the first two differ.
  2. Choose two of the short cases. Point to the clue that helps you choose a science word for each one. You may draw or say your answer.
  3. Answer each practice question. Say which clue helped you, then check the explanation.
  4. Use the extra task to make two examples that show different science words. Draw or say what makes each one fit.
Worked example

See the method in action

Worked reference-card problem: a card states “not enough listed food”; a second states “not enough listed water.” The first fits food limit and the second fits water limit. The reason is the described function or change, not the order of the cards or a favorite name. If their descriptions exchange places, their category labels exchange too. Keep the supplied descriptions attached to the correct case.

Your turn

Check your reasoning

Your answer is temporary and is not saved to an account. Download your current answer before leaving or reloading. Written work on paper or in another app stays in your own file.

Helpful tips
  • Use the feature “not enough listed food” to justify food limit; do not sort by the name alone.
  • Distinguish water limit (not enough listed water) from a different process occurring in the same situation.
Which scientific label fits the specifically described step or feature? Supplied case: Only food supply falls.

Feedback appears here after you check. This is practice, not a graded school assessment.

See the answer and explanation

food limit

The answer is food limit. In the notes, it means “not enough listed food.” Organisms require resources. Available food, water and space can limit a population. A resource change can affect more than one species, so a simple model is a starting point.

Take it further

Create one new case showing food limit and one showing water limit. Expected: the first explicitly shows “not enough listed food”; the second explicitly shows “not enough listed water.” Explain the distinction by drawing, speaking or writing. A label without a matching feature is incomplete.

Nothing here is saved to an account or sent to a teacher. The answer download includes your current choice and any checked feedback. It does not include choices from the separate More practice section. Download that section separately.

More practice: try new cases

Choose an answer for each problem. Explain your method on paper, then use the feedback to decide what to revisit.

More practice: try new cases
1. Which scientific label fits the specifically described step or feature? Supplied case: Only drinking water disappears.
Need a hint?
  • Look for the described feature: not enough listed water.
  • Compare the clue with each science word. Use only what the case tells you; do not add a new event.
2. Which scientific label fits the specifically described step or feature? Supplied case: Only nesting area shrinks.
Need a hint?
  • Look for the described feature: not enough listed living space.
  • Compare the clue with each science word. Use only what the case tells you; do not add a new event.
3. Which scientific label fits the specifically described step or feature? Supplied case: Only protective cover is removed.
Need a hint?
  • Look for the described feature: not enough listed protection.
  • Compare the clue with each science word. Use only what the case tells you; do not add a new event.

Your choices are temporary. Feedback appears after you check all the answers.

Nothing here is saved to an account or sent to a teacher. Keep your own notes or download them before leaving. The score describes these questions; it does not certify subject mastery.

Check the subject sources

These LifeStarter passages, scenarios and exercises are authored for this Academy with AI assistance and review. External resources keep their publishers’ terms. A grade label suggests a starting level; it does not establish alignment with your school’s complete requirements.