Ecosystem Factors ILEARN Quiz
ILEARN BIOLOGY Indiana Assessment Practice • Quick Check
Standard: LS.2 / B.2.1 (Ecosystem Interactions)
Student Name:
Date:
Period:
Score: / 4
Directions: Read each science description carefully. Answer the questions by checking the correct table boxes or choosing the best answer option.
QUESTION 1 Classification Table
A biology class visits a wetland next to the Wabash River. Students make a list of parts found in the habitat. Decide whether each item is a biotic factor (living or once-living) or an abiotic factor (non-living). Place a checkmark (✓) in the correct column for each row.
| Habitat Observation / Item | Biotic Factor
(Living / Once-living) | Abiotic Factor
(Non-living) |
| --- | --- | --- |
| Nutrients (nitrogen and phosphorus minerals) dissolved in the river water |
|
|
| Fungi growing on the roots of willow trees to help them absorb water |
|
|
| Amount of sunlight shining through the tree leaves onto the water |
|
|
| Dead leaves and decaying wood breaking down in the wetland mud |
|
|
QUESTION 2 Environmental Changes
Field Story: Acid rain falls on an Indiana forest for several years, making the soil much more acidic. This acidic soil washes away healthy minerals that trees need and releases harmful aluminum into the ground. Over the next two years, 65% of the young maple trees die.
Which statement best explains how this change in an abiotic factor affects the living (biotic) parts of the forest?
A The damaged soil limits plant growth, which means less food and energy will be available for the forest animals. B The trees die because plant-eating animals turn into decomposers and eat the acidic minerals instead of plants. C The acidic soil only harms animals, leaving all forest plants completely unaffected because plants only need sunlight. D Losing minerals from the soil helps the forest by allowing new trees to grow much faster without any competition.
ILEARN Practice Item Set • Interdependent Ecosystem Dynamics Go on to the next page → Page 1 of 2
ILEARN BIOLOGY ASSESSMENT • SECTION 2: DATA CLUSTER
Student Name:
Cluster Information: Lake Temperature and Fish Data Table
During late July, scientists tested the water conditions at different depths in an Indiana lake. Brook trout are a type of fish that need cool water and oxygen to survive.
| Lake Depth Zone | Water Temp. | Dissolved Oxygen (for breathing) | Trout Found |
|---|
| Surface Layer (0–3 meters) | 26.2°C (Warm) | 8.5 mg/L (High) | 0 |
| Middle Layer (4–7 meters) | 13.5°C (Cool) | 7.4 mg/L (Good) | 46 |
| Deep Bottom Layer (8–12 meters) | 8.0°C (Cold) | 1.5 mg/L (Very Low) | 1 |
QUESTION 3 Part A
Based on the data table, which statement best explains why most trout live in the middle layer of the lake?
A Trout need a balance of abiotic factors: water that is cool enough for their bodies and has enough dissolved oxygen for them to breathe. B Trout live in the middle layer only to hide from predators, and abiotic water temperature does not matter to them. C The fish warm up the lake surface with their bodies and push all the oxygen down into the deeper water. D Dissolved oxygen is an abiotic factor that fish do not need as long as they stay at the bottom of the lake.
QUESTION 4 Part B: Evidence Selection
Which evidence from the data table best supports the answer to Question 3 (Part A)?
A Trout avoid the surface because the water is too warm (26.2°C), and they avoid the bottom because there is not enough oxygen (1.5 mg/L). B Trout prefer the warm surface water because warm water always holds the most oxygen for fish to breathe. C Trout are spread equally across all three depths because abiotic conditions do not change in different layers of the lake. D The deep bottom layer has 46 trout because low oxygen helps fish swim faster and survive longer.
STOP
You have completed all questions in this set. Review your answers before turning in your paper.
Indiana Assessment System • Biology Cluster Check Page 2 of 2
