Biotic or Abiotic?
A mushroom is growing beside a rock. Classify the mushroom and rock.
Mushroom = biotic; rock = abiotic.
Give one way a plant depends on an abiotic factor.
Examples: sunlight for energy; water; air/CO₂; soil/nutrients.
Name two resources an animal might need.
Food, water, oxygen/air, space/shelter; appropriate examples accepted.
There are 5 birds and plenty of seeds. Is food abundant or scarce?
Abundant/plentiful.
Complete the pattern: Resource ↓ therefore, availability ______.
Decreases.
A dead tree is standing in a forest. A student says it became abiotic when it died. Is the student correct? Explain.
No. The tree remains biotic because it was once living.
A pond loses much of its water. Name one biotic factor that could be affected and explain how.
Answers vary; e.g., fish may have less habitat/water available.
A plant has water and sunlight but very little space to grow. Can space be a resource? Explain.
Yes. Space is a resource organisms may need to survive/grow/reproduce.
A habitat has 10 deer and enough food for them. The food stays the same, but the deer population grows to 30. What happened to food availability for each deer?
It decreased/became more limited because more deer share the same amount.
A lake's fish population stays the same, but the amount of food available decreases. Predict one possible effect on the fish.
Some may not obtain enough food; growth/reproduction/survival may decrease or some may leave, depending on context.
A pond contains fish, algae, water, rocks and sunlight. Identify two biotic and two abiotic factors and explain the rule you used.
Fish/algae = biotic; water/rocks/sunlight = abiotic. Biotic factors are living or once living; abiotic factors are nonliving.
Why isn't an ecosystem simply a list of living and nonliving things?
Because the living and nonliving components interact/depend on one another.
A rabbit has plenty of water but almost no food. Does having one abundant resource mean the rabbit has everything it needs? Explain.
No. Organisms require multiple resources; one needed resource can still be limited.
Two forests contain exactly 100 berries. Forest A has 10 bears; Forest B has 30 bears. Explain why the same quantity of berries can represent different resource availability.
More organisms need the berries in Forest B, so fewer berries are available per bear; availability depends on both resources and organisms needing them.
A student says: “Resource availability only changes when resources disappear.” Use evidence from what we learned to prove the student wrong.
Availability can also decrease when the number of organisms increases while the resource amount stays the same, because more organisms must share the same resource.