Practice Flashcards
Flip to reveal answersWhat is a stable ecosystem?
Track your progress — Sign up free to save your progress and get smart review reminders based on spaced repetition.
All 9 Flashcards — What makes an ecosystem stable
Sign up free to track progress and get spaced-repetition review schedules.
Question
What is a stable ecosystem?
Answer
One that **stays roughly the same over time** and **returns to balance after a disturbance**.
Question
Why is stability called an 'emergent property'?
Answer
It belongs to the **whole ecosystem working together**, not to any single organism — it emerges only at the level of the whole system.
Question
What is resilience (of an ecosystem)?
Answer
The ability to **recover and return to its normal state** after a disturbance.
Question
List the four requirements for a stable ecosystem.
Answer
**1)** a continuous supply of energy, **2)** recycling of nutrients, **3)** genetic diversity within populations, **4)** steady climatic/abiotic variables.
Question
Why must energy be continuously supplied to an ecosystem?
Answer
Energy is **lost as heat** at each trophic level and **cannot be recycled**, so it must keep coming in (as sunlight).
Question
Why are nutrients recycled rather than constantly resupplied?
Answer
The chemical elements (C, N, P) are **finite**, so **decomposers return them** to the soil/water for producers to reuse.
Question
Why does genetic diversity help keep an ecosystem stable?
Answer
Variation means **some individuals survive** a new disease or stress, so a whole population is **not wiped out** by one change.
Question
Why does high biodiversity make an ecosystem more resilient?
Answer
Species have **overlapping roles**, so if one is lost **another can fill the role** — the web is not broken and the ecosystem returns to balance.
Question
In one line: how do energy and nutrients move through an ecosystem?
Answer
**Energy flows through** (lost as heat); **matter/nutrients cycle round** (recycled).
Read the notes
Full study notes for What makes an ecosystem stable
Topic 4.11 hub
Stability and change
More from Topic 4.11
All flashcards in this topic
Biology exam skills
Paper structures & tips
Track your progress with spaced repetition
Sign up free — Aimnova tells you exactly which cards to review and when, so you remember everything before your IB exam.
Start Free