How does competition act as a biotic factor in an ecosystem?

Competition between organisms for limited resources affects their distribution and abundance, as individuals that compete less successfully may be excluded from areas or have reduced survival.

How does temperature act as an abiotic factor affecting organisms?

Temperature affects the distribution and abundance of organisms by influencing metabolic rates and determining which species can survive in a given area.

How does light intensity function as an abiotic factor?

Light intensity affects the distribution and abundance of organisms, particularly plants, by determining the rate of photosynthesis and where autotrophs can thrive.

How does the concept of niche explain the distribution of organisms?

Organisms are found only where environmental conditions match their niche requirements.

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Biotic and abiotic factors, niches and competition

3 things to know
Papers 1 and 3

Overview

Recall questions on the factors that shape where organisms live, the ecological niche, and the competitive exclusion principle.

What you need to know

Answer each one before you reveal it.

Your recallNot started

Process

How does the concept of niche explain the abundance of organisms?

Key term

How can disease function as a biotic factor?

Key term

What are abiotic factors?

Questions from this subtopic

Each one with the model answer underneath.

1
How does competition act as a biotic factor in an ecosystem?
Model answer
Competition between organisms for limited resources affects their distribution and abundance, as individuals that compete less successfully may be excluded from areas or have reduced survival.
2
How can disease function as a biotic factor?
Model answer
Disease affects the distribution and abundance of organisms by reducing population numbers and potentially eliminating species from certain areas.
3
What are abiotic factors?
Model answer
Non-living physical and chemical components of an ecosystem that affect the distribution and abundance of organisms.
4
How does temperature act as an abiotic factor affecting organisms?
Model answer
Temperature affects the distribution and abundance of organisms by influencing metabolic rates and determining which species can survive in a given area.
5
How does light intensity function as an abiotic factor?
Model answer
Light intensity affects the distribution and abundance of organisms, particularly plants, by determining the rate of photosynthesis and where autotrophs can thrive.
6
How does the concept of niche explain the distribution of organisms?
Model answer
Organisms are found only where environmental conditions match their niche requirements.

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