Limiting factors and carrying capacity

≈ 48 min

Limiting factors and carrying capacity

A limiting factor restricts population growth. Food, water, space, disease, predation and competition can be density-dependent: their effect grows as population density rises. Drought, fire or a temperature extreme can be density-independent. Carrying capacity is the approximate population size an environment can support over time, but it can change when rainfall, resources, habitat or human pressure changes.

Work it through

After good rains, grass increases and a herbivore population grows. As grazing pressure rises, food per animal falls and disease can spread more easily. The population may fluctuate around a changing carrying capacity rather than stop at one fixed number.

Mastery target

Classify a limiting factor and explain why carrying capacity is dynamic rather than a permanent ceiling.

Which factor is most likely density-dependent?

Spread of an infectious disease

A volcanic eruption

A sudden frost

A lightning strike

Name the key biological term from Limiting factors and carrying capacity: enter the term that best fits the explanation and visual model.

Why can carrying capacity change after a drought?

Less water and plant growth reduce available resources.

Every organism changes species.

The definition of population disappears.

Rain has no ecological effect.

Which statement corrects a common misunderstanding in Limiting factors and carrying capacity?

Correct: A population can temporarily exceed carrying capacity; the resulting resource shortage may later increase deaths or lower births.

A single observation is enough to prove every biological claim.

Scientific terms are interchangeable whenever they sound similar.

A process always has exactly the same result in every environment.