Abiotic / Biotic Factors & Adaptations

What is an abiotic factor?

A non-living factor in the environment.

Which abiotic factors can affect a community?

Light intensity -- Temperature -- Moisture levels -- Soil pH and mineral content -- Wind intensity and direction -- Carbon dioxide levels for plants --Oxygen levels for aquatic animals

How can light intensity affect plants?

Light intensity affects the rate of photosynthesis, which can affect plant growth and distribution.

How can temperature affect organisms?

Temperature affects the rate of enzyme-controlled reactions, which can affect growth, reproduction and survival.

How can soil moisture affect plants?

Plants require water for photosynthesis and other cellular processes, so water availability can affect their growth and distribution.

Why can soil pH affect plant distribution?

Soil pH affects the availability/uptake of mineral ions and different plant species have different optimum conditions.

Why does carbon dioxide concentration affect plants?

Carbon dioxide is required for photosynthesis.

Why does oxygen concentration affect aquatic animals?

Oxygen is required for aerobic respiration.

What is a biotic factor?

A living factor that affects a community.

Which biotic factors does AQA require you to know?

Availability of food -- New predators arriving -- New pathogens -- One species outcompeting another so numbers are no longer sufficient to breed

How can a new predator affect a community?

It may increase mortality of its prey, reducing the prey population, which can then affect other species through interdependence.

How can a new pathogen affect a population?

It may cause disease and death, reducing the population.

How can competition cause a species to disappear from an area?

Another species may outcompete it for limited resources, reducing its population until there are too few individuals to breed successfully.

What is an adaptation?

A feature that enables an organism to survive in the conditions in which it normally lives.

What are the three types of adaptation?

Structural, behavioural and functional.

What is a structural adaptation?

A feature of an organism's body structure that helps it survive. (Example: thick fur in a cold environment.)

What is a behavioural adaptation?

A way an organism behaves that helps it survive. (Example: migration.)

What is a functional adaptation?

A feature involving an organism's internal processes/functions that helps it survive. (Example: producing very concentrated urine to conserve water.)

What is an extremophile?

An organism adapted to live in extreme conditions, such as high temperature, pressure or salt concentration.

Give an example of an extremophile.

Bacteria living in deep-sea vents.