Communities in Ecosystems

A single living thing.

A group of similar organisms that can breed together to produce fertile offspring.

All the organisms of one species living in an area.

All the populations of different species living in an area.

A community and its non-living surroundings.

The place where an organism lives.

The ecosystem.

A population.

Organism, population, community, ecosystem.

All the sticklebacks.

All the plants and animals living in it.

The water, light or temperature.

Yes, for example a puddle or a rotting log.

One.

Each species has its own habitat and role.

Name the level of organisation marked X.

A community. It is all the populations of different species living in an area.

Describe each level of organisation.

Organism: one living thing. Population: all the organisms of one species in an area. Community: all the populations of different species in an area. Ecosystem: the community and its non-living surroundings.

The non-living factors in an ecosystem.

The living factors in an ecosystem.

Temperature, light intensity, moisture level and soil pH.

Predators, food and disease.

They need light for photosynthesis.

It changes how well the roots take up minerals, so it decides which plants grow.

The population of the prey falls.

It falls.

To sample the organisms in a small area.

A line along which samples are taken to see how species change.

With a light meter.

With a pH probe or indicator.

To get a reliable mean that represents the whole area.

No, other factors could also be involved.

Light reaches the woodland floor before the trees grow leaves.

Sort these factors into abiotic and biotic.

Abiotic (non-living): light intensity, temperature, moisture level, soil pH. Biotic (living): predators, food, disease, competition.

Species in a community depending on each other.

A predator hunting and eating its prey.

An interaction in which both organisms benefit.

Nitrogen-fixing bacteria in the root nodules of clover.

A parasite living on or in a host and feeding on it, which harms the host.

A tapeworm, a tick or a flea.

Light, water, mineral ions and space.

Food, water, mates, shelter and territory.

The prey population falls.

The prey.

The predators need the extra prey to reproduce and grow.

One where the populations stay fairly constant.

The species that depend on it are affected.

The parasite.

No, both are harmed, because they need the same resource.

Name the type of interaction and say who benefits.

Predation: the predator benefits and the prey is harmed. Competition: both are harmed. Mutualism: both benefit. Parasitism: the parasite benefits and the host is harmed.

The position of an organism in a food chain.

Producers.

An animal that eats producers.

An animal that eats primary consumers.

The direction in which biomass is transferred.

The mass of living material at each trophic level.

One large organism can have a huge biomass but count as one.

Parts not eaten, egestion, excretion and respiration.

The loss of undigested food as faeces.

The loss of waste substances such as urea.

The carbon is lost as carbon dioxide, and the energy is released.

Biomass transferred divided by biomass available, times 100.

About 10 per cent.

So much biomass is lost at each step that there is too little left at the top.

Fewer trophic levels, so less biomass is lost.

Name the trophic level marked X.

The secondary consumer, trophic level 3. It eats the primary consumer, the caterpillar.

Label each level of this pyramid and say what it shows.

From the bottom: producers, primary consumers, secondary consumers, tertiary consumers. It shows the mass of living material, the biomass, at each trophic level, which gets smaller at each step.