Environmental science summer exam 2025

What is an ecosystem?

All the living organisms in one area and also the physical environment.

Some examples can be deserts, marine and tropical rainforest ecosystems.

What does habitat mean?

Where a particular organism lives.

What does population mean?

The total number of one species.

What does community mean?

All the populations interacting together.

What is an abiotic factor?

It is a factor in an ecosystem that is not alive.

This could be the temperature, rainfall or humidity.

What is a biotic factor?

It is a factor in an ecosystem that is alive.

This could be an animal, fungi or plants.

What is a producer?

An organism that makes its own food (like plants make their own food through photosynthesis).

What is a consumer?

An organism that gains nutrition by eating other organisms (predators and prey).

What is a predator?

An organism that hunts prey.

Foxes

What is prey?

An organism that is predated.

Rabbits

What is a herbivore?

An organism that only eats plants.

Rabbits

What is a carnivore?

An organism that only eats animals.

Foxes

What is a decomposer?

A decomposer is an organism that decomposes, or breaks down, organic material such as the remains of dead organisms. This includes bacteria and fungi.

What is the original source of energy in a food chain?

The sun/sunlight. The arrows show the flow of energy in a food chain.

Why do we use sampling to estimate population of plants and invertebrates in an area?

To get a rough estimate without needing to count every individual.

Describe some simple techniques for invertebrate sampling?

You could use sweep nets which are used for collecting insects and other small animals from bushes and ponds.

You could use a pooter which is a small jar for collecting insects. It has two tubes.

What are some abiotic factors that might influence the distribution of plant species?

1. Where the sun is/ the light intensity

2. Soil moisture

3. How much trampling has occurred

What is meant by the term classification?

The grouping together of organisms according to observable similarities.

Give some examples of classification groups?

Plants, animals, vertebrates and invertebrates.

How does acid rain form?

Fossil fuels are burnt in power stations and they contain sulphur or nitrogen etc. When this is burned with oxygen it produces sulphur dioxide/nitrogen oxide. When these are dissolved in water they make nitric/sulfuric acid.

What are some effects of acid rain?

• Can damage statues or buildings due to it being corrosive.

• impacts on forests, freshwaters, soils, microbes, insects, and aquatic life-forms.

• Respiratory issues in animals and humans.