Ecosystems

What is an ecosystem?

An area in which all living organisms and non-living physical factors form a stable relationship.

What is a population?

A group of the same species that live in a particular area.

What is a community?

All the different organisms that live in a particular area and interact with each other.

What is a habitat?

The area in which an organism or population lives.

What does interdependent mean?

When two organisms are dependent on each other.

What is the order of the food chain (top down)?

• Apex predator

• Tertiary consumer

• Secondary consumer

• Primary consumer

• Producer

What do producers produce?

Biomass:

• Starch

• Cellulose

• Sugars

• Proteins

• Fats

What are abiotic factors?

Non-living factors that affect an ecosystem.

What are some examples of abiotic factors?

• Rainfall

• Light

• Space

• Altitude

• Salinity

• Wind

• Temperature

What is abundance?

A measure of how plentiful something is.

What is a food web?

A diagram of interlinked food chains that shows interdependent feeding relationships.

What is a quadrat?

A square frame of known size used to get a sample of the organisms living in that area.

What is a resource?

Something that an organism needs in order to stay alive.

What is drought?

A prolonged period of lower rainfall, leading to a water shortage.

How would drought kill off land plants?

Their roots can’t stay submerged for long, and they wouldn’t be able to photosynthesise.

What is competition between species?

When resources are limited and species have to fight for them.

What are biotic factors?

Living things that affect other living things.

What are some examples of biotic factors?

• Parasitism

• Disease

• Predation

• Prey availability

What do the arrows in a food web show?

The direction that energy is travelling.

What is parasitism?

The relationship where one organism benefits by feeding off of another, causing harm to it.

What are some tapeworm adaptations?

• Hooks and suckers to attach firmly to the intestine wall.

• Contains both male and female sex organs so fertilisation can occur.

• Its flattened body allows absorption of nutrients across its surface without a digestive system.

What are some head louse adaptations?

• Sharp mouthparts to pierce skin and suck blood.

• Sharp claws to grip onto hair and skin.

• Eggs are glued to hairs to prevent them from falling off.

What is a mutualistic relationship?

When both organisms involved benefit each other while also benefitting.

What are some examples of humans affecting biodiversity?

• Poaching/hunting

• Adding plastic to seas/oceans

• Deforestation

• Littering

• Urbanisation

• Animal testing

• Landfill

• Releasing greenhouse gases

What are some advantages of fish farming?

• Overfishing is reduced

• Fish are easier to catch

• Fish will be bigger as they’re eating more and swimming less

• Fish are protected from predators and disease

What are some disadvantages of fish farming?

• It’s not ethical for the fish

• Disease can be transferred easily and quickly

• There will be lots of waste building up in the water

• It can be expensive

What is a native/indigenous organism?

Organisms that have always been in an area.

What is a non-indigenous organism?

An organism that has been introduced into an area, and hasn’t always lived there.

What is eutrophication?

The addition of extra nutrients to an ecosystem.

What is the journey of fertiliser?

• It’s added to a field.

• Heavy rain washes it off and nitrates and phosphates dissolve in the soil water.

• Leftover nitrates and phosphates are washed into streams or rivers, which encourages plants and algae to grow rapidly.

• Surface plants block sunlight, so plants in the water die and stop photosynthesising.

• Decomposers increase and use up more oxygen from the water.

• The oxygen concentration of the water decreases and aquatic animals die due to the lack of it.

What is conservation?

The protection of a rare/endangered species of habitat to prevent damage and maintain biodiversity.