Biology - Ecology, Ecosystems and Biodiversity

What is ecology ?

The study of the interactions between living things (organisms) and between living things and their environment

What is the biosphere ?

The part of the planet where life can exist

What is an ecosystem ?

A group of clearly distinguished organisms that interact with their environment as a unit

What are examples of ecosystems ?

Woodlands, grasslands, bogs, lakes, sand dune systems, salt marshes, rocky seashores and hedgerows

What is a population ?

All the members of the same species living in an area

What is a community ?

All the different populations in an area

What is a habitat ?

The place where an organism lives

What is biodiversity ?

The variety of life that exists in a specified area

What are the three levels of biodiversity ?

Species, genetic and ecosystem diversity

What factors are responsible for biodiversity loss ?

Changes in land use causing loss of habitats

Overexploitation

Pollution

Climate change

Invasive species

What are benefits of some human activities on the diversity of species ?

Conservation areas

Interventions

Sustainable farming

Sustainable fishing

Breeding programmes

Rewilding

What are disadvantages of some human activities on the diversity of species ?

Deforestation

Overpopulation

Climate change

Pollution

Overexploitation

Invasive species

What is conservation ?

The wise management of the environment (or preservation or protection) in order to maintain biodiversity and prevent extinctions

What are the benefits of conservation ?

It limits the loss of biodiversity

It prevents organisms from becoming extinct

It maintains the balance of nature

Organisms may be found to be useful in the future

Organisms and habitats are enjoyable to see and visit

We have no right to wipe out other life forms

What is the carrying capacity of an ecosystem ?

The maximum population size that can be supported by the available resources in the ecosystem

What does abiotic mean ?

Non-living

What does biotic mean ?

Living

What are examples of abiotic factors ?

Water, oxygen, space, temperature and soil

What are examples of biotic factors ?

Food, disease, competition and predation

What is competition ?

An active struggle between organisms for a resource that is in short supply

What is predation ?

The killing and eating of an organism from another species

What is a predator ?

An organism that kills and eats

What is a prey ?

The organism that is killed and eaten

What is the primary source of energy for our planet ?

The sun

How is energy lost when organisms feed on each other ?

As heat, uneaten parts and waste products

What are producers ?

Organisms that make their own food by carrying out photosynthesis

What are flora ?

All the plants in an ecosystem

What are consumers ?

Organisms that take in food from another organism

What are fauna ?

All the animals in an ecosystem

What are the primary consumers ?

Herbivores, decomposers and detritus feeders

What are decomposers ?

Organisms that feed on dead organic matter, for e.g. bacteria and fungi

What are detritus feeders ?

Organisms that feed on small parts of dead and decomposing plants and animals, for e.g. earthworms and woodlice

What are the secondary consumers ?

Carnivores, scavengers, tertiary consumers and omnivores

What are scavengers ?

Animals that feed on animals killed by other sources for e.g. foxes, crows and seagulls

What is a food chain ?

A sequence of organisms showing the transfer of energy from one organism to the next

What is energy flow ?

The transfer of energy from one organism to the next in the food chain

What is a trophic level ?

A feeding stage in a food chain

What is a tertiary consumer ?

If no other organism feeds on them, then that consumer is called a top consumer

What is the percent of energy in each trophic level that is passed on to the next ?

10 percent

What is a food web ?

Consists of two or more interlinked food chains

What does a pyramid of numbers represent ?

The number of organisms at each trophic level