Ecosystems Flashcards
What is the definition of biodiversity?
The range of species within an ecosystem.
What is the definition of species?
A group of organisms which can interbreed and produce fertile offspring.
What is meant by population?
The total number of living organisms of one type (species) living in a habitat.
What is meant by a habitat?
The place where an organism lives e.g. in water, in soil, trees etc.
What is meant by a community?
All the organisms e.g. plants, animals and micro-organisms, that live in a particular area.
What is meant by an ecosystem?
All the organisms (the community) living in a particular habitat and the non-living components with which the organisms interact.
sometimes written as community + habitat.
Describe what is meant by a niche.
Every organism has its own niche. A niche is the role an organism plays within a community. It relates to the resources it requires in its ecosystem, such as light and nutrient availability and its interactions with other organisms in the community. It involves competition and predation and the conditions it can tolerate e.g. temperature.
What is the definition for a niche?
The role an organism plays in the community.
What is the definition for a producer?
An organism that can produce its own food. e.g. a plant
What is the definition for a carnivore?
An animal which eats only animals.
What is the definition for a consumer?
An animal which eats other organisms.
What is the definition for a herbivore?
An animal which eats only plants.
What is the definition of a predator?
An animal that hunts and eats other animals.
What is the definition of prey.
An animal that is hunted and eaten by other animals.
What is the definition of a decomposer?
An organism which feeds on dead organisms.
What is the definition of an omnivore?
An animal which eats plants and animals.
What is a food chain?
A food chain is a diagram which shows a simple feeding relationship between organisms.
How is a food web made?
A series of interconnecting food chains make up a food web which shows the detailed feeding relationships between organisms (of different species) in an ecosystem.
Do food chains exist in isolation?
Food chains rarely exist in isolation.
What do the arrows in a food web represent?
The arrows in a food web point from the food to the feeder and represent the flow of energy from one organism to another.
What do food webs always start with?
Food webs always start with a producer, this is a plant.
What can disrupt a food web?
Food webs are delicately balanced and the removal of one organism (species) can affect all the other organisms (species) in the food web. Human activities such as hunting, fishing or using chemicals that cause pollution, can all disrupt a food web.
When does competition in ecosystems occur?
Competition in ecosystems occurs when recources are in short supply e.g. food, light (plants), water, mates, habitat.
What are the effects of competition?
The effects of competition include more individuals of the successful species surviving to reproduce, thus increasing the number of successful species. The less successful species may therefore decrease in number.
