Life on earth Flashcards
Definition of species
A group of organisms that are able to interbreed to produce fertile offspring of a similar type
Definition of biodiversity
the variety and abundance of living organism found in a particular area
Definition of population
the number of individuals of one species found in an area
Definition of producers
green plants that can produce food by the process of photosynthesis
Definition of consumer
consumers eat other organisms to obtain energy
definition of herbivore
A consumer that only eats plants to obtain energy
Definition of carnivore
only eat other animals to obtain energy
Definition of omnivore
consumers that eat both animals and plants to obtain energy
Definition of predator
consumers that kill other animals to eat
Definition of prey
Species that ate killed by other consumers
Definition of food chain
a sequence of organisms through which energy flows when one organism eats another
Definition of food web
Shows the numerous paths that energy can take as it flows through the species in an ecosystem
What is an ecosystem
An ecosystem consists of all the organisms living in a particular habitat and the non living components which these organism interact
What does a food web show
The feeding interactions within a food web using arrows to show the direction of energy flow which indicates which species are feeding on which as the energy moves from prey to predators
What do food webs also reveal
Competitive interactions within a food web
What is the effect on a food web if a prey species is removed
It’s predators will decline in population
What is the effect on a food web if a predator species is removed
It’s prey species will become more common
What is a niche
A role that an organism plays within a community
What does a niche relate to
the resources an organism requires in its ecosystem, such as light and nutrient availability, and its interactions with other organisms in the community
What does niche involve
competition and predation and the conditions an organism can tolerate, such as temperature
When does competition in ecosystems occur
When resources are in short supply
Does interspecific competition occur between the same species or different species
Different
Does intraspecific competition occur between the same species or different species
Same
What is more intense interspecific competition or intraspecific competition
Intraspecific
Where is the majority of energy lost in transfer from one level to the next on a food chain
as heat, movement or undigested materials
Definition of a pyramid of numbers
Pyramid of numbers show the total number of individual organisms at each level in the food chain of an ecosystem
Definition of a pyramid of energy
A pyramid of energy shows the total quantity of available energy stored in the organisms at each level in the food chain of an ecosystem per year
What are true pyramids of energy
Irregular shapes of pyramids of numbers based on different body sizes
What does the increasing human population require
Increasing food yield
What can this involve
The use of fertilisers or pesticides
What do fertilisers do
provide chemicals such as nitrates, which increase crop yield