ecosystems Flashcards
what is an ecosystem?
made up of all living organisms that interact in a defined area, and the physical factors present. they can vary in size and are dynamic.
what is a biotic factor?
living factors.
e.g. predators, competition, mutualism/parasitism
what is an abiotic factor?
non living factors
e.g. temperature, water, humidity, light, wind, carbon dioxide
why do abiotic factors often have a bigger effect on plants than animals in an ecosystem?
plants are unable to hide / shelter / migrate in extreme conditions
plants are more reliant on light/water in order to photosynthesise
animals can regulate internal body temp
what is a species?
organisms with similar features which reproduce to produce fertile offspring
what is a population?
a group of individuals of the same species that occupy the same habitat at the same time
what is a community?
all populations of different species living in the same place at the same time
what is a biome?
a large scale ecosystem defined by abiotic factors such as weather
what is a biosphere?
an area of the planet where organisms live, including the ground, water and air
why are ecosystems dynamic but stable?
population sizes rise and fall due to interactions between organisms and the environment. any small change can affect the other in predator/prey relationships
what does niche mean?
the role of an organism in its ecosystem e.g where it lives
what does habitat mean?
the place where an organism/community lives
what is a keystone species?
- significant effect on ecosystem
- could be relied on by other organisms
what is a dynamic ecosystem?
constantly changes over time
