the living world Flashcards
what is an ecosystem
a system in which organisms interact with each other and with their environment
what is an abiotic factor
non living (air water heat rock)
what is a biotic factor
living (plants insects animals)
what is flora
plant life
what is fauna
animal life
what is the nutrient cycle - explain
plants take in nutrients to build into new organic matter. nutrients are taken up when animals eat plants and then returned to the soil when animals die and the body is broken down by decomposers
what is biomass
the total mass of living organisms per unit of area
what is litter
the surface layer of vegetation, which over time breaks down to become humus
what is a biome
a large geographical area of distinctive plant and animal groups which are adapted to that particular environment
what is interdependence
where plants and animals depend on each other for survival, if one component changes there can be serious knock on effects for the entire ecosystem
rainforest biome biodiversity fact
-cover 2 percent of earth surface but home to Half the worlds plants and animals
distribution of tropical rainforests
centred along the equator between the tropics of cancer and Capricorn. found in South America, central Africa and south east Asia. the amazon is the worlds largest rainforest
explain the rainforest nutrient cycle
the hot damp conditions on the forest floor allow for rapid decomposition of dead plant material, this provides plentiful nutrients that are easily absorbed by plant roots. however as these nutrients are high in demand from the many fast growing plants they do not remain in the soil for long and stay close to the surface so if vegetation is removed the soils quickly become infertile
climate of tropical rainforests
-due to presence of clouds, temperatures rarely rise above 32 degrees
-most afternoons have heavy showers
-temperature drops at night because no clouds
layers of the rainforest
emergent
canopy
under canopy
shrub layer
what is a decomposer
an organism such as bacterium or fungus that breaks down dead tissue
what is a food chain
the linear connections between different organisms that rely upon one another as their source of food
what is a food web
a network of many food chains relying on eachother for food
how vegetation has adapted to the rainforest examples
buttress roots - massive ridges to help support the base of the tall trees
drip tip leaves - allow heavy rain to drip off the leaf which prevents algae growing which could block sunlight
name the 5 main biomes
tropical rainforest
tropical grasslands
hot desert
temperate forest
tundra
why are tropical rainforests important
- climate
- water
- resources
- biodiversity
- medicine
- people
- climate change
