Ecosystem Flashcards
habitat definition
the place where an organism lives
population definition
all the organisms of one species living in a habitat
community definition
the population of different species in a specific area at a give time
ecosystem definition
the interaction of a community of living organisms (biotic factors) interacting with non-living (abiotic) part of the environment
Competition of a shared resource can happen between:
- 2 individuals of the same species: intraspecific competition
- 2 individuals of different species: interspecific competition
4 things plants compete for
- light
- space
- mineral ions
- water
4 things animals compete for
- food
- water
- territory
- mates
biotic factor definition
any living factors that affect an ecosystem
name 4 biotic factors
- competition for resources or habitat
- new pathogens
- availability of food
- one species outcompeting another so the numbers are no longer sufficient to breed
abiotic factor defnition
non-living parts of the environment that can affect organisms
name 7 abiotic factors
- light intensity
- Temperature
- Moisture level
- Mineral content and pH of soil
- CO2 concentration
- oxygen levels for aquatic animals
- wind intensity and direction
explain how temperature is a abiotic factor
- animals spend less energy staying warm –> more energy to grow
explain how light intensity is a abiotic factor
- increate rate of photosynthesis enzyme reactions
what is a trophic level
different feeding stages within a food chain
what does Level 1 consist of
Producers: Plant + Algae
- make their own food –> Photosynthesis
- obtain energy from sunlight
what does Level 2 consist of
Herbivores: Primary consumers
- only eat plants/ algae
what does Level 3 consist of
Carnivores: secondary consumers
- eat herbivores
what does Level 4l consist of
Carnivores: Tertiary consumers
- carnivores that have no predators –> they are apex predators
biomass definition
the total mass of dried organic material that makes up a living/ recently decease organism
what does pyramids of biomass represent
they represent the relative amount of biomass in each level of a food chain
what happens to the biomass as your move higher up the trophic levels and why
biomass decreases
- energy is lost between tropic levels
- less organisms are in each higher trophic level
approximately what is the percentage of biomass is transferred to the level above it
10%
Losses of biomass are due to what 3 reasons:
-
excretion - water and
urea
are excreted in urine -
respiration - carbon dioxide and water are waste products of
aerobic respiration
, which is carried out by organisms to keep warm and provide energy for the organism -
egestion - undigested food passes through the organism and is egested as solid
faeces
bioaccumulation definition
build up of toxins / harmful chemicals through consumers
what are the 2 main ways of bioaccumalation
- chemicals enter living organism faster than organism can break it down and use it
- chemicals come into living organism and the organism unable to break it down or excrete it
what are the 4 factors of interdependence
- food security
- pollination / seed dispersal
- shelter + warmth
- decomposition - releases nutrients for future organisms
when do stable communities occur
when all the species and environmental factors are in balance –> so population sizes remain fairly constant
e.g. rainforests, ancient oak woodlands
what are the 4 steps of predator- prey relationships: starting with increase of prey
Step 1: prey population increases –> population size of predator will increase after lag period
Step 2: increase in predators–? decrease in the prey
Step 3: causes decrease* in **no. prey available –> no. predators fall (lack of food)
Step 4: decrease in predators –> no. prey increases , cycle continues
what are the 3 types of adaptation
- structural
- behavioural
- functional
what are structural changes
changes in the organism’s body structure e.g. shape, colour
what are behaivioual changes
changes in how the organism behaves e.g. migration pattern, hibernation, routines, courtship display
what are functional adaptations
internal changes within the organisms body :
- ability to produce very small quantities of urine (desert rate)
- reducing metabolic rate during hibernations
what are organisms called when they live in very extreme conditions
extremophiles
what are some examples of very extreme environments
- high temperature
- high pressure
- high salt concentration
