topic 1 and topic 2 Flashcards
define ecology
the study of the interactions between organisms and the environment in which they live.
define ecosystems
community of interdependent organisms and the physical enviornment they interact with.
biotic components
Producers→ the plants that convert energy into matter
Consumers→ animals that eat plants or other animals
Decomposers→ organisms that breakdown waste into component parts for reuse
Temperature
Sunlight
pH
Salinity
Precipitation
abiotic components
habitat
A habitat is the environment in which a species usually lives.
define niche
The niche is the role an organism plays and the position it holds in the environment. It includes all the interactions the organism has with the abiotic and biotic environment.
density-dependent factors
factors that affect the population only when it reaches a certain density. These include competition, disease, parasitism and predation (biotic factors most often)
Density independent factors
factors that control population no matter what the density of it is. They include sunlight, temp, water, and natural disasters.
Carrying capacity:
maximum number of individuals of a species that the enviornment can sustainably support in a given area.
J-shaped population curve:
shows exponential population growth under ideal conditions with plenty of resources and limited competition.
S-shaped population curve:
S-shaped curve is more likely when resources are limited-they are limited factors. Exponential growth is only possible for a short period of time. Population grows, resources are depleted and growth rate slows and eventually plateau’s.
→ likely to be accurate until the population approaches the carrying capacity.
species
group of organisms with common characteristics that can interbreed to produce fertile offspring.
Population
A population is a group of individuals of the same species living in the same area at the same time.
population size is determined by:
Population size is determined by births and immigration (which increase the population) and by deaths and emigration (which decrease the population).”
define community
A group of populations living and interacting with each other in a common habitat
producers
Producers convert inorganic compounds into food.
Autototrophs (self-feeders)- they obtain food by making it for themselves.
Primary producers
Plants
Manily photosynthesis, small amount by chemosynthesis/
Consumers
Reffered to as heterotrophs (other-feeders)
Herbivores eat just plans-leaves, flowers, fruits and nuts or stems, adn wood.
Omnivores eat both plants and other animals.
Carnivores eat only meat/other animals and these are the predators.
Decomposers and detritivores:
“clean up crew” for ecosystems.
→ Obtain their energy and nutrients from dead plant and animal material and waste.
→ detritivores are the first stage of the decomposition cycle. E.g (millipedes, woodlice, worms and maggots)
Decomposers: decomposers such as bacteria and fungi absorb and metabolise waste and dead matter on a molecular level then release it as inorganic chemicals that can be recycled through the ecosystem via plan
Photosynthesis
Carbon dioxide + water–> light chlorophyll–> glucose + oxygen
Respiration
Glucose + oxygen–> Oxidation–> carbon dioxide + water + Energy
bioaccumulation
the increase in the concentration of a pollutant in an organism as it absorbs or it ingests it from its environment
Biomagnification:
the increase in the concentration of the pollutant as it moves up through the food chain,
Biomass:
The mass of living organism in a given area expressed as dry weight of mass per unit of area of g m–2
Productivity:
The conversion of energy into biomass in a given time expressed as. The rate of growth of plants and animals in the ecosystem. In business it is how much output you get from your input, usually measured annually.
