Basics of a System, Ecology and Energy Flow Flashcards
a network of interdependent components and processes (materials and energy)
system
part of a system that stores resources (compartments or stocks)
state variables
how resources move from one compartment to another
flows
flow of resources into, through, and out of a system
throughput
system- receive inputs from surroundings; produce outputs that leave the system
open system
system- no exchange of matter or energy with surroundings
closed system
stable balance in a system over time
equilibrium
sudden or rapid change that happens past certain limits in a system
tipping points
feedback loop- diminishes a process or component
negative feedback
feedback loop- increases a process or a component
positive feedback
when specific numbers of resources or energy vary but the overall trend is stable (variation around a stable average)
dynamic equilibrium
events or activities that interrupt normal feedback loops
disturbances
when components of varying properties come together to form a system, a new property emerges which was not present in the previous components
emergent properties
interactions of organisms with each other
biotic
interactions of organisms with their physical environment
abiotic
law- energy can neither be created nor destroyed. energy is conserved
1st law of thermodynamics
law- with each energy transfer (or transformation) in a system, less energy is available to do work
2nd law of thermodynamics
(or disorder) tends to increase in natural systems
entropy
series of light-dependent reactions. produces oxygen gas and glucose
light –> chemical
energy captured
photosynthesis
process of releasing chemical energy. involves splitting C and H atoms from glucose
chemical –> heat
energy released
cell respiration
an open system with dynamic equilibrium
constant input and output of energy
composed of biological community+physical environment
ecosystem
organisms that produce organic material through photosynthesis
producers
amount of biomass produced in a given area during a given period of time
productivity
an organism’s feeding status in an ecosystem
trophic level
autotrophs- feed themselves usually through photosynthesis
producers
heterotrophs- eat other animals or plants for energy and nutrients
consumers
organisms that clean up dead carcasses
scavengers
organisms that consume litter, debris, and dung
detritivores
organisms that breakdown and recycle
decomposers
what is the 10% rule
only 10% of the energy in one trophic level is passed on to the next
