Energy Flow Flashcards
(14 cards)
1
Q
what is bioenergetics?
A
- the concept of energy flow through the biosphere
- begins with the sun as a source of energy, the to plants, then to either consumers (animals) or to decomposers (fungi, bacteria), then heat is released
2
Q
what is photosynthesis?
A
plants use solar energy to turn CO2 into chemical energy (ATP and NADPH) which is used to create carbohydrates
- 6CO2 + 6H2O -> C6H12O6 + 6 O2
3
Q
what is a food chain?
A
- linear sequence of organisms in which nutrients and energy are passed
- each organisms takes up a trophic level
- primary producers (photosynthetic organisms) - primary consumers (herbivores) - secondary consumers (omni/carnivores) - tertiary consumers - apex predators
4
Q
how is energy lost in the food chain
A
- energy is lost as heat between each trophic level
- remaining energy may not be sufficient to support higher trophic levels (usually maxes out at 4-6 levels)
- 2nd law of thermodynamics
5
Q
What are food webs?
A
- account for complex consumer relations
- Grazing web: plants at base-herbivores-carnivores
- Detrital web: fungi and bacteria that feed on dead organisms
6
Q
how is energy obtained by living organisms?
A
- autotrophic: synthesize energy either by photosynthesis or chemosynthesis
- heterotrophic: consume and digest organisms for energy
7
Q
what is productivity in an ecosystem
A
- % of energy entering the ecosystem and becoming incorporated into the biomass
- measured in kcal/m^2/yr
- gross primary productivity is the rate at which primary producers take up solar energy
8
Q
what is biomass?
A
- total mass at a specific time of organisms currently living at a trophic level
9
Q
what is trophic level transfer efficiency?
A
- measurement of efficiency of energy between trophic levels
- (production at present trophic level)/(production at previous trophic level) x 100
10
Q
what is net production efficiency?
A
- quantification of how organisms efficiently incorporate the energy they receive into biomass
- (net consumer productivity)/assimilation x 100
11
Q
What are ecological pyramids?
A
- Charles Elton, shows trophic levels and related parameters
- numbers, biomass, energy
12
Q
What is the pyramid of numbers?
A
- based on the numbers of individuals at different trophic levels
- upright or inverted
13
Q
What is the pyramid of biomass?
A
- measures quantities of E converted into living tissue at different trophic levels
- upright
14
Q
What is the pyramid of energy?
A
- E flow through different trophic levels - upright
