lecture 20 - ecosystem energy flow

Question 1

energy ______ through ecosystem while chemicals ______

Answer 1

flow; cycle

Question 2

can energy be lost

Answer 2

yes as heat

Question 3

sun is what type of energy and heat lost to environment is what type of energy

Answer 3

sun = high energy
heat lost to environment = low-form energy

Question 4

photoautotrophs convert

Answer 4

CO2 into organic moleqs

Question 5

how do heterotrophs return CO2 to environment

Answer 5

by performing cellular respiration

Question 6

what does photosynthtesis by plants remove

Answer 6

substantial amounts of atmospheric CO2 each year is about equal to CO2 added to atmosphere through celluluar respiration by producers and consumers

Question 7

carbon can be sequestered in forms that are not readily…

Answer 7

bioavailable

Question 8

burning of fossil fuels and wood is…

Answer 8

non biotic way in which CO2 is contributed to atmospher; volcanos contribute too

Question 9

is nitrogen biologically available

Answer 9

no, but N2 is abundant

Question 10

what forms of nitrogen are biologically useful as nutrients for microbes and plants

Answer 10

ammonium, nitrate, and nitrite

Question 11

waht forms of N can animals take up

Answer 11

organic forms (ie amino acids)

Question 12

nitrogen conversions are mediated by what

Answer 12

microbe metabolism

Question 13

available ______ is often a limiting resource

Answer 13

nitrogen

Question 14

what has increased total nitrogen

Answer 14

industrial production of N fertilzers

Question 15

what are the main limiting micornutrients

Answer 15

-nitrogen (nitrite, nitrate, amminium)
-phosphate
-iron
-calcium
-potassium

Question 16

in terrestt5rial habitats, what is the limiting nutrient usually

Answer 16

available nitrogen

Question 17

what is an daptation legumes have regarding nitrogen

Answer 17

legumes have symbiont nitrogen fixing bacteria in root nodules
-convert atmospheric nitorgen gas into NH3

Question 18

what is typically limiting in freshwater ecosustems

Answer 18

phosphate

Question 19

eutrophication

Answer 19

process by which a body of water becomes enriched in dissolved nutrinets (such as phosphate) that stimulate the growth of aquatic plant life

Question 20

what was banned in all detergents in US in in 1993

Answer 20

phosphate

Question 21

how does energy enter ecosystem

Answer 21

net prunart production (new plant biomass)

Question 22

how does energy flow though ecosystem

Answer 22

trophic interactions (consumption of other organisms)

Question 23

heterotrophs =

Answer 23

quaternary, tertiary, secondary, prumary consymers

Question 24

what do detrivores eat

Answer 24

-quaternary, tertiary, secondary, primary consumers and primary consumers

Question 25

what moves up trophic levels as heterotrophs consume other orgnaisms

Answer 25

matter and energy move

Question 26

food chains

Answer 26

show how food energy is transferred from trophic level to trophic level, beginning with producers

Question 27

decomposers =

Answer 27

detritivores

Question 28

decomposers eat

Answer 28

deritus

Question 29

deritus

Answer 29

decaying materal, waste products and dead organisms

Question 30

food webs

Answer 30

show more complex interactions among orgnisms than food chain

Question 31

can a species play more than one role at more than one trophic level

Answer 31

yes

Question 32

how can food webs be simplified

Answer 32

by grouping species with similar trophic relationships into broad functional groups