topic 6.3.1: ecosystems

Question 1

how is energy lost between trophic levels

Answer 1

respiration and excretion

Question 2

what is the equation for biomass efficiency

Answer 2

biomass transferred/ biomass intake x100

Question 3

how is biomass measured

Answer 3

dry mass/ given area

Question 4

how can humans manipulate transfer of biomass

Answer 4

-restricting movement
-higher energy food
-keeping warm
-removing competition/predators

Question 5

N2

Answer 5

atmospheric nitrogen

Question 6

NO2-

Answer 6

nitrite ions

Question 7

NO3-

Answer 7

nitrate ions

Question 8

NH2

Answer 8

amine group

Question 9

NH3

Answer 9

ammonia gas

Question 10

NH4+

Answer 10

ammonium ions

Question 11

what are the 5 stages of the nitrogen cycle

Answer 11

fixation, nitrification, assimilation, ammonification, denitrification

Question 12

fixation

Answer 12

N2 -> NH3
symbiotic relationship
anaerobic

Question 13

rhizobium

Answer 13

fixes nitrogen inside root nodules

Question 14

azotobacta

Answer 14

fixes nitrogen in soil

Question 15

nitrification

Answer 15

NH3 -> NO2- -> NO3-
oxidation

Question 16

nitrosomonas

Answer 16

ammonia to nitrites

Question 17

nitrobacters

Answer 17

nitrite to nitrate

Question 18

assimilation

Answer 18

NO3- -> NH2

Question 19

ammonification

Answer 19

NH2 -> NH3
saphrobionts and detritivores

Question 20

denitrification

Answer 20

NO3 -> N2
reduction, anaerobic
soil

Question 21

carbon cycle- photosynthesis

Answer 21

fixed during calvin cycle (rubisco carboxylates rubp)

Question 22

carbon cycle- sedimentation

Answer 22

dead plants form layers of sediment, storing carbon

Question 23

carbon cycle- respiration

Answer 23

released from link and krebs, and fermentation

Question 24

carbon cycle- decomposition

Answer 24

detritivores feed on dead matter
saprophytes decay dead matter
carbon released

Question 25

what is succession

Answer 25

change in ecological community over time

Question 26

3 stages of primary succession

Answer 26

pioneer comm, intermediate comm, climax comm

Question 27

pioneer community

Answer 27

colonies bare rock or sand, adapted for harsh abiotic factors, forms humus, low range and short life cycle

Question 28

intermediate community

Answer 28

mosses and smaller plants survive, increased nutrient content of soil

Question 29

climax community

Answer 29

trees, larger range, longer life cycle, outcompetes previous species, most stable

Question 30

deflected succession

Answer 30

human activity prevents climax community