on the wild side

Question 1

what is the role of photosynthesis in the carbon cycle?

Answer 1

carbon dioxide is reduced to form organic molecules

Question 2

what is meant by the term ecosystem?

Answer 2

organisms and abiotic factos

Question 3

explain why the value for GPP is lower than the light energy available to the ecosystem

Answer 3

not all light falls on the leaves
some light reflected
some light misses chloroplasts
some light is the wrong wavelength

Question 4

explain why respiration affects the production of biomass

Answer 4

GPP - R = NPP
organic molecules used in respiration to provide energy
because the more organic molecules used in respiration, the less is available for the production of biomass

Question 5

describe how starch is formed from the products of light independent reactions

Answer 5

2 GALP used to produce a glucose molecule
joined together by glycosidic bonds to form starch
by condensation reactions
producing amylose and amylopectin

Question 6

describe the light dependant reactions of photosynthesis

Answer 6

light energy excited electrons in chlorophyll
photolysis of water to produce O2, e-, H+
e- used in e- transport chain
generation of ATP
reduction of NADP

Question 7

why does increasing CO2 conc affect the growth of plants in greenhouses?

Answer 7

co2 is a limiting factor
co2 fixed to produce GP
increased co2 results in more glucose produced
which would lead to a greater rate of growth

Question 8

describe the roles of the products of light dependant reactions in the Calvin cycle

Answer 8

ATP and NADPH
ATP used by the enzyme converting GALP to RuBP
NAPH used to convert GP to GALP

Question 9

explain the importance of rubisco to the productivity of an ecosystem

Answer 9

fixes inorganic carbon
allowing formation of organic molecules
organic molecules allow transfer of energy to next trophic level

Question 10

explain the relationship between the structure and functions of a granum in photosynthesis

Answer 10

formed of layers of thylakoid membranes to increase sa

thylakoid membranes contain chlorophyll to absorb light

electron carrier molecules in thylakoid membrane involved in ATP production

Question 11

describe the difference between the terms niche and habitat

Answer 11

niche is the way an organism interacts with its environment
habitat is the place where an organism lives

Question 12

explain how CO2 is removed from the air into the oceans

Answer 12

CO2 dissolves in the oceans

for carbon fixation/ light independent reaction

by photosynthesis of seaweed/ algae/ plankton/ autotrophs

Question 13

name of the reaction when ADP is converted to ATP

Answer 13

phosphorylation

Question 14

name of the reaction when ATP is converted to ADP

Answer 14

hydrolysis

Question 15

which molecule is found in the photosystems

Answer 15

chlorophyll

Question 16

in which part of the chloroplast does the reduction of NADP take place

Answer 16

stroma

Question 17

describe the role of the electron transport chain

Answer 17

movement of H+ ions across thylakoid membrane

ATP production

Question 18

describe the role of rubisco in the production of Galp in the light independent reaction

Answer 18

rubisco is an enzyme

in the Calvin cycle

involved in carbon fixation/ bonding of CO2 to RuBP/ reaction between CO2 and RuBP

to form GP

GP converted to GALP

using ATP and NADPH

Question 19

describe how the membranes inside the chloroplast are involved in photosynthesis

Answer 19

site of light dependant reaction

chlorophyll/ photosystems/ electron carrier proteins on membrane

ATPsynthase in thylakoid membranes

thylakoid membranes provide a place for accumulation of H+

phosphorylation

Question 20

state what is meant by the term Q10 temperature coefficient

Answer 20

the ratio of the rate of an enzyme reaction taking place at temperatures differing by 10º

Question 21

what are the units of NPP

Answer 21

kJ m-2 year-1

Question 22

explain the meaning of the term GPP

Answer 22

rate of energy incorporated into biomass in producers/ plants

Question 23

explain why NPP is lower than GPP

Answer 23

NPP = GPP - R
energy lost as heat

Question 24

explain why burning wood chips does not increase carbon dioxide to the atmosphere in the long term

Answer 24

CO2 produced by burning wood replaces that absorbed by trees

trees fix carbon/absorb CO2 from atmosphere for photosynthesis

new trees grown to replace those that are cut down/ carbon neutral

therefore no net increase in CO2

Question 25

explain how reforestation can be used to minimise climate change

Answer 25

new/ young/ growing trees

more CO2 taken in by photosynthesis than released by respiration/ trees act as a carbon sink

therefore reducing CO2 in atmosphere

which slows the rate of global warming/ reduces greenhouse effect

Question 26

describe how forests can be managed as a sustainable resource

Answer 26

replacing trees that have been cut down

cut down older trees

replace w seedlings/ young/ rapidly growing trees