Photosynthesis

Question 1

RUBSICO

Answer 1

sometimes reacts with oxygen instead of co2 so carbon isnt fixed

Question 2

hot days

Answer 2

stomata close to stop water loss, but this increases oxygen so photorespiration occurs (when o2 levels high), photorespiration occurs instead of photosynthesis,

Question 3

photorespiration

Answer 3

when oxygen levels are high, useless as doesnt make sugar

Question 4

c3 plants

Answer 4

3 carbon molecule, standard photosynthesis, high photorespiration, not a lot of energy needed, most plants do this

Question 5

c4 plants

Answer 5

adapted to HOT conditions, has carbon 4 molecule fixed by pep, that moves to bundle sheath cells and goes to calvin cycle . not many do this, grasses, FIXED SPATIALLY, STILL HIGH O2 BUT NOT PHOTORESPIRATION AS CARBON GOES TO BUNDLE SHEATH AND CANT REACT WITH RUBISCO

Question 6

CAM plants

Answer 6

carbon 4 molecule fixed by pep AT NIGHT which stored as malic acid in vacuole, stomata open at night to lose less water, succulents, FIXED TEMPORARILY

Question 7

c4 evolution

Answer 7

evolved 63 times, due to reduction of co2, higher co2 favours c3, higher temp favours c4

Question 8

rice

Answer 8

c3 plant but people are wanting to change to c4 to use hot conditions

Question 9

CAM evolution

Answer 9

evolved 35 times due to hot conditions and less co2

Question 10

importance of photosynthesis

Answer 10

primary productivity, energy transfer

Question 11

gross primary productivity

Answer 11

total amount of carbon captured

Question 12

net primary production

Answer 12

stored biomass

Question 13

controls of top down trophic levels

Answer 13

predation

Question 14

controls of bottom up trophic levels

Answer 14

light, nutrients

Question 15

humans and trophic levels

Answer 15

cause trophic downgrading due to killing predators