Photosynthesis

Question 1

photosynthesis

Answer 1

the process by which plants make their own food

Question 2

what is the chloroplasts’ role in photosynthesis

Answer 2

contains a green pigment called chlorophyll which allows for the absorption of sunlight

Question 3

what colours does chlorophyll reflect

Answer 3

green
yellow

Question 4

role of photosynthesis

Answer 4

make food for plant +animal
oxygen produced is used in respiration
removes carbon dioxide from air

Question 5

what is the balanced chemical equation of photosynthesis

Answer 5

6CO2 + 6H2O+ LIGHT ——->C6H 12O6 + 6O2

Question 6

Where specifically is chlorophyll found?

Answer 6

in the thylakoid membrane

Question 7

what are the requirements for photosynthesis to occur

Answer 7

carbon dioxide
water
light energy
chlorophyll

Question 8

source of carbon dioxide

Answer 8

external environment (from the atmosphere)
internally from plant respiration

Question 9

where is carbon dioxide absorbed

Answer 9

through the stomata of the leaf

Question 10

source of water

Answer 10

absorbed from soil through roots by osmosis

Question 11

what is the sun

Answer 11

primary source of energy on earth

Question 12

source of light

Answer 12

sunlight
artificial light in greenhouses

Question 13

end products of photosynthesis

Answer 13

glucose + oxygen

Question 14

give a brief summary of stage 1 of photosynthesis

Answer 14

water is split
light is absorbed
light energises electrons

Question 15

give a brief summary of what happens in stage 2 of photosynthesis

Answer 15

glucose is formed

Question 16

which stage is light dependent and which is not

Answer 16

stage 1= light dependant
stage 2 = not

Question 17

what is water splitting also known as?

Answer 17

photolysis

Question 18

what is the purpose of the light stage

Answer 18

prepares ATP for dark stage

Question 19

where does the light stage occur

Answer 19

thylakoid membrane

Question 20

explain photolysis

Answer 20

some of the trapped light energy is used to split water to oxygen, protons + electrons

Question 21

explain the fate of protons in photolysis

Answer 21

protons:
stored in a proton pool
used to convert NADP+ to NADPH

Question 22

fate of electrons in photolysis

Answer 22

to join with NADP+ to form NADP-

Question 23

fate of oxygen in photolysis

Answer 23

oxygen:
excreted through stomata
used in respiration

Question 24

explain how light is absorbed

Answer 24

each pigment of chlorophyll absorbs a certain wavelength of light.
because chlorophyll has many pigments it means more colours can be absorbed and more light energy is produced

Question 25

why are plants green?

Answer 25

green light is not absorbed and is reflected

Question 26

how is light energy transferred to electrons

Answer 26

all energy absorbed is transferred to the reaction centre chlorophyll located next to an electron acceptor they enter into 1 of 2 pathways this energy energises the electrons, as they jump from one EA to another EA

Question 27

describe cyclic phosphorylation

Answer 27

one electron passes from EA to EA and returns back to the original reaction centre chlorophyll the energy released is used to join ADP+P to form ATP

Question 28

explain non-cyclic phosphorylation

Answer 28

2 electrons pass from EA to EA and do not return to the reaction centre chlorophyll the energy released is used to join ADP+ P to form ATP the low energy electrons join with NADP+ to form NADP- and a proton is added forming NADPH splitting of water occurs to gain more electrons

Question 29

does the dark stage need light?

Answer 29

no

Question 30

where does the dark stage take place

Answer 30

stroma of the chloroplast

Question 31

what is stage 2 controlled by?

Answer 31

controlled by enzymes to speed up the process

Question 32

explain the Calvin cycle (dark stage)

Answer 32

co2 enters Calvin cycle carbon dioxide is reduced to glucose ATP breaks down to ADP+P releasing energy NADPH breaks down into NADP+ +2e + H the electrons and protons are used to make glucose

Question 33

what are the requirements for the light stage to occur

Answer 33

water and sunlight

Question 34

what are the requirements for the dark stage to occur

Answer 34

co2 ATP NADPH

Question 35

end product of the dark stage

Answer 35

glucose