Photosynthesis

Question 1

What are the two stages of photosynthesis?

Answer 1

Light dependent reaction, light indapendent reaction

Question 2

How many atps does photosynthesis make?

Answer 2

2

Question 3

What does the light dependent reaction produce?

Answer 3

Atpand nadph, nadph2 or rediveed nadp

Question 4

Where does light dependent reaction take place?

Answer 4

Thylakoids and grana

Question 5

What does the light independant reaction require ?

Answer 5

Products of ldr

Question 6

What is the role of light independent reaction?

Answer 6

Reduces c02- c6h1206 (glucose)

Question 7

What is a co enzyme?

Answer 7

Molecules that like to carry H to electron transport chain. They donate their H atom to the etc. Energy from the electron is used to generate atp.

Question 8

What are the stages of the ldr?

Answer 8

Chlorophyll absorbs energy , 2 electrons are emitted from photoionisation. 2e- pass down an etc into the thylakoid membrane, energy is released and used to phosphorylate ADP. Light strikes h2o and splits into 2e- and 2h ( which are returned to chlorophyll) +1/2 C. Energy released during photolysis is used to pump h+ ions into the thylakoid space creating a proton gradient across thylakoids membrane. H+ ions move back across membrane via atp synthase enzyme which releases energy. Low energy e- +H+ combine to form H. This reduces the Co enzyme nadp

Question 9

What is an electron transport chain?

Answer 9

Electron carriers that form a chain in the inner mitochondrial membrane, each electron carrier in the chain is at a lower energy level. co enzyme donates electrons to these carriers energy is released as electron moves down the etc

Question 10

What products does lir need from ldr?

Answer 10

Atp nadph

Question 11

Where does the light indapendent reaction occur?

Answer 11

In the stroma of the chloroplasts.

Question 12

What are the limiting factors of photosynthesis?

Answer 12

Light intensity, light quantity, temperature,concentration of co2, chlorophyll concentration

Question 13

What happens when something is reduced?

Answer 13

It is the gain of electrons

Question 14

What happens when something is oxidised?

Answer 14

Oxidation is the loss of electrons

Question 15

What are examples od co enzymes?

Answer 15

NAD, FAD, NADP

Question 16

How many carbon molecules are used in the lir to regenerate RuBp?

Answer 16

5/6

Question 17

What is RUBISCO?

Answer 17

It is the enzyme that catalyses the reaction between RuBp+ Co2

Question 18

What are the steps of the lir/calvin cycle?

Answer 18

Co2 combines with acceptor molecule rubp. Rubisco catalyses this reaction producing an unstable 6c molecule which splits to form 2xgp. Gp is reduced to TP. hydrolysis of atp provides energy for this reaction. NADH forces electrons into gp reducing it. Tp is formed and converted to useful organic substances eg fructose/glucose. 5/6 carbons of tp is used to regenerate the acceptor molecule rubp. This ensures continued fixator of co2 and production of gp is remain

Question 19

How do you measure CO2?

Answer 19

Measure vol of co2 absorbed in a given time

Question 20

What is the NET rate of photosynthesis?

Answer 20

Volume of CO2 absorbed from the the atmosphere in a time period.

Question 21

What is the GROSS rate of photosynthesis?

Answer 21

Atmospheric co2 used in photosynthesis plus, co2 produced in respiration that is used in photosynthesis

Question 22

What do farmers do in summer to overcome limiting factors?

Answer 22

Ventilate greenhouse- to remove excess heat and replenish co2

Question 23

What do farmers to overcome limiting factors in winter?

Answer 23

Enrich co2 concentration via combustion of co2 pellets, heat green houseses which removes temperature as a limiting factor, install lighting pannels illuminate crops for longer duration