Photosynthesis Flashcards
Where does the Light Dependent reaction take place?
Grana
What is a redox reaction?
One that involves oxidation and reduction
What is a coenzyme?
A molecule which aids the function of an enzyme
What is NADP?
A coenzyme used in photosynthesis to transfer hydrogen
Is there an ETC in photosynthesis?
Yes
What happens when light energy is absorbed by chlorophyll in PSII?
Electrons are excited, and they move to a higher energy level, to the ETC and to PSI.
Light splits water and ATP is made
In photosynthesis the use of light in making ATP from ADP +Pi is called…?
Photophosphorylation
What do we get at the end of the Light Dependent reaction?
ATP
Reduced NADP
Splitting of water into hydrogen ions, electrons and oxygen
In Calvin’s experiment to investigate the Light independent reaction, what was the purpose of the hot methanol?
To kill the algae, stopping any further reactions taking place
Why did Calvin use the radioactive isotope of carbon in his CO2?
So he could see what happened to the carbon dioxide.
What are the main limiting factors for photosynthesis?
Carbon dioxide concentration
Temperature
Light intensity
Which molecule is made in the Calvin cycle and used to make organic substances?
Triose phosphate or TP
Which substance does ribulose biphosphate (RuBP) join with to make 2 x GP?
CO2
Which enzyme catalyses the reaction between CO2 and RuBP in the Calvin cycle?
Rubisco or ribulose biphosphate carboxylase
What is needed to make the 2 x TP from 2 x GP
ATP and NADPH from the Light Dependent reaction
5 out of every 6 molecules of TP are not used to make organic compounds. What are they used for?
To regenerate RuBP using ATP.
How many times does the Calvin cycle need to turn to get a hexose (6C) sugar?
6 times
What are lipids formed from?
Glycerol made from TP and fatty acids from GP
Chlorophyll a, chlorophyll b and carotene absorb 2 main colours of sunlight. Which are they?
Red and blue
Why do a lot of plants look green?
Because green light is reflected
What is the optimum temperature for photosynthesis?
25 degrees Celsius
What is the optimum carbon dioxide concentration for photosynthesis?
0.4%
