Unit 3 Chapter 5 - Photosynthesis Flashcards
What is photosynthesis?
the process in which light energy is converted to chemical energy stored in sugars (glucose)
What is the equation for photosynthesis?
12H2O + 6CO2 -> 6O2 + C6H12O6 + 6H20
What is a biochemical pathway?
a series of enzyme-catalysed biochemical reactions in which the product of one reaction becomes the substrate in the next reaction.
Where does photosynthesis happen?
chloroplasts
Where is the chlorophyll in photosynthetic prokaryotic cells?
suspended in the cell cytoplasm
What is the chloroplasts folded inner membrane called?
thylokaid membranes
What are the little stacks in chloroplasts called and what are they made of?
thylakoids made up of grana (one granum)
What is chlorophyll?
green light absorbing pigment, found in the grana of the chloroplast
What is the stroma?
gel-like fluid enclases by the inner membrane, which is rich in enzymes
What is the palisade mesophyll’s role in photosynthesis?
where chloroplasts are concentrated near the top of the leaf (recieve most sunlight)
What is the spongy mesophyll’s role in photosynthesis?
where gases can build up as they enter and leave the leaf
What is the cuticles’s role in photosynthesis?
prevents water loss
What is the xylem’s role in photosynthesis?
- transports water into leaf
- veins are surrounded by cells called bundle sheath cells
What is the stomata’s role in photosynthesis?
- small openings which control gas exchange
- if water loss is excessive, plants close their stomata during day which decreases rate of photosynthesis?
What are the 2 stages of photosynthesis?
light dependent stage
light independent stage
Where does the light dependent stage occur?
grana or thylakoids
What are the inputs for the light dependent stage?
- light
- water
- NADP+
- ADP + Pi
What are the outputs for the light dependent stage?
- oxygen
- NADPH
- ATP
Where does the light independent stage occur?
stroma of chloroplasts
What does the light independent stage involve?
- conversion of CO2 into glucose
What are the inputs for the light independent stage?
- carbon dioxide
- ATP
- NADPH
What are the outputs for the light independent stage?
- water
- glucose
- ADP + Pi
- NADP+
What is the role of NADPH in photosynthesis?
transfers hydrogen (H+) from the light dependent to light independent stage to form glucose
What is the role of ATP in photosynthesis?
transfers energy from the light dependent to the light independent stage
What is the role of rubisco?
- responsible for catalysing the first stage of the light independent stage (CARBON FIXATION)
What is the problem with rubisco?
- active site that both carbon dioxide and oxygen can bind to
What happens if carbon dioxide binds to rubisco?
- CO2 is converted into RuBP
What happens if oxygen binds to rubisco?
- prevents CO2 from binding, thus preventing it from entering the calvin cycle
- protorespiration occurs
