Photosynthesis Flashcards
Nitrate deficient
Limited growth
Fewer proteins made
Phosphate deficient
Poor root growth
Less minerals are absorbed
Potassium deficient
Yellow leaves and dead spots
Parts of the leaf can’t respire
Magnesium deficient
Leaves turn yellow
Less chlorophyll made
Limiting factor
When it’s in short supply it limits rate of photosynethis
Upper empidermis
Cells are relatively transparent so light can pass through to chloroplasts
Palisade mesophyll
Many chloroplasts
Long and thin so more can fit at top
Spongy mesophyll
Loosely packed cells
Many air spaces provide large SA for gas exchange
Lower epidermis
Small pores called stomata allow CO2 to move in for photo and O2 to leave by diffusion.
Guard cells open in day
Water enters by osmosis
GC swell become turgid so stomata is open for GE in day
Guard cells open in night
Water leaves by osmosis
GC shrivel become flaccid stomata closed preventing water loss at night
Ways plants use glucose produced by photosynthesis
Cellulose
Lipids
Proteins
Sucrose- transportation
Storage- starch
Respiration- energy
Equation for photosynthesis
6CO2 + 6H2O -> C6H12O6 + 6O2
Leaf covered with stencil
In Light turned blue/black
Covered stayed brown
Light allowed photo. Glucose produced + stored as starch
Chlorophyll and no chlorophyll on leaf
C part blue/black
No C part stayed brown
C allows photo. Glucose produced + stored as starch
Limiting rates of photo
Light intensity
Temp
CO2 conc
Effect of light on photo
No light, energy, photo
Increase light, energy, photo
Another factor limiting rate
Effect of temp on photo
Temp + photo increase
OT decrease
Temp increase + KE of enzymes. More collision + photo.
After OT enzymes denature and photo decrease
Effect of CO2 on photosynthesis
As CO2 increases, rate of photo increase until a point where it plateaus.
Hydrogen carbonate indicator
Bright light- photo>resp
Decrease CO2. Purple.
Dark light- resp>photo
Increase CO2. Yellow
No leaf to increase or decrease CO2 concentration. Orange
Steps to test leaf for starch
Pour boiling H2O beaker
Leaf in boilin H2O 1 min
Forceps, remove leaf
Leaf in bottom boil tube
Add ethanol. Decolorize.
Remove. Brittle.
Re-soften H2O. Whitetile
Flood with iodine.
Starch- blue-black
Why place leaf in boiling water for 1 min
Kills leaf. Stops enzyme action. Softens leaf tissue so material enters or leaves
