Photosynthesis Flashcards
What is photosynthesis
Process in which plants trap light energy using their chloroplasts to produce energy/food
What is the word equation for photosynthesis
Carbon dioxide + water -> glucose + oxygen
Balanced symbol equation for photosynthesis
6CO2 + 6H20 -> C6H12O6 + 6O2
Photosynthesis is a endothermic reaction, what is a endothermic reaction
Reaction what requires energy to be absorbed to work
When glucose is produced in photosynthesis it is usually converted into what for storage
Starch
One way to show that photosynthesis is proving that starch is present in a leaf, what is the method for this experiment for the starch test
- put leaf in boiling water, to kill the leaf and stop further reactions
- put leaf in a boiling tube with ethanol, place tube in boiling water bath, ethanol will soon start to boil at 78 degrees, thus quick remove the chlorophyll from the leaf
-Dip leaf in boiling water again it make the leaf soft and less brittle
- spread the leaf on a white tile and add iodine, of the starch is present the iodine will turn from yellow-brown to blue-black
Before carrying out experiments into photosynthesis what is it necessary to do
Destarch the plant, this involves leaving it in darkness for 48 hrs.
(To ensure reaction on what you are finding only occurs in the investigation)
Steps to show light is needed for photosynthesis
- destarch plant
- partially cover leaf with foil
- leave in bright light for at least 6 hrs
- test the leaf for starch (method stated in other flash card )
Steps to show chlorophyll is needed for photosynthesis
- destarch variegated leaf
- put it in bright light for at least 6 hrs
- test for starch (method in other flash card)
Steps to show carbon dioxide is needed for photosynthesis
- destarch plant
- set up a plant covered with a clear plastic bag, seal it with an elastic band ans place sodium hydroxide solution inside the bag with the plant, to absorb ant carbon dioxide inside the bag.
-leave the plant in bright light for at least 6 hrs
- test one of the leaves for starch (method in other flash card)
How to show oxygen us produced in photo synthesis
-Set up a beaker with water and a water plant inside,
-turn a funnel upside down and place it on top of the plant
- place test tube on top of upside down funnel to collect oxygen bubbles
- place in bright light for at least 6 hrs
We can then show oxygen bubbles are produced and place a glowing splint in the test tube and it will relight.
We can also use this same setup to measure different rates of photosynthesis with different light intensities by moving a lamp. The rate of bubbles produced will show the change
Limiting factors of photosynthesis
Light
Carbon dioxide
Temperature
Hydrogen- carbonate *(bicarbonate) indicator is red what colour does it turn with increased and decreased carbon dioxide levels
MY LIPS (more yellow) (less is purple)
Does the epidermis have chloroplasts
No
Does the palisade mesophyll layer have chloroplasts
Yes many
What does the spongy mesophyll layer have
Intercellular airspace’s and fewer chloroplasts
3 adaptations a leaf has for light absorption
- large SA
- thin, transparent cuticle
- presences of many tightly packed palisade mesophyll cells, end on to the upper surface with many chloroplasts rich in chlorophyll
3 adaptations a leaf has for gas exchange -
- spongy mesophyll cells have a large SA for gas exchange
- intercellular air spaces in “” allow CO2 to enter and oxygen to leave the photosynthesising cells which are mainly concentrated in the palisade layer
- stomata allow co2 and o2 to enter the leaf; guard cells can open and close the stomata pore (in many the guard cells are open during the day and close at night)
What is the waxy cuticle for
Prevents evaporation and acts as a physical defence against microorganism infection
