Photosynthesis Flashcards
(22 cards)
What is the purpose of a leaf having a waxy cuticle?
Waterproof
Transparent - lets light through for photosynthesis
What are leaf features?
Waxy cuticle
Colour
Veins
Thin
Large surface area
What is the purpose of leaves having a colour?
Pigments absorb wave lengths of light
Why do leaves have veins?
To transport water and nutrients to the cells
Why are leaves thin in structure?
To reduce the leaves mass
Allows light and C02 to get to all cells
Why do leaves have a large surface area?
To absorb the maximum amount of sunlight
What is the purpose of the stoma?
In the vast majority of plants, stomata open during the day, facilitating the capture of atmospheric CO2 —indispensable for photosynthesis — but leaving the door open for water vapour to escape through transpiration
What surrounds the stoma in the leaf?
Guard cells
What is the equation for photosynthesis
Carbon dioxide + water ——> oxygen + glucose
Why are the organs in a plant and what are there purposes?
Stem - transports substances around plant
Leaf - where photosynthesis happens
Root - absorbs water and minerals
Flower - reproductive organ or plant
What is the function of the upper epidermis?
Used for protection
Stops fungi and bacteria getting into the leaf.
What is the function of the Xylem
Transports water and minerals to the leaf.
What is the function of the palisade layer?
Used for photosynthesis
What is the function of the spongy mesophyll?
Used for photosynthesis.
Allows gas exchange in the
leaf.
What is the function of the phloem?
Transports sugar out of the leaf
What is the function of the lower epidermis?
Has stomata to allow carbon dioxide to enter the leaf.
Used for protection
What kind of reaction is photosynthesis?
Endothermic
(An endothermic reaction is one which results in a net decrease in temperature because it absorbs
heat from the surroundings and stores the energy in the bonds formed in the reaction)
Why is light needed?
Light is absorbed by chlorophyll.
The absorbed light is used to break and form bonds between the atoms.
Breaking bonds releases energy
What is the method for the “measuring the rate of photosynthesis in pond weed.” practical?
1.Half fill a boiling tube with sodium hydrogencarbonate solution
2. Cut the stem of the plant at a sharp angle using the scissors. Place plant into the boiling tube with the
cut end at the top.
3.Place the boiling tube into a beaker of water. Add a thermometer and check the temperature during the experiment.
4.Place the lamp 10cm away from the beaker and turn it on
5. Leave the light on the plant for 3 minutes.
6.Count the bubbles released by the plant for 1 minute and record your result in your table.
8. Complete steps 4-5 for 0cm, 20cm, 30cm,40cm and 50cm between the beaker and the lamp
What enters and exits the leaf through the stoma?
CO2 in, O2 and water out
What affects the rate of photosynthesis?
Light
Temperature
Carbon dioxide
