Revision🤩😅 Flashcards
Carbon dioxide
Comes from the air, diffuses into the leaf via stomata (tiny holes)
Water
Absorbs into the roots
Glucose
Made in the leaves during photosynthesis
Oxygen
Diffuses out into the air through stomata
Waxy cuticle
Protests and stops water loss
Palisade layer
The sunlight hits the top
What do plants do with Glucose?
They use it grow
Cytoplasm
Where chemical reactions occur
Nucelus
Contains DNA that stores information to control the cell
Cell wall
Contains cellulose to give the cell strength and support
Vacuole
Contains cell sap to provide support for the cell
Cell membrane
Controls what goes in and out of the cell
Chloroplasts
Contains chlorophyll to trap light and be the site of photosynthesis
What is photosynthesis
Photosynthesis uses light energy to make glucose that contains energy. Without this the plant can’t grow
Using glucose (what 5 things)
Respiration
Lipids
Cellulose
Protein
Starch
How to show a leaf is photosynthesising
1)Boil leaf in water to soften and kill cells
2)Boil leaf in ethanol to break down chlorophyll
3)Rinse leaf in water to remove ethanol
4)Test with iodine (any part that goes blue/black obtains starch)
How to measure the RATE of photosynthesis
Put the pond weed in sodium hydroxide solution and put the tube in a bowl of water and bring it nearer to the light by 10cm each time and record the amount of bubbles per minute at 10-50 cm
So what did we learn from the rate of photosynthesis?
The closer the light the more oxygen meaning more photosynthesis but it will slow down if the plant gets TOO MUCH light until it eventually stops
How do you test for presence of oxygen
Glowing splints relights
State the 3 factors that affect the rate of photosynthesis
Light intensity
Carbon dioxide concentration
Temperature
Nitrate
Role For healthy growth, to make proteins
Symptoms:
Poor growth
Older leaves are yellow
Phosphorus
Role:
For healthy roots
Symptoms:
Poor root growth
Younger leaves are purple
Potassium
Role:
For healthy, leaves and flowers
Symptoms:
Yellow leaves with dead patches
Magnesium
Role:
For making chlorophyll
Symptom:
Plants turn yellow
What is fertilisers
Chemicals applied to soil to replace minerals taken out of soil
Why do farmers use fertilisers?
As crops are harvested, they do not die and replace minerals take from soil, so fertilisers are used to prevent future crops suffering from mineral deficiency.
