1. Moisture and rainfall
a limiting factor that affects the rate of photosynthesis is moisture and rainfall. water is a compound containing two hydrogens atoms and one oxygen. Water can be found as a solid, liquid and gas. Plants need water to be as a fluid which Can flow freely without a fixed shape. Water freezes at 0⁰C AND BOILS AT 100⁰c. liquid water is made available to plants as surface water, soil moisture, or groundwater.

2. How plants gain water
PHOTOSYNTHESIS IS WHEN GREEN PLANTS, WITHIN THE CHLOROPHYLL USE SUNLIGHT TO SYNTHESIZE NUTRIENTS AND GLUCOSE FROM CARBON DIOXIDE AND WATER AND GENERATES OXYGEN AS A PRODUCT. PLANTS NEEDS WATER FOR PHOTOSYNTHESIS.
PLANTS ABSORB WATER FROM THE SOIL. WITHIN THE SOIL ROOTS MEET AIR, WATER AND NUTRIENT RESERVES. WHEN THE WATER GETS IN THE SOIL, THE ROOTS WILL ABSORB THE NUTRIENTS AND THIS WILL HELP THE PLANT TO GROW. THE ROOTS HAVE A CELL CALLED ROOT HAIR CELL - THESE GET THE WATER AND MINERAL IONS BY ABSORBING FROM THE SOIL INTO THE ROOTS. ROOTS HAVE A BIG SURFACE AREA AND THIN WALLS, WHICH ALLOW WATER TO PASS THROUGH THEM EASILY.

3. investigation
We will have 5 tomato plants, going from completely dry soil to completely waterlogged with 30cm high plants. We would have 1 plant which doesn’t get watered at all then it goes from 10cm3, 25cm3, 100cm3 and 200cm3 getting watered twice a day. We would also make sure there are no holes in the plant pot so the water is fully retained in the pot so the plant can absorb it all. We would measure growth over 3 months measuring