This refers to what happened to the carbohydrate use during photosynthesis this carbohydrate is precisely glucose and can be use in one of the following ways.
- Some glucose can be converted to proteins in the presence of nitrate to be use for growth, repairs and warm-out tissues.
- It can be converted to starch and store during the day to be reconverted back to glucose in the night to be use for respiration.
- Some glucose are also converted to lipids(fat and oil).
- Some glucose are converted to hormones that serves for other purposes.
- Some glucose assist in increase the osmotic pressure of the cell.
Experiment on photosynthesis
- Testing a leaf for starch
Requirement: A destarch plant, water, burnson burner, iodine solution, alcohol.
Procedure
A leaf is first of all a destarched by keeping it in dark room for six hours to prevent the process of photosynthesis. After this the leave is starch free and this process is known as destarching a leaf.
The detached leave is boiled in hot water the boiling stop enzymes action and chemical reaction from taking place. Boiling also help to open the starch green to inhence the penetration of iodine easily. The leave is then remove from the boiled water and put in alcohol and the alcohol decolourises the leave by removing chlorophyll and making the leave to be white.
The leave is then put in alcohol again to make the leave to become hard and brittle at this point the leave become soft and at this point it helps to wash away the alcohol.
EXPERIMENT TO SHOW O2 IS GIVEN OF DURING PHOTOSYNTHESIS
Requirement: Aquatic green plant e.g Eloda canadiensis, test tube, gas funnel, sodium hydrogen carbonate, beaker, support and a glowing splint
Procedure
- A beaker is filled with water and a small amount, half of a tea spoon of sodium hydrogen carbonate is dissolve in water this will supply extra CO2 to the plant.
- An aquatic green plant is placed in a beaker and a funnel by inverted over it.
- A boiling tube is filled with water and the inverted over a funnel stem
- The funnel is raised above the bottom of the beaker with wooden support to allow free circulation of water.
- The experimental setup shown in the diagram is the test experiment
Result: After 30mins gas bubbles from the aquatic green plant start collecting in the inverted test tube.
- The level of water in the test tube drops.
- Sufficient gas has been collected the test tube removed and a glowing splint of wood is inserted into it the glowing splint burses into flame
Conclusion:
Oxygen is produced by an aquatic green plant during photosynthesis.
The decolouries leaf is then spread white surface and iodine solution is the droped on the surface.
If starch is present in the iodine react with starch grains to form a bleu black colour. If starch is not present it is stained with the brown colour of iodine.
Conclusion:
If starch is present in the leaf iodine react with starch grain to far a bleu black colour. If starch is not present it stained with the brown colour of iodine.
AIM: TO FIND OUT IF SUNLIGHT IS NECESSARY FOR PHOTOSYNTHESIS
Requirement: potted plant, iodine solution, opaque or black carbon paper.
Procedure:
Before the experiment was setup the potted plant was placed in darkness for 48 hour to destarch the leave.
- Opaque carbon paper is used to cover a portion of the leaf so that light does not touch this area.
- The carbon paper is held to place by paper clip.
- The setup is exposed to sunlight for atleast six hours
- During the cause of the experiment, the leaf most remaind attarched to the parent plant for it to get a continuous supply of water from the moist soil.
- After six hours the paper clip and then carbon paper are removed from the leaf is then detached from the plant and tested for starch with iodine solution.
Result; The area of the leaf that was covered with the opaque carbon paper will turn brown, indicating a negative test for starch will turn blue black, indicating a positive test for starch.
Conclusion: Sunlight is necessary for photosynthesis.
