The Latin word Respirae means to breathe. The biochemical process in which complex organic compounds in living cells are oxidized to simple compounds and static energy is converted into kinetic energy is called respiration. Respiration is a powerful oxidative process that transfers energy. ATP is produced in the organism as a result of respiration. This ATP provides energy for all physiological functions of the organism. Growth occurs in the cytoplasm and mitochondria of cells. It takes place 24 hours a day and night.
C6H12O6 +6O2+6H2O→ 6CO2+12H2O+36ATP(CH3-CO-COOH)

Theory : The word Photosynthesis is composed of the English word Photo meaning light and synthesis meaning synthesis. Photosynthesis means the combination of several substances to create a compound. The biochemical process in which green plants combine water and carbon dioxide with the help of chlorophyll in the presence of sunlight to produce sugary food and release oxygen as a by-product is called photosynthesis. Charles Barnes first used the term Photosynthesis in 1898.

Necessary Materials
1. A deciduous tree with long leaves.
2. Large mouth glass bottle- 1.
3. 20% caustic potash solution.
4. Petridis with water – 1.
5 Chopped oysters – 1.
6. Vaseline or wax.
7. 80% alcohol.
8. 1% iodine solution.

Procedure or course of action
1. Before the test, the plant with the tub was kept in a dark room for three days and sterilized.
2. Tilting the large-mouthed bottle on the table, I took some caustic potash solution inside the bottle.
3. I took a long leaf with pods from a tree kept in the dark. I inserted the tip of the sheet into the bottle through the cut hole.
4. I dipped the leaves in watery Petridis.
5. For airtightness, I coated the cut part with vaseline or beeswax to seal the gap well.
6. I left the test with the leaves in the sunlight.
7. After 3-4 hours the leaf was taken out of the bottle and boiled in 80% alcohol. The leaves became discolored due to chlorophyll loss.
8. The discolored leaf was thoroughly washed in water and soaked in 1% iodine solution for 1 minute.
9. The leaf was removed from the iodine solution, washed in distilled water and placed on a clean white paper.
observation
It was observed that the part of the leaf which was outside the bottle turned blue or black on contact with the iodine solution. But the leaf inside the bottle did not change color.

Decision
The part of the leaf inside the bottle received sunlight, water and oxygen, but no CO2. So no sugar or sugar is produced. CO2 is essential for photosynthesis.

warning
1. I kept the plant in the dark for a certain time.
2. I closed the mouth of the bottle well with vaseline so that there is no gap.
3. I boiled the leaf well.
4. I took care not to use chemicals in the body.
5. I observed well.

1. In photorespiration, RuBP carboxylase acts as RuBP oxygenase in higher concentrations of oxygen.
2. Food produced in the process of photosynthesis is oxidized in light respiration. So it is a harmful method.
3. ATP is not produced in photosynthesis. So it cannot be called real breathing.
4. Photorespiration consumes ATP and NADPH+H+.
5. This process protects the plant from stress.
6. This process is indirectly beneficial for photosynthesis.
7. Glycine and serine are produced in this process.

Photorespiration takes place in the chloroplasts, peroxisomes and mitochondria of plants.

Carbon compounds are broken down in photosynthesis to release CO2. No ATP is produced in this process. So light respiration is not called true respiration.

The process by which green plants take in oxygen and release CO2 in the presence of light and produce phosphoglycolate is called photorespiration. Photorespiration occurs when intense light and high temperatures occur during the Calvin cycle. In intense light and high temperature (over 300C) stomata close to conserve water. As a result, the amount of CO2 in the leaves decreases. Meanwhile, ribulose 1,5 bisphosphate reacts with O2 instead of CO2 to produce glycolate with 2-carbons. So this cycle is called glycolic acid cycle or C2 cycle. This cyclic pathway is also called the photosynthetic carbon oxidative (PCO) cycle. Glycolate enters the cell’s peroxisomes and reacts with oxygen to produce certain products. These substances enter the mitochondria and react to produce CO2. However, photorespiration does not occur because there is sufficient CO2 in the bundle sheath cells. Photorespiration can reduce the photosynthetic rate of C3 plants by up to 25%. Two amino acids glycine and serine are produced in this process. According to scientists Kazaki and Takeba (1996), photorespiration protects plants from damage to photosynthesis caused by photosynthesis at high light intensity, temperature and oxygen concentration. Sometimes photorespiration is called peroxisomal respiration.

1. Food production: Green plants produce carbohydrates in the process of photosynthesis. The food produced in the C3 cycle is glucose and the food produced in the C4 cycle is pyruvic acid.
2. Animal food: Food produced in the process of photosynthesis is stored in the plant body. Animals use plants as food
accepts
3. Energy Conversion: In this process solar energy is converted into chemical energy. Photosynthesis is the process of energy conversion on Earth.
4. Animal Respiration: Carbohydrates produced in the process of photosynthesis are used as respiratory substances.
5. Prevention of environmental pollution: In the process of photosynthesis, CO2 is taken in and O2 is released. As a result, the balance of O2 and CO2 is preserved and pollution of the environment is prevented.
6. Temperature conservation: Plants absorb solar energy during photosynthesis. It holds the temperature of the earth. As a result, the ambient temperature is tolerable.
7. Physiological growth of plants: Plants produce food through the process of photosynthesis. This food promotes physical growth of plants. So photosynthesis plays a role in the physical growth of plants.
8. Development of Human Civilization: Contribution of photosynthesis to human civilization’s essential food, materials, medicine, fuel, furniture, paper etc.
9. Producers: Green plants are producers. They produce food through the process of photosynthesis. Biodiversity is dependent on producers.
10. Medicine: Many drugs including morphine, quinine, reserpine, belladonna used in medicine are available from plants. These drugs are the result of photosynthesis.

1. Number of leaves: If the number of leaves in the plant body is more, the amount of photosynthesis is more and if the number of leaves is less, the amount of photosynthesis is less.
2. Age of leaves: More photosynthesis occurs in middle aged leaves. Photosynthesis is low in young and old leaves.
3. Leaf structure: The rate of photosynthesis depends on the nature of the leaf, the arrangement of mesophyll cells and the number of stomata.
4. Protoplasm: A leaf with more protoplasm has a higher rate of photosynthesis.
5. Chlorophyll: If the amount of chlorophyll is high in the leaves, the amount of photosynthesis is high.
6. Sugar content: If sugar is high in the leaves, the rate of photosynthesis is low.
7. Potassium: If the amount of potassium in the leaves is low, the photosynthesis will decrease.
8. Enzymes: The amount of enzymes required controls the rate of photosynthesis.

Magnesium and iron form chlorophyll. When these minerals are lacking, the production of chlorophyll decreases and the rate of photosynthesis also decreases.

A particular effector of photosynthesis is temperature. The optimum temperature for photosynthesis is 22-350C. At temperatures above 450C, photosynthesis in most plants ceases. For every 100C increase in temperature, the rate of photosynthesis increases about 2.2-2.6 times. Some bacteria and high-temperature blue-green algae can carry out photosynthesis at temperatures up to 700C.