Goal 2 - Photosynthesis
Photosynthesis
Photosynthesis is the way a plant makes food for itself.
Oxygen is released as a by-product of photosynthesis.
Plants "breathe in" carbon dioxide and "breathe out" oxygen.
The tree draws up water through its roots and the water is then drawn up through the tree and comes out through the stomata in its leaves.
Photosynthesis (a bit harder)
Sunlight is absorbed into the leaf by a green pigment called chlorophyll, which absorbs red and blue light, but reflects green light, causing the leaves to appear green.
This light energy from the SUN is then converted into a chemical energy in the form of starch or sugar (glucose):
This equation translates as six molecules of water (6H2O) plus six molecules of carbon dioxide (6CO2) produce one molecule of sugar (C6H12O6) plus (O2). Oxygen is a waste product for the plant.
Photosynthesis is the way a plant makes food for itself.
- It is in the leaves that most photosynthesis takes place.
- Photosynthesis is the process by which the plant is able to use light (“photo”) energy to make (“synthesis”) food in the form of carbohydrates (glucose).
- Chlorophyll in the "green" part of the leaves captures energy from the sun and this powers the building of food from very simple ingredients - carbon dioxide and water.
Oxygen is released as a by-product of photosynthesis.
Plants "breathe in" carbon dioxide and "breathe out" oxygen.
- They breathe through tiny holes in their leaves called stomata; they also lose water through the stomata.
The tree draws up water through its roots and the water is then drawn up through the tree and comes out through the stomata in its leaves.
- The whole process of sucking up water and losing it again is called transpiration.
Photosynthesis (a bit harder)
Sunlight is absorbed into the leaf by a green pigment called chlorophyll, which absorbs red and blue light, but reflects green light, causing the leaves to appear green.
- Chlorophyll is not a very stable compound and plants continuously have to make or synthesize more.
- Chlorophyll is located in the chloroplasts.
- Chloroplasts are the organelle where photosynthesis takes places.
- Chloroplasts are made up of several layers of short membranes called grana
- It is in the grana where photosynthesis takes place.
This light energy from the SUN is then converted into a chemical energy in the form of starch or sugar (glucose):
- 6H2O + 6CO2 makes C6H12O6 + 6O2
- water + carbon dioxide makes glucose + oxygen
- reactants are on the left of the equation and products are on the right side of the equation
This equation translates as six molecules of water (6H2O) plus six molecules of carbon dioxide (6CO2) produce one molecule of sugar (C6H12O6) plus (O2). Oxygen is a waste product for the plant.
Transpiration
Transpiration (a bit harder)
Water (H2O) that contains valuable nutrients and minerals is sucked out of the soil by the plants roots and passed up through the leaves where they mix with carbon dioxide (CO2) from the air and are converted into sugars that are absorbed by the plant to make it grow.
The fact that plants take in carbon dioxide is thought to be important in the fight against global warming since the overproduction of carbon dioxide from the burning of fossil fuels by human beings could be a major factor.
Water (H2O) that contains valuable nutrients and minerals is sucked out of the soil by the plants roots and passed up through the leaves where they mix with carbon dioxide (CO2) from the air and are converted into sugars that are absorbed by the plant to make it grow.
- During this process the plant releases oxygen (O2) into the air, and this is why we need to plant as many trees as we can to enable us to have enough oxygen to breathe.
The fact that plants take in carbon dioxide is thought to be important in the fight against global warming since the overproduction of carbon dioxide from the burning of fossil fuels by human beings could be a major factor.
Lets Sum It up
- Light hits the leaves of the plant
- Chloroplasts with chlorophyll split the water
- Carbon dioxide enters the leaf through holes called the stomata. Joins with energy n the chloroplasts and makes sugar (glucose).
- Sugar (glucose) can do any of the following in the plant
- goes into tubes to roots, stems, fruit, seeds for storage
- used to make plant tissues or cellulose
- used for energy by the plant
- some stored as starch
- Sugar (glucose) is eaten by animals
- Oxygen is released into the air