How do I calculate the rate of photosynthesis?
Variables
- Independent variable - the light intensity (how close the light is).
- Dependant variable - the number of oxygen bubbles given off (the rate of photosynthesis).
- Controlled variables - the size of the pondweed, the volume of water used and its temperature.
What can be used to measure the rate of photosynthesis?
- Set up the apparatus as in the diagram.
- Leave for five minutes for the pondweed to acclimatise to the new light intensity.
- Count the number of bubbles given off in one minute.
- Move the light 10 cm further back.
- Leave for five minutes for the pondweed to acclimatise again.
What things affect the rate of photosynthesis?
The three main things affecting the rate of photosynthesis are: Light Temperature Carbon dioxide These three factors are called LIMITING FACTORS. In a process like photosynthesis which is affected by more than one factor, its rate is limited by the factor which is closest to its minimum value.
What are the three stages in photosynthesis?
what are the 3 stages of photosynthesis. The three events that occur during the process of photosynthesis are: (i) Absorption of light energy by chlorophyll. (ii) Conversion of light energy to chemical energy and splitting of water molecules into hydrogen and oxygen. (iii) Reduction of carbon dioxide to carbohydrates.
What is a rate of photosynthesis?
The rate of photosynthesis is a gross measure of the rate at which a plant captures radiant energy and fixes it in organic carbon compounds. However, it is often more important to consider, and very much easier to measure, the net gain.
Why is the rate photosynthesis?
The main factors affecting rate of photosynthesis are light intensity, carbon dioxide concentration and temperature.
What does a higher rate of photosynthesis mean?
So in the case of a plant, a higher light intensity means more packets of light called “photons” are hitting the leaves. As you rise from low light intensity to higher light intensity, the rate of photosynthesis will increase because there is more light available to drive the reactions of photosynthesis.
What is the rate of photosynthesis controlled by?
The chemical reactions involved in photosynthesis are controlled by enzymes . As with any other enzyme-controlled reaction, the rate of photosynthesis is affected by temperature. At low temperatures, the rate of photosynthesis is limited by the number of collisions between enzymes and substrate.
What controls the rate of photosynthesis in a plant?
Three factors can limit the rate of photosynthesis: light intensity, carbon dioxide concentration and temperature.
How does the rate of photosynthesis affect plant growth?
A higher rate of photosynthesis not only causes the leaves to grow larger, but could also cause longer and thicker roots, or more abundant flowering.
What is the highest rate of photosynthesis?
Light between 400-700 nm wavelength constitute the photosynthetically active radiation (PAR). Maximum absorption of light by chlorophyll a occurs in red and blue regions of the absorption spectrum. So that, the rate of photosynthesis is maximum in red and blue light of the visible spectrum.
How can you increase the rate of photosynthesis?
Several strategies for improving photosynthesis have recently been proposed, such as reducing light-harvesting antenna size, introducing components of algal CO2-concentrating mechanisms, engineering of photorespiratory bypasses, and accelerating recovery from photoprotection (NPQ).
Why does rate of photosynthesis plateau?
At higher carbon dioxide concentrations (plateau of graph), further increasing the carbon dioxide concentration does not increase the rate of photosynthesis meaning another factor is limiting photosynthesis.
Why can we measure the rate of photosynthesis by measuring the volume of oxygen?
By actually measuring the volume of oxygen gas produced by a plant, you can work out the rate at which photosynthesis is happening. The more oxygen given off, the higher (or faster) the rate of photosynthesis.
How can the rate of photosynthesis be increased?
Light intensity Without enough light, a plant cannot photosynthesise very quickly - even if there is plenty of water and carbon dioxide and a suitable temperature. Increasing the light intensity increases the rate of photosynthesis, until some other factor - a limiting factor - becomes in short supply.
How can the rate of photosynthesis be measured using products or reactants?
Using an IRGA – Uptake of CO2 can be measured with the means of an IRGA (Infra-Red Gas Analyser) which can compare the CO2 concentration in gas passing into a chamber surrounding a leaf/plant and the CO2 leaving the chamber.
What is the process of photosynthesis?
Most life on Earth depends on photosynthesis .The process is carried out by plants, algae, and some types of bacteria, which capture energy from sunlight to produce oxygen (O 2) and chemical energy stored in glucose (a sugar).
What is the chemical used in photosynthesis?
ATP. Noun. (adenosine triphosphate) chemical found in most living cells and used for energy. C3 photosynthesis. Noun. Used by the majority of plants, it involves producing a three-carbon compound called 3-phosphoglyceric acid during the Calvin Cycle, which goes on to become a sugar called glucose. C4 photosynthesis.
How does carbon dioxide change water into glucose?
Within the plant cell, the water is oxidized, meaning it loses electrons, while the carbon dioxide is reduced, meaning it gains electrons. This transforms the water into oxygen and the carbon dioxide into glucose. The plant then releases the oxygen back into the air, and stores energy within the glucose molecules.
What is the Calvin cycle?
Involves producing a four-carbon intermediate compound, which splits into carbon dioxide and a three-carbon compound during the Calvin Cycle in plants that do not get a lot of light or water. Calvin cycle. Noun.
What is the energy that plants use?
Inside the plant cell are small organelles called chloroplasts, which store the energy of sunlight. Within the thylakoid membranes of the chloroplast is a light-absorbing pigment called chlorophyll, which is responsible for giving the plant its green color. During photosynthesis, chlorophyll absorbs energy from blue- and red-light waves, and reflects green-light waves, making the plant appear green.
Where does the light dependent reaction take place?
The light-dependent reaction takes place within the thylakoid membrane and requires a steady stream of sunlight, hence the name light- dependent reaction. The chlorophyll absorbs energy from the light waves, which is converted into chemical energy in the form of the molecules ATP and NADPH.
Which pigment is essential for photosynthesis?
plants' green pigment that is essential to photosynthesis.
Why is photosynthesis faster than respiration?
The rate of photosynthesis is always faster than of respiration because more substrate needs to be present during respiration. Rate of photosynthesis. Photosynthesis is the process in which carbon di oxide gas and water and light energy are reactants and oxygen , carbohydrate (glucose) and energy stored in it are products .
How to determine rate of a process?
To know rate of the process one can use either product formed or reactant used with respect to time and space ( surface area of leaf or weight of green tissue).Rate of PS. can be :::::1. Volume of oxygen evolved per minute (hour )per unit area of leaf (per gram of organ). 2 Amount of glucose-carbohydrate- formed ( increase in weight) per unit time (minute or hour or day)per unit area of leaf (or per gram of tissue). 3 Volume of carbon di oxide gas used per unit leaf area (per gram of organ)per unit time (minute or hour). etc. etc.
Objective
Student compares the rates of photosynthesis for various light sources.
Experimental Procedure
Create your hypothesis as to which type of light will be best for photosynthesis and why. Prepare for the experiment by creating an infiltration solution. Combine 1 L of water with ½ teaspoon of baking soda and 3-4 drops of liquid soap. Next, punch leaf disks from healthy green spinach leaves.
What is the rate of photosynthesis?
The rate of photosynthesis is a gross measure of the rate at which a plant captures radiant energy and fixes it in organic carbon compounds. However, it is often more important to consider, and very much easier to measure, the net gain. Net photosynthesis is the increase (or decrease) in dry matter that results from the difference between gross ...
How much of the nitrogen in a leaf is invested in chloroplasts?
In addition, the photosynthetic capacity of leaves is highly correlated with leaf nitrogen content, both between leaves on a single plant and between the leaves of different species (Woodward, 1994). Around 75% of leaf nitrogen is invested in chloroplasts.
Is net photosynthesis negative in darkness?
Net photosynthesis is negative in darkness, when respiration exceeds photosynthesis, and increases with the intensity of PAR. The compensation point is the intensity of PAR at which the gain from gross photosynthesis exactly balances the respiratory and other losses. The leaves of shade species tend to respire at lower rates than those of sun species. Thus, when both are growing in the shade the net photosynthesis of shade species is greater than that of sun species.
