Several factors can affect the rate of photosynthesis:
- light intensity
- carbon dioxide concentration
- temperature
What decreases the rate of photosynthesis?
Several factors can affect the rate of photosynthesis:
- light intensity.
- carbon dioxide concentration.
- temperature. In which Colour photosynthesis is fastest? Blue and red light are most effective for photosynthesis. This is because chlorophyll pigments s absorbs maximum in blue and red regions. ...
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 are the three things needed for photosynthesis?
What are the three things needed for photosynthesis?
- Light intensity. Without light, plants cannot photosynthesize, even if there is enough water and carbon dioxide in the environment.
- Carbon dioxide concentration. Carbon dioxide is a necessary reagent for the process to occur.
- Amount of chlorophyll. ...
- Water. ...
- Temperature. ...
- Minerals and nutrients. ...
What would happen to oxygen in photosynthesis increased?
photosynthesis is driven by higher oxygen consumption. Gases in photosynthesis are made from oxygen. The rate of photosynthesis must be higher in order to produce more oxygen. photosynthesis in light, causing rapid rises in oxygen levels, as it is warmer.
What are 3 factors that increase or decrease the rate of photosynthesis?
The main factors affecting rate of photosynthesis are light intensity, carbon dioxide concentration and temperature.
Would decrease the rate of photosynthesis in a plant?
Temperature The higher the temperature then typically the greater the rate of photosynthesis, photosynthesis is a chemical reaction and the rate of most chemical reactions increases with temperature. However, for photosynthesis at temperatures above 40°C the rate slows down.
What are the 4 factors that affect photosynthesis?
Photosynthesis is affected by light, temperature, water, and CO2. Stomata affect the process of transpiration and do not affect photosynthesis.
What are the 5 factors that affect photosynthesis?
10 Major Factors Affecting PhotosynthesisThe following points highlight the ten major factors affecting photosynthesis. The factors are: 1. Light 2. ... Light Intensity:Photo-Oxidation:Light Quality:Duration of Light Period:Carbon Dioxide Supply:Absorption of Carbon Dioxide:Carbon Dioxide Concentration:More items...
What increases the rate of photosynthesis?
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.
Can respiration reduce the rate of photosynthesis?
This means the rate of photosynthesis increases beyond the rate of respiration (point D). Now more carbon dioxide is being taken in by the plant for photosynthesis than is produced by the plant during respiration. So the carbon dioxide uptake increases.
Can transpiration reduce the rate of photosynthesis?
Excess water loss (transpiration) causes stomata closure and therefore decreases the photosynthetic rate. Transpiration from the leaves is made mainly through the stomata and partly through the cuticle.
Why is there a decrease in the rate of photosynthesis at high light intensity?
As the intensity of light increases, the process of photosynthesis increases. But after reaching a certain extent though light intensity increases photosynthesis cannot increase more. At very high light intensity chlorophyll may get damaged and the rate may fall down steeply.
How does photosynthesis affect dry matter production?
Photosynthetic CO 2 assimilation per unit area and time, i.e. rate ( A ), is inhibited by rapidly developing WD in physiological studies, so it is assumed to be responsible for decreased dry matter production. However, leaf area is also very important for total production. This applies in the field, where slowly developing WD results in a small leaf area index, which often dominates production with only small effects on A ( Legg et al., 1979; Sinclair and Purcell, 2005 ). However, the perceived need to apply understanding of photosynthesis to alleviation of practical problems such as loss of crop yield due to WD has increased interest in ‘water stress physiology’. Many basic questions remain about how cellular processes are regulated by WD. As A dominates cell metabolism, with very large fluxes of carbon, nitrogen and energy ( Lawlor, 2001 ), it is potentially vulnerable to WD ( Kramer and Boyer, 1995 ). It is integrated with respiration and aspects of electron transport (ET) and ATP synthesis in the mitochondria ( Atkin and Macherel, 2009 ), and changes in A and energy are related, in ways still unclear, to accumulation of ‘stress metabolites’ (e.g. proline), gene expression and protein synthesis. It is now appreciated ( Herbert, 2002; Scheibe et al., 2005; Rumeau et al., 2007) how tightly integrated photosynthetic metabolism is, and how difficult it will be, without understanding of the system and a clear model, to engineer plants for large biomass and yield production under WD ( Sinclair and Purcell, 2005; Bohnert et al., 2006 ). It is also extremely doubtful if one model of photosynthesis and metabolism will suit all plant × environment combinations ( Reynolds et al., 2005 ). Differences between plants grown in controlled environments and those in the field must be considered, especially when considering the potential for genetic modification ( Sinclair and Purcell, 2005 ). Quantitative assessment of conditions in photosynthetic cells under WD is essential if the current flood of information from genomics, proteomics and metabolomics is to be used to improve plant production under WD ( Flexas et al., 2004 b; Chaves et al., 2009 ). First, general agreement on the qualitative processes involved is required, from which quantitative species × environment models may emerge.
What is the metabolic potential for photosynthesis?
metabolic potential for photosynthesis ( Apot ), which is determined by the capacity of the system related to the amounts and activities of components of light-harvesting, electron transport and energy-transduction processes, and of carbon metabolism, including enzymes (e.g. Rubisco) and processes (RuBP synthesis), of the Calvin cycle.
How is control of A and Apot distributed?
Control of A and Apot is distributed between many metabolic components and processes that vary in importance as conditions – environmental and within the plant – change ( von Caemmerer, 2000 ). Probably control varies, depending on the plant and on environmental conditions during growth and under water deficit.
What conditions do plants grow in?
Plants are grown under glasshouse or controlled-environment conditions, often at low light, and samples of leaf are taken and subjected to WD under no or low light, resulting in rapid stress ( Kaiser and Heber, 1981; Dietz and Heber, 1983; Kaiser 1984, 1987; Renou et al., 1990; Tourneux and Peltier, 1995 ).
Why are chloroplasts more sensitive to WD than mitochondria?
Chloroplasts are much more sensitive to WD than mitochondria because when A stops RL is maintained ( Lawlor and Fock, 1975 ), although ROS is formed in both organelles, and Bartoli et al. (2004) consider mitochondria to be sensitive to ROS. Regulatory systems for dealing with excess e− are different in the two organelles: multiple regulatory pathways in mitochondria may provide greater protection. Perhaps the range of energy states is smaller in mitochondria than in chloroplasts, which experience large and rapidly changing radiant energy fluxes. Chloroplasts (particularly those not adjusted to strong light, WD, etc) may have inadequate mechanisms to prevent the accumulation of H + and to dissipate the H + gradient if it is large, except through ATP synthase. ATP synthases from both organelles, which have a different evolutionary origins and structure in plants ( Hamasur and Glaser, 1992 ), may also differ in susceptibility to their environment, e.g. ROS and ion concentrations. How conditions in the organelles affect use of reductant and generation of ATP is not known: these topics deserve more attention in the context of WD.
Which species of ROS affect other subunits of ATP synthase?
Different species of ROS affect other subunits of ATP synthase, e.g. H 2 O 2 impairs the α- and β-subunits, but more slowly than 1 O 2 damages the γ-subunit.
Does water deficit affect photosynthetic rate?
Water deficit (WD) decreases photosynthetic rate ( A) via decreased stomatal conductance to CO 2 ( gs) and photosynthetic metabolic potential ( Apot ). The relative importance of gs and Apot, and how they are affected by WD, are reviewed with respect to light intensity and to experimental approaches.
How do ectomycorrhizal symbioses affect the C balance of a plant?
Ectomycorrhizal symbioses can influence the C balance of the plant via a number of normally interrelated processes, including net photosynthetic rate and mineral nutrition. However, there is an increasing awareness of the importance of sink strength in determining the rates of assimilation of C in the leaves (Herold, 1980; Gifford and Evans, 1981; Sonnewald et al., 1994). Consequently, mycorrhizal fungi may, through their ability to maintain a net flux of C in their favour ( Lewis and Harley, 1965a ), and to increase the overall C demand of the root, exert direct non-nutritional impacts upon C assimilation by the plant. Several studies have shown that photosynthetic rates are enhanced in ectomycorrhizal plants relative to those grown in the non-mycorrhizal condition ( Reid et al., 1983; Nylund and Wallander, 1989) but the confounding influence of enhanced mineral nutrient concentration in the foliage of colonized plants has made it difficult to determine the relative importance of nutritional and non-nutritional effects. In order to discriminate between nutritional and sink effects, Rousseau and Reid (1990) grew seedlings of Pinus taeda in the mycorrhizal and non-mycorrhizal condition, but provided the uncolonized plants with various additional amounts of P so that tissue P concentrations were the same as those of plants colonized by Pisolithus tinctorius. The photosynthetic rates of the mycorrhizal plants, some of which were lightly, some moderately and some heavily colonized by the fungus, were then compared with those of uncolonized plants from each of the P treatments, before harvests were taken to determine tissue P status.
How does ECM affect the C balance of a plant?
Formation of ECM symbioses can influence the C balance of the plant via a number of interrelated processes but, in particular, through its effects on net photosynthetic rate and mineral nutrition. These influences can be detected both in the leaves which are the C sources and in the roots and their symbionts which are the C sinks. The impacts of ECM colonization can be detected in the source leaves. The regulation of sucrose synthesis in the leaf cytosol mainly occurs through the activities of sucrose phosphate synthase (SPS) and fructose 2,6-bisphosphatase (FBPase), the latter being inhibited by an effector metabolite, fructose 2,6-bisphosphate (F26BP) (Quick and Schaffer, 1996 ). Loewe et al. (2000) reported increased activation of SPS and decreased levels of the inhibitor FBPase in ECM seedlings of spruce ( Picea abie s). This is indicative of an increased capacity for sucrose synthesis in source tissues of ECM plants. This effect of ECM formation is almost certainly linked to the role of the fungal partners as sinks for assimilates produced in the source tissues. The importance of sink strength in determining the rates of C assimilation in leaves is now well established ( Herold, 1980; Gifford and Evans, 1981; Sonnewald et al., 1994; Quick and Shaffer, 1996). In the context of mycorrhizas, the assumption is that, through their ability to maintain a net flux of C in their favour ( Lewis and Harley, 1965a; Nehls et al., 2001) and to increase the overall C demand of the root ( Finlay and Söderström, 1992 ), the fungal partners exert direct impacts upon C assimilation by the plant. It remains necessary to determine the relative importance of enhanced provision of nutrients by the ECM fungi and the increased sink strength arising from their presence in determining the observed shifts of plant carbon balance.
How does micropropagation work?
Micropropagation is a method to produce genetically identical plantlets by using tissue culture techniques. Recent research revealed that chlorophyllous plantlets in vitro had high photosynthetic ability but that their net photosynthetic rates were restricted by the in-vitro environmental conditions, mainly the low CO2 concentration during photoperiod. Photoautotrophic micropropagation refers to micropropagation with no exogenous organic components (sugar, vitamins, etc.) added to the medium, and it has been developed along with the development of techniques of in-vitro environmental control. CO 2 concentration, photosynthetic photon flux, relative humidity, and air current speed in the vessel are some of the most important environmental factors affecting plantlet growth and development; controlling these factors requires knowledge and techniques of greenhouse and horticultural engineering as well as the knowledge of physiology of in-vitro plantlets. Photoautotrophic micropropagation has many advantages with respect to improvement of plantlet physiology (biological aspect) and operation/management in the production process (engineering aspect), and it results in reduction of production costs and improvement in quality of plantlets. Feasibility of photoautotrophic micropropagation has been reportedly shown in both herbaceous and woody plant species. Photoautotrophic micropropagation will give a breakthrough in large-scale production of genetically identical, pathogen-free plantlets with vigorous growth and better overall quality and therefore, has a great potential to be introduced in transplant production and biotechnology research.
Does CO2 affect photosynthesis?
Indeed, owing to the elevated ambient CO2 concentration, the internal leaf concentration remains fairly high with limited effects on photosynthesis, whereas this partial closure can have important negative effects on photosynthesis at normal ambient levels ( Van der Mescht et al., 1999 ). In addition, stomatal closure also has beneficial effects as the plants evaporate less water. As a consequence, it could be expected that dry soil conditions and/or high VPDs would be much more harmful for potato crops growing at ambient than at elevated CO 2. Apart from an overall decreased yield, the relative CO 2 effect will be much more important for water-stressed than for well-watered crops because of the better WUE. In the CHIP project, the option was taken to provide the plants with ample water to avoid drought stress. This may be the most important reason for the lack of CO 2 response in some experiments as reported by Craigon et al. (2002). As summarized in Table 19.1, yield increase due to elevated CO 2 exposure was high in Italy and rather low in Belgium, Sweden, Germany and Finland. Irrigation is important in dry conditions, but a high leaf to air water vapour pressure difference may continue to be a major limitation to CO 2 uptake even at twice the current concentration ( Bunce, 2003 ). This is probably one of the reasons for a generally lower yield in Italy compared to the other sites, even at ambient levels of CO 2, but the relative yield increase at elevated CO 2 is higher. Indeed, in spite of ample water supply, the VPD remains high in Italy ( Table 19.1 ). In temperate climate regions, the beneficial effect of ample water supply on stomatal opening is more important, and photosynthesis is less reduced compared to elevated CO 2. However, other stresses than drought might be involved, and moreover, if comparisons are made with other experiments than CHIP, the response to CO 2 increases appears to be highly cultivar dependent ( Schapendonk et al., 2000) and largely variable from year to year.
Why is the rate of photosynthesis limited?
Thus, the plant reaches a "light saturation point" and the rate of photosynthesis is limited due to a limited amount of carbon dioxide, or due to some other limiting factor.
How does light affect photosynthesis?
The light's photons excite the electrons in the pigments of the photosystems which activates the light reactions portion of photosynthesis. The more light there is, the more photosystems in the thylakoid membrane can be activated. However, light intensity can only increase up to a certain point before the rate of photosynthesis no longer increases.
What happens to the ATP and NADPH in photosynthesis?
Once there is a sufficient intensity of light, the ATP and NADPH that come from the light reactions will be in abundance. For the remaining part of photosynthesis to occur (the Calvin cycle), carbon dioxide is needed. Even if more and more ATP and NADPH are being formed, they will not be able to act if more carbon dioxide isn't entering the plant.
Is photosynthesis dependent on temperature?
It also shows that the rate at which photosynthesis levels out is dependent upon other factors—both plants in 0.1% CO₂, they cannot photosynthesize at nearly the rate of the plants in 0.4% CO₂. Similarly, plants photosynthesize at a greater rate in higher temperatures (generally—not in temperatures that are too hot—this is also dependent ...
What Are The Internal Factors Affecting photosynthesis?
- Let us look at some of the internal factors affecting photosynthesis: 1. The internal or plant factors greatly depend on the genetic predisposition and basically on the growth of the plant. 2. These factors include the number, size, age, and orientation of leaves. It also includes chlorophyll content, accumulation of byproducts, and hormones. (i) Chlorophyll Content of Leaves: The chlo…
Blackman’s Law of Limiting Factors
- For studying the external factors affecting the rate of photosynthesis, it is essential to have a knowledge of Blackman’s Law of Limiting Factors.
- Before \(1905,\) early scientists attempted to determine the effect of individual factors on the photosynthetic rate in terms of minimum, optimum and maximum values which are known as cardinal points.
- For studying the external factors affecting the rate of photosynthesis, it is essential to have a knowledge of Blackman’s Law of Limiting Factors.
- Before \(1905,\) early scientists attempted to determine the effect of individual factors on the photosynthetic rate in terms of minimum, optimum and maximum values which are known as cardinal points.
- The simultaneous effects of other factors also have an importance in determining the rate of photosynthesis.
What Are The External Factors Affecting photosynthesis?
- Let us explain the external factors affecting photosynthesis: 1. The external factors affecting photosynthesis include environmental factors like availability of sunlight, temperature, the concentration of carbon dioxide and water. 2. Factors available at suboptimal levels help in determining the rate of photosynthesis at any point. 3. Some of the ...
Summary About Factors Affecting Photosynthesis
- The process through which plants transform solar energy into chemical energy in the form of food is known as photosynthesis. Photosynthesis is the optimal mechanism for a living entity that lacks the capacity to actively move around in search of food. Photosynthesis is equally crucial for the food web’s consumers, and it serves as the beginning point for all ecological food chains. A…
Frequently Asked Questions (FAQs) on Factors Affecting Photosynthesis
- Let us look at some of the frequently asked questions on internal and external factors affecting photosynthesis: Q.1. Name the factors affecting photosynthesis. Ans:The top five factors affecting the rate of photosynthesis are chlorophyll content of leaves, the internal structure of leaves, light intensity, carbon dioxide concentration, and temperature. Q.2. What do you mean b…