The Effects of Concentration of CO2 on Photosynthesis

Deadline is approaching?

Wait no more. Let us write you an essay from scratch

Receive Paper In 3 Hours

Corn plant life and sunflowers are plants that grow in areas that ride sufficient nutrient and water supply. Such environments provide variable prerequisites in ambient concentration of CO2 that is necessary for transpiration and breathing processes. Photosynthesis is the process through which flowers utilize the sunlight rays to assist in synthesizing CO2 and water in producing energy and oxygen. This process is very necessary in both the plant’s life and the animal lifestyles. It produces the oxygen required by animals while permitting the plants to eliminate the CO2 fuel from the environment. As a factor in the process of photosynthesis, the attention of CO2 has an important role in the process. Notably, it varies across the plants in both the terrestrial plants. This experiment sought to investigate the effects of the concentration of CO2 on the photosynthesis process using sunflower and corn plants as the major crops growing in the field. Predominantly, most scientific researchers established that the rate of photosynthesis in most of the C3 plants increases with increase in the concentration in the concentration of CO2. Therefore, the experiment was carried out under ambient conditions of room temperature and pressure within the biology laboratory. Two variables are important in this experiment: the concentration of CO2 and the gaseous exchange rate in the plant leaves (Schmid, 81-95)

The processes of photosynthesis, respiration, and the transpiration elements help the plants to develop and grow in the environment. Photosynthesis takes place in the green pigments of the plants. This explains why the experiment focused on the leaves of the two plants in the ecosystem. Thus, any factor that affects the normal function of the leaf will affect the rate of photosynthesis and consequently the rate of growth and development within the plant organs in the environments. Several experimental reports have indicated differences among various plant species regarding the rate of photosynthesis, irradiance and the baseline reactions to a variation of the conditions in the environment (Busch & Florian, 200-212).

Materials and Methods


C4- corn plants (Zea maize) leaf

C3- sunflower (Helianthus annulus) leaf

500 ml of water

Qubit/ Vernie system


Leaf chamber

Plastic syringes

Drier et solution

Vaseline gel

LED output system


Three conditions were set up in the laboratory to help in the investigation of the variations in the concentrations of CO2 and its effects on the rate of photosynthesis in the laboratory. These included three conditions of CO2 variation. First, there was a low concentration of CO2 setup. Secondly, a high concentration of CO2 was also established in the laboratory. Finally, an ambient concentration condition was established in the setup. After that, a bypass was established for all the conditions in the laboratory. The bypass was to help attain a stable baseline for both plant leaves in the setups. The Vaseline gel was then smeared on both leaves and the leaves placed in their respective chambers in the laboratory. The leaves were the allowed to stay in the chamber for a few minutes until the level of CO2 concentration became stable in both cases in the settings. The variation in the concentrations of CO2 was then measured and recorded in the files as shown in the Excel files of the experiment. The experimental setup was then monitored for the duration of time and the findings recorded as documented in the class reports.


The difference in the concentration of CO2 was derived at by subtracting the final concentrations from the initial one in the laboratory manuals. The results are enumerated in the excel folders. There was a significant variation in the level of variation witnessed in this study. The ambient conditions for experiment represented the normal field growth provisions for the process of photosynthesis in the plants. The results showed that C3 experienced a higher rate of photosynthesis with the increase in the concentration of the CO2 in the experiment. There was an improved response to the higher concentration of CO2 as opposed to the ambient air conditions during the experiment. At irradiance above 1000, the average rate of flow becomes higher than when it is lower than 1000 on average during the experiment. The average in this case, for instance, is averagely 1024 when above 1000 while the other case involves a case. The temperature levels slightly change with the rising level of the sun in the universe.

However, at the ambient baseline conditions, C3 has a higher rate of metabolic processes as compared to the C4 under study. Prominently, at the baseline of 195, the irradiance for C3 was 800.84 while that of C4 was 800. However, C3 recorded lower rates as compared to C4 under the same conditions in the environment. Moreover, with increased concentrations in the ambient levels, the rate of photosynthesis increases progressively with the change in flow rates in the chamber.


The experiment illustrates that the rate of photosynthesis is normally affected by both the respiratory and transpiration elements in the environment. The ambient concentration of the CO2 acted as the case control for the study setup in establishing the concentration of the CO2 and its effect in the process of photosynthesis in the laboratory setting. The Vaseline was applied to reduce the rate of water loss and avoid shrinking in the plant leaves (Kramer, 29-33). The difference in the variations of the rate of leaf response and the natural environmental setup help to explain the natural organization of the stomata cells. The organization of the stomata cells of the sunflower enables the leaf to respond faster than the corn leaf in the experimental study. This implies that various species display different rates of photosynthetic rates and other metabolic activities in the ecosystem (Kill, 34).

Naturally, the increase in CO2 concentration triggers a number of activities in the plant’s life. It initiates the metabolic activity of the stomata cells that boost the rate of cellular mechanism within the plant cells. Such irradiance differences in photosynthetic component illustrate the dynamisms of the role of the environment in the rate of metabolic activities in photosynthesis (Lawlor, & Mitchell). Typically, photosynthesis takes place at the initiation of the basic elements of the environment. Such include sunlight, water, and CO2. From the experiment, it is evident that the rate of photosynthesis directly depends on both the internal environmental conditions as well as the internal structure of the leaf. Importantly, the rate of gaseous exchange and water loss also influence the rate of photosynthesis in all leaves in the environment (Vanaja, 84).


Therefore, the level of concentration of CO2 affects the rate of photosynthesis in the plant leaves. Notably, the study showed that the higher the irradiance, the higher the rate of photosynthesis in the environment (Morison, James, & Gifford, 789-796). Thus, the rate of energy absorption and development also depends on the level of metabolic mechanisms within the environment. From this study, it is evident that the rate of photosynthesis varies among plant species in the living environments. C4 plants respond faster to the increase in concentrations compared to the C3 plants within similar environmental conditions. The experiment demonstrates the differences in the structure of the stomata openings as well as the concentration of the green matter of the plant- chlorophyll. Notably, the plant leaves play a great role in the growth and development of other organs. Thus, this experiment is crucial in explaining the relationship between the concentration of CO2 and the rate of photosynthesis between two species of plants in a similar environment.

Work cited

Busch, Florian A., et al. “C3 plants enhance rates of photosynthesis by reassimilating photorespired and respired CO2.” Plant, Cell & Environment 36.1 (2013): 200-212.

Vanaja, M., et al. “Increasing Atmospheric Carbon Dioxide and Temperature—Threats and Opportunities for Rainfed Agriculture.” Agriculture under Climate Change: Threats, Strategies and Policies 1 (2017): 84.

Killi, Dilek, et al. “Adaptation to high temperature mitigates the impact of water deficit during combined heat and drought stress in C3 sunflower and C4 maize varieties with contrasting drought tolerance.” Physiologia Plantarum (2016).

Schmid, I., et al. “Effects of CO2 Enrichment and Drought on Photosynthesis, Growth and Yield of an Old and a Modern Barley Cultivar.” Journal of Agronomy and Crop Science 202.2 (2016): 81-95.

Sadras, Victor O., Francisco J. Villalobos, and Elias Fereres. “Radiation Interception, Radiation Use Efficiency and Crop Productivity.” Principles of Agronomy for Sustainable Agriculture. Springer International Publishing, 2016. 169-188

Morison, James IL, and Roger M. Gifford. “Stomatal sensitivity to carbon dioxide and humidity a comparison of two C3 and two C4 grass species.” Plant Physiology 71.4 (2013): 789-796.

Kramer, Paul J. “Carbon dioxide concentration, photosynthesis, and dry matter production.” BioScience 31.1 (2011): 29-33.

Lawlor, D. W., and R. A. C. Mitchell. “The effects of increasing CO2 on crop photosynthesis and productivity: a review of field studies.” Plant, Cell & Environment 14.8 (1991): 807-818.

This sample could have been used by your fellow student... Get your own unique essay on any topic and submit it by the deadline.

Let a professional writer get your back and save some time!

Hire Writer

Find Out the Cost of Your Paper

Get Price